Modified Brera 3.2 JTS Rebuild. - Alfa Romeo Forum
You are currently unregistered, register for more features.    
 16Likes
Reply
 
Thread Tools
(Post Link) post #1 of 78 Old 03-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling Modified Brera 3.2 JTS Rebuild.

Hopefully, this project will now start to materialize into a fully rebuilt and modified engine. I shall post some pictures as things start to come together. The first batch will be of the sump, the modifications and details of why they were undertaken.

However, below are some major components for re - build:-

https://www.google.co.uk/url?sa=t&rc...lZfgKyQ-J7rI-m

https://www.google.co.uk/search?q=re...xEQsAR6BAgFEAE

https://www.google.co.uk/url?sa=t&rc...223C80qWzsflfp

Autodelta Shop

Further to the above, I managed to find a pair of alloy Cam Covers - ex Camaro V6 I believe. They have a higher profile and naturally; being metal, I hope they will further help to get the heat away from the cylinder heads. Being higher than the close fitting plastic Alfa covers, the extra space underneath will help with scavenging fumes from within the block/engine. The Alfa ones are IMHO very restrictive in this department.
Ken, Speenvark and Matty156 like this.
sizewell is offline  
Sponsored Links
Advertisement
 
Status: -
AO Member
 
Join Date: Jul 2017
County: -
Posts: 468
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
alfaromeo939s is offline  
(Post Link) post #3 of 78 Old 03-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I had my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
The not - too hopefully attached pictures are of a; the 159 standard un - baffled sump., b; the now modified sump with baffles and c; the modified Oil Pick - up snout.

When I took the engine apart, it was pretty obvious the lack of any baffling could contribute to the oil pick - up snout being exposed above the level of oil in the sump, particularly in hard cornering and even possibly in moderate bends, if the engine oil level was not scrupulously maintained at "Full Level". Exacerbating this was the fact that the pick - up itself was fixed at a high level - about 15 mm. + above the sump bottom. It also had a circular mesh pick - up aperture, extending almost to the perimeter of the snout. Such a large area could easily be exposed as the sump tilted and un - baffled oil moved in the direction of the outer radius of any bend.

I purchased a second hand pick up from the States, the snout of which is illustrated in one of the pictures. However, the shape was different, a vertical drop from the pipe coupling, a horizontal section and then another vertical drop to the snout. Better altogether I thought, but it simply would not fit

So the original mesh pick - up face, complete with mesh was ground off, and the new units pick - up face and mesh welded on in it's place. The distance between the bottom of the sump and the face of the pick - up has effectively halved. The level of the oil now has to be considerably lower to expose the pick - up. Well thats the idea anyway.

In conjunction with this, alloy baffles have been welded into the sump so as to channel the oil past the face of the pick - up at all times. The lower sump screen sits above the alloy baffles, which also restricts the potential for oil to flow over the newly welded baffle plates. A small section; which might not be obvious, closes the gap where oil could flow around the oil temp/level sensor posts, on which the sensor is mounted, raising it above the sump floor.

Last edited by sizewell; 03-01-19 at 19:30.
sizewell is offline  
(Post Link) post #4 of 78 Old 03-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
Standard Sump
Attached Images
File Type: jpg Unmodified.jpg (39.9 KB, 59 views)
sizewell is offline  
(Post Link) post #5 of 78 Old 03-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Modified Sump
Attached Images
File Type: jpg Modified.jpg (34.4 KB, 46 views)
sizewell is offline  
(Post Link) post #6 of 78 Old 03-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
New/Modified Pick - up
Attached Images
File Type: jpg New Pick up..jpg (32.8 KB, 28 views)
sizewell is offline  
(Post Link) post #7 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
The next task was to inspect the block and the Oil Drainage Channels back to the sump.

From the picture below, it can be seen there are three drains from the front head, combining into one, which is adjacent the oil feed hole from the sump to the Oil Pump. It is extremely convoluted, almost horizontal at the end nearest the bell housing and capable of holding in excess of 500 ml. This engine, from SAE and MIT papers was designed around a 4 litre capacity with 2.2 litres in the sump and 1.8 litres in transit around the block. It is known to have a very slow rate of spent oil from the mechanicals, to the sump.

A further observation to be made is:- the VVT exhaust ports substantially deposit their discharged oil to the front of the engine, where it almost exclusively drains down past the timing chain system, behind the front cover. The camshaft "Collars" also deposit the lubricating oil from the front camshaft bearing caps into the same region, although, as the oil exhausts the small bearing cap orifice, it is squirted against the camshaft rotating collar and thus spews in the general region around the oil filler cap. Likewise the rear camshafts towards the timing chain end of the head.

The architecture of the head does nothing to promote the return of the spent oil to the sump and substantially what goes down the drainage channels is oil from the hydraulic tappets and the remaining bearing caps. So it is not really a flood - more a low flow, if not a trickle. More on this later (1).

The second picture posted next, shows the single outlet from the front bank, exhausting the block adjacent to the oil feed hole to the pump. It could not under any circumstances be called a "Clean Design", entering the sump, just above a Boss where one of the sump/engine fixing bolts goes.

A further observation is:- "This exhausts the block above the upper Windage Plate - if indeed there was a Windage Plate there, which there is not!!!!!!!". (2) And this point is where Crankshaft Journals and counterweights of cylinders 1 & 2 are rotating!!!!!!!!!! (3)

And when one looks at one of the two drainage channel ports of the rear bank; third picture, it is directly opposite on the other side of the sump, again with "No Windage Plate Screening The Outfall". (4)
Attached Images
File Type: jpg Front Bank Drainage Channel (s).jpg (77.5 KB, 36 views)

Last edited by sizewell; 04-01-19 at 10:23.
sizewell is offline  
(Post Link) post #8 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
Obstructed front Bank Drainage Port.
Attached Images
File Type: jpg Front Bank obstructed sump entry point.jpg (71.0 KB, 29 views)
sizewell is offline  
(Post Link) post #9 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
Front and rear Bank Head/Block Drainage Channels. Note:- front and rear bank, drainage channel ports nearest the timing chain system - nearest the front of the engine, have no windage plate screening and even were there any, would exhaust the block, into the sump above a windage plate and directly into the region of the rotating journals and counterweights of number 1 & 2 cylinders.

Consequently, It is this authors view, any returning oil and it's relatively low flow rate is being whipped into windage by the rotating crankshaft and journals. This is also true IMHO of the third drainage port, which although having the original windage plate screening the sump, also exhausts the block above the windage plate where cylinder 5 & 6 rotating crankshaft and journals are.
Attached Images
File Type: jpg Front and Rear Bank Drainage Channels.jpg (67.8 KB, 32 views)
sizewell is offline  
(Post Link) post #10 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
Below, the positions where the block/head drainage channels exhaust their oil into the sump, "Above the Windage plate" in the case of the rear bank port nearest the bell housing and the front two, where no Windage Screening exists and again above the level of any windage plate that could have.

A relevant point here is, the two rear bank ports are feeding their oil into the sump in the region where number 1 & 2 cylinder crankshaft counterweights and journals are rotating. Equally true for cylinders 5 & 6. However, they are doing so when the rotating crank and journals are on the upswing, whereby oil, IMHO is being whipped up into windage and also into the cavernous void of the block. I also believe, because the flow rate from the heads is relatively low, but constant, this oil is combining with any blow - by gases, absorbing pollutants and moisture which leads to faster oil degradation. The front port nearest the oil Pump Feed Port is however, on the crankshaft down - swing.
Attached Images
File Type: jpg Short Alfa Windage Plate.jpg (70.3 KB, 20 views)

Last edited by sizewell; 05-01-19 at 14:02.
sizewell is offline  
(Post Link) post #11 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
Below, perhaps a better picture?
Attached Images
File Type: jpg A better picture perhaps..jpg (80.1 KB, 29 views)
sizewell is offline  
(Post Link) post #12 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
Solution for the two rear block/head drains, which now exhaust below the windage plate, free from the influence of the rotating crankshaft and journals.
Attached Images
File Type: jpg Solution for thew two rear drains.jpg (82.3 KB, 30 views)
sizewell is offline  
(Post Link) post #13 of 78 Old 04-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
The front drain modification are a little less tidy than the rear ones. But with the crankshaft on the down swing and the extra metalwork of the windage tray, the influence of the rotating crank should be minimized.
Attached Images
File Type: jpg Extended Windage plate and rear bank drains.jpg (80.4 KB, 22 views)
File Type: jpg Drains and windage.jpg (75.3 KB, 27 views)
File Type: jpg Better baffle picture.jpg (91.3 KB, 23 views)

Last edited by sizewell; 04-01-19 at 14:11.
sizewell is offline  
(Post Link) post #14 of 78 Old 05-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Quote:
Originally Posted by sizewell View Post
The front drain modification are a little less tidy than the rear ones. But with the crankshaft on the down swing and the extra metalwork of the windage tray, the influence of the rotating crank should be minimized.
"I also believe, because the flow rate from the heads is relatively low, but constant, this oil is combining with any blow - by gases, absorbing pollutants and moisture which leads to faster oil degradation".

My reasoning for this assertion is based on the final checks of "Closed Loop Lubrication System". When the oil filter was removed as the CLLS kit was fabricated into it's final design, the filter was laden with what looked like a thick "French Dressing".

As it was left in a drip tray, this mass slowly started to dissolve and separate. The filter was replaced at the same time as the oil was renewed. Subsequent discussions with Scholar Engines, who are re-building my engine, Crankscrapers Head of Engineering in USA and a multitude of engineering articles, persuaded me that this was the cause. Particularly as my water level in the cooling system remained at the same level throughout from the time I had the car on the road.

I went through the process of considering a windage mesh screen, but further reading suggested they only marginally improve things at high RPM. I then considered and am still keen on fitting a Crankshaft Scraper. Tests by Chrysler in the seventies demonstrated that all the engine oil of a big block V8 could rotate around the crankshaft at ~8,000 RPM, completely draining the sump.

The shape, the position, and the low flow rate of returning oil down very large channels from the heads; resulting in the low flow adhering to the walls of the channels by "Skin - Effect", and the proximity of these drains to the rotating crankshaft and journals persuaded me the oil droplets coming out of these orifices were sufficiently small enough to be whipped into windage and very quickly combine with Blow - by products: Pollutants, un-burnt fuel and moisture.

One can add to this, the spray - jets, hitting the fast moving con - rod and underside of the pistons, which probably causes the oil to atomize.

The underside of the block is huge, cavernous even and the surface area enormous. So much so, that I believe, oil slowly drains down from its hot walls, as a very thin film and could indeed be drawn back into windage by the rotating crankshaft and recycled again, to further accumulate blow - by products. The analogy I make with French Dressing is simply because one incorporates the oil into the emulsion very slowly.

In fact, just writing these notes has finally convinced me a Scraper Plate will make a serious improvement in dealing with this phenomenon. Attaching one to the crankshaft bearing caps on the Up - Stroke would ensure that any accrued oil on the crankshaft would be stripped off by the scraper continuously, every revolution. In fact, it would substantially reduce the potential for windage to sustain itself.

The reality is of course, one has to make judgments on the basis of what evidence there is to hand. And outside a Automotive Design Lab, there is always going to be an element of doubt. But logic suggest, there is little difference between a Big Block GM screaming at 8,000 rpm and supporting all of it's oil in orbit around the crankshaft, leaving the sump empty and and Alfa 3.2 JTS at 7200 - 7300 RPM. Crankshaft failure was unquestionably due to oil starvation despite the engine level been checked prior to that fateful run at Bruntingthorpe.

I am now wholly persuaded to fit one and at the very worst, it's effects will be benign. But I do not see that as being the case.
sizewell is offline  
Status: -
AO Member
 
Join Date: Jul 2017
County: -
Posts: 468
Sizewell,

I’m unable to reply to you for some reason on my s-v6 track car thread for some reason.

I am doing track days at Bedford and donington in February and March.

I currently have Millers CFS 5w40 NT+ engine oil, but it’s abit pricey to be swapping out after a track day.

Would you recommend any other oil to use for the days and should I replace engine oil after the track day?

I’ve found this other Millers engine for motorsport if you think it’s suitable?

Cheers

Quote:
Originally Posted by sizewell View Post
Quote:
Originally Posted by alfaromeo939s View Post
very interested in following this

I ha my brera 3.2 rebuilt last year and have converted it into a track car so i am interested in the route you go down
The front drain modification are a little less tidy than the rear ones. But with the crankshaft on the down swing and the extra metalwork of the windage tray, the influence of the rotating crank should be minimized.
Attached Images
File Type: jpg D4D55791-A343-4008-AF3C-A80ECD02A4BD_1546862602601.jpg (15.2 KB, 16 views)
File Type: png F1928690-95C0-4786-82EB-ECCD68639B2F_1546862616022.png (281.3 KB, 29 views)
alfaromeo939s is offline  
(Post Link) post #16 of 78 Old 08-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by alfaromeo939s View Post
Sizewell,

I’m unable to reply to you for some reason on my s-v6 track car thread for some reason.

I am doing track days at Bedford and donington in February and March.

I currently have Millers CFS 5w40 NT+ engine oil, but it’s abit pricey to be swapping out after a track day.

Would you recommend any other oil to use for the days and should I replace engine oil after the track day?

I’ve found this other Millers engine for motorsport if you think it’s suitable?

Cheers
Hi,

I'm sorry for not replying earlier, but only just saw your post yesterday and things still a bit hectic.

But to be honest, it was also; in part, to think of a response. These engines are very expensive to maintain and just physically doing some work on them is not cheap.

The work I am undertaking on my Brera engine and, once it replaces my 159's the work I will be doing to that, is a real labour of love. And it needs to be, as pockets need to be a lot deeper if mistakes are made.

Advice on type of oil? I love what you are doing with your car and if mine takes much longer to get back, my license will have been revoked and the only place I will be able to drive it will be on a a track.

I cannot in all conscience and will not on principle give advice on what people should do with their cars. Any mistakes must be their own, which means you need to do a lot of digging for information - there is a lot to be had, as I have found.

For instance, I had in my last post concluded I would fit a scraper plate to try and disrupt windage and in particular recover the spent spray jet oil faster and return it to the sump. But speaking with my engine builder, his advice was not to. He showed me the sump from one vehicle which had cracks in the baffle/windage plate due to vibration. He also showed me a scraper plate which was fixed by the sump/block bolts. It too had suffered fatigue and was showing signs of cracking.

My engine failed, not for lack of oil, but most likely because of the delay in the oil being recirculated to the sump. Essentially, the engine capacity is too small and the oil gets no settling time to allow entrained air to precipitate out. It is not for nothing, manufacturers chose oils with good anti - foaming characteristics.

Windage will drag combustion by - products; air, hydrocarbons and moisture as well as burnt oil, spent lubricating oil and spray jet oil, into suspension and unless the returning oil is allowed time in the sump for all this entrained air and moisture to precipitate out, it is simply taken up by the oil pump and compressed into the oil and returned to the galleries/oil-ways.

All the articles I have read state, whilst these components remain "Dissolved in the Oil", it is less problematic. But restrictions in galleries cause any dissolved components to precipitate out into entrainment. This happen on the inner radii/edge of any restriction, but successive restrictions are very difficult to analyze, other than to say, there is a very rapid change of dissolved components into entrained components.

The net effect being, the "Hydraulic Nature" of lubricating oil is lost and it becomes compress - able. The oil becomes spongy and exerts less pressure on essential components such as tensioners. (Problem Number One).

However, with dissolved components, reversing to entrained air/moisture, one gets two problems for the price of one.

The first, I have given above. The second is:- the further away from the oil pump, the greater the pressure drop. Also the oil has been exposed to a greater temperature gradients - vis a vis it is hotter. The pressure drop itself will cause the bubbles to expand and the increased temperature causes a reduction in viscosity, so the bubbles can precipitate out faster.

This is why my engine suffered damage to number four and five - five failing, big end bearings. Why four and five, when number six is furthest away? because the oil feed to number one and number six journals are not Siamese twins.

Meaning, number One Main bearing and number Four Main Bearing, supply only Number One Cylinder Big End Bearing and Number Six Cylinder Big End Bearing, respectively.

Big Ends Two and Three share oil from Main Bearing Number Two. And Big Ends Four and Five share oil from Main Bearing Number Three.

Accordingly, the physics state; "the expanding bubbles, due to reducing pressure and increasing temperature can withstand high sheer pressures, to the extent that they can prevent oil from flowing." Effectively running bearings dry!

It has been suggested to me, a second function of the spray jets is to help remove entrained air/moisture, but whilst entirely plausible, I think the distances are too short to be that effective. Of course, they may more effectively, if the degree of entrained Air/Moisture is low. (Problem number Two).

One cannot prevent Combustion by - products, air and moisture from being absorbed into oil. But there are ways to reduce it and it's effects.

Likewise, one cannot prevent absorbed products from precipitating out into entrainment - bubbles in the oil. But one can reduce it.

The simplest way of minimizing the problem is:-

1) Change oil on a very low mileage basis.

2) Eliminating restrictions, mitigates Problems One and Two.

3) Increase the capacity of the oil in the engine so it has a longer rest time before it is
recirculated.

4) Avoid prolonged high revolutions in low gears; where blow - by is greatest, as is the vortex created by the rotating crankshaft and journals, whereby these products can be more quickly absorbed by the oil and foaming becomes a major issue.

With this engine and it's low capacity of oil, delayed returning oil, can result in this foam being drawn up by the oil pump and compressed into the oil - ways, because the sump level has dropped - at 7,000 rpm the pump can empty the sump twice as fast as at 3,500 rpm, the level having dropped and foam (aerated oil) pulled into the pump.

I write these paragraphs, not just as a reply to you, but also for my own benefit. I cannot advise you on what oil to use other than to stick with that recommended. Thinking off the top of my head, no racing team would re - use oil and given their engines are re - built on a regular basis, top grade oil is most beneficial in this instance.

The fact is, your engine is not new and will already have suffered wear. So a top grade oil, which is very effective with tight bearings, may less effective with an engine with bearings less so.

Understanding the problems better; new oil, is always going to be better than old oil, even if it is the highest spec. Avoiding entrained air is key and old oil may have had time to rest and disperse air, but there is still the issue of by - products, trapped in the oil, such that it's effectiveness as both a lubricant and a hydraulic medium is reduced.

My choice, and this is not a recommendation, I will use what Alfa recommend. Even though my rebuilt engine is effectively new and bearings are "Tight". But on the track, I would spend some time between runs to allow my engine to recover, recheck the oil, then steadily drive home. AND IMMEDIATELY DO AND OIL AND FILTER CHANGE.

Good luck with your car.

Brian.

Last edited by sizewell; 08-01-19 at 19:50.
sizewell is offline  
Status: -
AO Member
 
letholdus's Avatar
 
Join Date: Mar 2018
Location: south island
County: New Zealand
Posts: 92
im slowly modifying my 159 3.2 aswell

i've bought a set of performance camshafts and valve-springs from mace engineering. their own tests have made gains of roughly 30rwkw's with a dynotune etc.

191kw factory , plus 30 odd rwkw's from the cams. would roughly make 230ish kw from the motor

I'm going to get the fitted and tuned by the performance workshop next door to me.

Popped next door the other day and the guys there said its a simple swap and dyno tune with a bit of tweaking.

I've already installed a custom cat back free flow exhaust system and installed a custom air intake with Silicone couplers and hose from the MAF into a pressurised unit with a simota mushroom filter. It doesn't make a racket like those ram intakes but it has made a definite difference without losing low end torque.

Intake Duration (@0.050"): 210
Exhaust Duration (@0.050"): 210
Lift: Standard

https://www.maceengineering.com.au/e...ducts/CAM666-A
Attached Images
File Type: jpg Capture.JPG (51.5 KB, 15 views)
sizewell likes this.

Last edited by letholdus; 09-01-19 at 08:13.
letholdus is offline  
(Post Link) post #18 of 78 Old 09-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by letholdus View Post
im slowly modifying my 159 3.2 aswell

i've bought a set of performance camshafts and valve-springs from mace engineering. their own tests have made gains of roughly 30rwkw's with a dynotune etc.

191kw factory , plus 30 odd rwkw's from the cams. would roughly make 230ish kw from the motor

I'm going to get the fitted and tuned by the performance workshop next door to me.

Popped next door the other day and the guys there said its a simple swap and dyno tune with a bit of tweaking.

I've already installed a custom cat back free flow exhaust system and installed a custom air intake with Silicone couplers and hose from the MAF into a pressurised unit with a simota mushroom filter. It doesn't make a racket like those ram intakes but it has made a definite difference without losing low end torque.

Intake Duration (@0.050"): 210
Exhaust Duration (@0.050"): 210
Lift: Standard

https://www.maceengineering.com.au/e...ducts/CAM666-A
Sound good Leth.

I bought a uprated timing chain kit from Mace and I could not believe the price. Their service was superb, bigger delay getting it delivered in UK than it was for them to get it to UK. Excellent service. But it was within two weeks.

Your camshafts were a very good price. I went for Colombo Bariani simply because I have had four sets from them over the years and been very happy with their performance. The duration on the C.B.'s is 278/278, as opposed to Alfa's 254/250. The differences between yours and mine could well be down to the way Mace have contoured the lobes, i.e. fast opening and certainly from the pictures, they look very broad - dare I say "Squarish".

It will be good to know how well things progress for you. I am still probably a couple of months away before the car is ready to take the rebuilt engine. In the mean time I am just documenting the changes I have made to the engine and trying to keep a record of why I made these changes.

Good luck.
sizewell is offline  
(Post Link) post #19 of 78 Old 09-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by sizewell View Post
Sound good Leth.

I bought a uprated timing chain kit from Mace and I could not believe the price. Their service was superb, bigger delay getting it delivered in UK than it was for them to get it to UK. Excellent service. But it was within two weeks.

Your camshafts were a very good price. I went for Colombo Bariani simply because I have had four sets from them over the years and been very happy with their performance. The duration on the C.B.'s is 278/278, as opposed to Alfa's 254/250. The differences between yours and mine could well be down to the way Mace have contoured the lobes, i.e. fast opening and certainly from the pictures, they look very broad - dare I say "Squarish".

It will be good to know how well things progress for you. I am still probably a couple of months away before the car is ready to take the rebuilt engine. In the mean time I am just documenting the changes I have made to the engine and trying to keep a record of why I made these changes.

Good luck.
Below are images of the filter cooler. The initial modified one worked well with my CLLS but since then have I fretted over:-

a) The lack of any real oil cooling this unit performs. Actually some commentators have suggested
it is more an "Oil Pre-heater".

b) Poor water cooling due to lack capacity in the radiator and the fact that the climate control
element is located in front of it.

So, I have been searching for a way to incorporate an external oil cooler, whilst at the same time, considering whether I should disconnect the water side to the Filter/cooler Unit. But, it seemed whatever I did would look very Heath - Robinson. Indeed, I was going to dispense with the Climate control and fit a larger capacity radiator.

However, having just got my spare Filter/Cooler back from Nigel, suitably modified, I decided to take another look at how it could be done - neatly.

The second picture is of the Filter/cooler with the Heat Exchanger removed. The plan now is, to have a 25 mm. plate machined up, drilled and shaped to fit where hitherto the heat exchanger was.

It will be drilled and tapped to take the four ports which can be seen in the image; go and return for the external oil cooler, and go and return for the external "Extra" water radiator.

The beauty of this is, I do not have to monkey about trying to find the best way to couple in these new external units. Secondly, the braided hoses for both units will come out exactly where I would want them - At The Front Of The Engine, where space can be found behind the front bumper.

Further observations being, a conventional filter housing and element can be Plumbed in with it's base plate - Demon Tweeks and the Alloy block can de drilled to insert both an Oil Temperature Sensor and a Water Temperature Sensor. The original could still have an element fitted, or indeed it can simply left out of the housing.

The oil temperature sensor, can pick up the leg from the block/oil pump/sump and give a pretty accurate indication of the Working Temperature of the oil. This is also true of the Water Temperature Sensor.
sizewell is offline  
(Post Link) post #20 of 78 Old 09-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by sizewell View Post
Below are images of the filter cooler. The initial modified one worked well with my CLLS but since then have I fretted over:-

a) The lack of any real oil cooling this unit performs. Actually some commentators have suggested
it is more an "Oil Pre-heater".

b) Poor water cooling due to lack capacity in the radiator and the fact that the climate control
element is located in front of it.

So, I have been searching for a way to incorporate an external oil cooler, whilst at the same time, considering whether I should disconnect the water side to the Filter/cooler Unit. But, it seemed whatever I did would look very Heath - Robinson. Indeed, I was going to dispense with the Climate control and fit a larger capacity radiator.

However, having just got my spare Filter/Cooler back from Nigel, suitably modified, I decided to take another look at how it could be done - neatly.

The second picture is of the Filter/cooler with the Heat Exchanger removed. The plan now is, to have a 25 mm. plate machined up, drilled and shaped to fit where hitherto the heat exchanger was.

It will be drilled and tapped to take the four ports which can be seen in the image; go and return for the external oil cooler, and go and return for the external "Extra" water radiator.

The beauty of this is, I do not have to monkey about trying to find the best way to couple in these new external units. Secondly, the braided hoses for both units will come out exactly where I would want them - At The Front Of The Engine, where space can be found behind the front bumper.

Further observations being, a conventional filter housing and element can be Plumbed in with it's base plate - Demon Tweeks and the Alloy block can de drilled to insert both an Oil Temperature Sensor and a Water Temperature Sensor. The original could still have an element fitted, or indeed it can simply left out of the housing.

The oil temperature sensor, can pick up the leg from the block/oil pump/sump and give a pretty accurate indication of the Working Temperature of the oil. This is also true of the Water Temperature Sensor.
Hitherto, omitted pictures:- Plus Dynamometer Plot of CLLS 159 Q4 and Standard 40,000 is Brera SV.
Attached Images
File Type: jpg Initial Cooler Mods.jpg (87.2 KB, 28 views)
File Type: jpg Filter Cooler Further modification..jpg (79.4 KB, 29 views)
Attached Files
File Type: pdf Nigels and Brians Plots.pdf (111.6 KB, 31 views)
sizewell is offline  
Status: -
AO Silver Member
 
Chris155's Avatar
 
Join Date: Jan 2014
Location: United Kingdom
County: Cheshire
Posts: 2,947
Quote:
Originally Posted by sizewell View Post
Hitherto, omitted pictures:- Plus Dynamometer Plot of CLLS 159 Q4 and Standard 40,000 is Brera SV.
176, 164, 167, 167bhp WHP figures are very poor for an engine that supposedly produces 256 FW BHP, the transmission losses are huge.
Chris155 is online now  
(Post Link) post #22 of 78 Old 10-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by Chris155 View Post
176, 164, 167, 167bhp WHP figures are very poor for an engine that supposedly produces 256 FW BHP, the transmission losses are huge.
The dyno plot is here for reference; completeteness.

That observation has been made before. Nothing untoward was said by Clive Atthowe, where the Dynamometer tests were done.

These plots have been run past my Engine Builder and benchmarked by the engineer involved. The plots also, very much follow those of the 159 Q4, which was modified in Australia. The guy undertook to Dynamometer test his car before and after the mods were done, which helped me a lot as I had none from before modification.

Both Colombo Bariani and Autodelta have these figures and again, no comment was made about the apparent discrepancy. The kink at the top end of the 159 was attributed to a misfire. But as was pointed out, the AFR does not support that theory, but more likely to be due to an inlet tract anomaly/resonance. Forty years of building racing engines and I am not going to argue!

The 159 will go back to Atthowe after modifications, for re - testing. My thoughts on the issue are simply there is something about the way the Test Rig works, but I am not concerned about it. The important thing for me here is to complete the rebuild , whilst documenting the changes.

The Brera SV is in spanking condition, yet still shy of the 159s figures. It is probable, Nigels Brera will not be modified. He is a long time Alfa man and quite a purist, apart from being a damned good hydraulics man and good mate. Whilst his car performs as well as it does, he is happy to leave her alone. My suspicion is, he recognises its rarity, wants to keep it original and finds himself owning the car he has loved from when it was first introduced

I could never justify buying one, given its poor performance and economy. Unquote. It was only after I took him for a spin in my 3/4 modified Q4, that he spent weeks, covertly searching for the car he has now, after pleading with his wife to let him buy it. And it is a beauty.

This blog, I hope will be of some use to those members who have 159s, Breras And Spiders; 3.2s . I will continue to post details of my work and My justification for making them. If it is of benefit to other owners, fine.

But I really must concentrate on bringing this together and not be distracted by minutiae.

It has taken so long to get this far and any mistakes can be expensive. For those that wish to know more about the various Dynamometer machines there are about, they can easily research for themselves.
sizewell is offline  
(Post Link) post #23 of 78 Old 14-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Quote:
Originally Posted by sizewell View Post
Hitherto, omitted pictures:- Plus Dynamometer Plot of CLLS 159 Q4 and Standard 40,000 is Brera SV.
In preparation for the Timing chain install, I have made a start on the second Inlet VVT Sprocket/Rotor and the two Exhaust Sprocket/Rotors.

Below is a picture of the rear bank exhaust Sprocket and as can be seen, there is a lot of white metal debris from the failed crankshaft bearings.

The second picture is of the VVT Solenoid, of which can be seen the flats Alfa cut across the inlet port to advance port and inlet port to retard port. All four VVT solenoids were removed some time ago whilst I was exploring the mechanisms and considering what I could do. Their screens too had acquired a fair bit of white metal. However, had Alfa not cut those flats into the VVT port partitions, the meshes would have contained all the detritus and the VVT Sprocket/Rotor voids would not have required dis - assembling.

On another note, regarding the internal spring pressure on the rotors, the Inlet Camshaft Rotors have considerably less spring bias to hold them in the retard position. However, the Exhaust Camshaft Rotors are biased very strongly in the advance position.

I know modern engines use valve timing to assist emission control, and that on this Alfa Engine the exhaust timing is set to max advance on start - up. But it appears to me, hydraulic pressure needs to be considerably higher to rotate the exhausts than for the inlets.

I wonder if anyone can throw light on this. Is this as a function of some inter - relationship with the manifold cats? Or simply because the inlet camshaft timing has a greater bearing on performance than the exhaust camshafts and thus it is worthwhile having them respond more quickly than the exhausts?

I am also considering leaving the lock - pin out of the VVT's as the heavy bias of the springs will always drive them back to their "Park Positions". It really is simply about improving the throttle/engine response time. Only when the void nearest the lock - pin housing has started to fill and rotate, are the inlet ports for the remaining voids exposed - due to the rotation of the phasor, so there is a delay due to the hydraulics first having to un - lock the pin, then the first void fills from the pin cavity/port and as the phasor rotates, the other void ports become exposed and they too fill.

In the Idle/engine off position , the Inlet VVT Solenoids advance port is always open to drain into the heads so the camshaft will always return to the max retard position.

Equally at idle, the Exhaust VVT Solenoids retard port is always open to drain into the heads so the camshaft will always return to the max advance position.
Attached Images
File Type: jpg Fouled VVT.jpg (72.2 KB, 13 views)
File Type: jpg Culprits.jpg (95.6 KB, 13 views)

Last edited by sizewell; 14-01-19 at 15:34.
sizewell is offline  
(Post Link) post #24 of 78 Old 15-01-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by sizewell View Post
In preparation for the Timing chain install, I have made a start on the second Inlet VVT Sprocket/Rotor and the two Exhaust Sprocket/Rotors.

Below is a picture of the rear bank exhaust Sprocket and as can be seen, there is a lot of white metal debris from the failed crankshaft bearings.

The second picture is of the VVT Solenoid, of which can be seen the flats Alfa cut across the inlet port to advance port and inlet port to retard port. All four VVT solenoids were removed some time ago whilst I was exploring the mechanisms and considering what I could do. Their screens too had acquired a fair bit of white metal. However, had Alfa not cut those flats into the VVT port partitions, the meshes would have contained all the detritus and the VVT Sprocket/Rotor voids would not have required dis - assembling.

On another note, regarding the internal spring pressure on the rotors, the Inlet Camshaft Rotors have considerably less spring bias to hold them in the retard position. However, the Exhaust Camshaft Rotors are biased very strongly in the advance position.

I know modern engines use valve timing to assist emission control, and that on this Alfa Engine the exhaust timing is set to max advance on start - up. But it appears to me, hydraulic pressure needs to be considerably higher to rotate the exhausts than for the inlets.

I wonder if anyone can throw light on this. Is this as a function of some inter - relationship with the manifold cats? Or simply because the inlet camshaft timing has a greater bearing on performance than the exhaust camshafts and thus it is worthwhile having them respond more quickly than the exhausts?

I am also considering leaving the lock - pin out of the VVT's as the heavy bias of the springs will always drive them back to their "Park Positions". It really is simply about improving the throttle/engine response time. Only when the void nearest the lock - pin housing has started to fill and rotate, are the inlet ports for the remaining voids exposed - due to the rotation of the phasor, so there is a delay due to the hydraulics first having to un - lock the pin, then the first void fills from the pin cavity/port and as the phasor rotates, the other void ports become exposed and they too fill.

In the Idle/engine off position , the Inlet VVT Solenoids advance port is always open to drain into the heads so the camshaft will always return to the max retard position.

Equally at idle, the Exhaust VVT Solenoids retard port is always open to drain into the heads so the camshaft will always return to the max advance position.

Further to the above, I am now entirely convinced of the reasons for the for timing chain stretch, premature tensioner and guide wear and rear bank exhaust camshaft errors.

Both the lower timing chain tensioner and the rear bank upper timing chain tensioner are, along with the hydraulic feed for the rear bank exhaust camshaft, the very last items to receive oil through the convoluted galleries of the block and their attendant restrictions.

However, having just overhauled the VVT phasors, it is clear why, notwithstanding the aforementioned issues, the rear exhaust bank camshaft is prone to throwing up codes. Leaving one of the two exhaust camshaft phasors untouched for reference, the second one was disassembled for cleaning.

Having completed the two Inlet Phasors, and deliberately left the lock pin out, they were both checked for rotational pressure and smoothness of operation. There is only one position, when the phasors are re - assembled, that the internal spring will function linearly and as such the phasors - less their lock pins can be rotated just gripping them with both hands. No Other Assembly Position Can Achieve This. Also, as one of the inlet Phasors had been left in its original state, it was clear this was the way the factory assembled them.

Adopting the same approach with the exhaust Phasors, it soon became apparent; a, the phasors cannot be rotated by hand and b, even when connected to the camshaft, it is extremely difficult to rotate the phasor to end - stop (max retard). Again the lock pins had been omitted to facilitate these checks.

Several attempts to find another position, which would lighten the internal spring load to something similar to the inlet Phasors to no avail. Only one position could be found, but the lack of spring pressure would result in the rotor not returning to the lock position so clearly this was not right.

Having re - assembled the first exhaust Phasor, then removed the lock pin of the second "Reference Phasor", the same exercise was carried out.

It is intended in the next few days to have the phasors tested for rotational torque. But it is clear from these tests, considerably higher pressure is required to rotate the exhaust phasors than the inlet phasors. Not only is the force required much greater, but; although it may be just my perception, it is not linear, as with the inlets.

In the next few days, I intend to have the phasors tested to determine the rotational torque required for all four, but it is clear to me, with the front bank exhaust phasor, immediately off the main front bank gallery, nearest the oil pump, and the rear exhaust phasor furthest away, speed of operation will differ dramatically.

However I fail to understand why, given the phasors are hydraulically driven in both directions, such huge spring pressure should be necessary, particularly as the inlets seem to be so much lower.

A key may be the inlet camshafts are fully retarded on start up, whereas the exhaust are fully advanced. So perhaps the pressure is intended to withstand the thrust face pressure of the valve train upon the camshaft.

But they cannot move until the oil pressure is sufficient to release the lock pin. So under normal circumstances it seems excessive, unless it was recognized that the oil pressure of the rear bank is not sufficient to overcome the thrust face loading of the valve train and consequently timing accuracy would suffer. This being the case, whilst trying to quantify the changes I have made with my CLLS, the increased pressure afforded by the rear bypass line, clearly helps exhaust camshaft valve timing, given the internal spring pressure the oil has to overcome.

However even with this line, I doubt the exhaust camshaft phasors range will be fully exploited. A line would probably have to be taken directly from the oil cooler/filter to the VVT solenoid. But this would be taking it too far. But it may be a further factor in limiting this engines power potential.

However, such is the strength of the spring pressure, I shall be leaving the Exhaust camshafts permanently unlocked. I am still mulling over whether to do the same for the inlets and as their phasors voids are at "Back - stop", it may result in a little improvement in VVT response speed.

Last edited by sizewell; 04-02-19 at 13:55.
sizewell is offline  
(Post Link) post #25 of 78 Old 04-02-19 Thread Starter
Status: -
AO Silver Member
 
Join Date: Dec 2009
Location: United Kingdom
County: Suffolk
Posts: 3,000
Chilling

Quote:
Originally Posted by sizewell View Post
Further to the above, I am now entirely convinced of the reasons for the for timing chain stretch, premature tensioner and guide wear and rear bank exhaust camshaft errors.

Both the lower timing chain tensioner and the rear bank upper timing chain tensioner are, along with the hydraulic feed for the rear bank exhaust camshaft, the very last items to receive oil through the convoluted galleries of the block and their attendant restrictions.

However, having just overhauled the VVT phasors, it is clear why, notwithstanding the aforementioned issues, the rear exhaust bank camshaft is prone to throwing up codes. Leaving one of the two exhaust camshaft phasors untouched for reference, the second one was disassembled for cleaning.

Having completed the two Inlet Phasors, and deliberately left the lock pin out, they were both checked for rotational pressure and smoothness of operation. There is only one position, when the phasors are re - assembled, that the internal spring will function linearly and as such the phasors - less their lock pins can be rotated just gripping them with both hands. No Other Assembly Position Can Achieve This. Also, as one of the inlet Phasors had been left in its original state, it was clear this was the way the factory assembled them.

Adopting the same approach with the exhaust Phasors, it soon became apparent; a, the phasors cannot be rotated by hand and b, even when connected to the camshaft, it is extremely difficult to rotate the phasor to end - stop (max retard). Again the lock pins had been omitted to facilitate these checks.

Several attempts to find another position, which would lighten the internal spring load to something similar to the inlet Phasors to no avail. Only one position could be found, but the lack of spring pressure would result in the rotor not returning to the lock position so clearly this was not right.

Having re - assembled the first exhaust Phasor, then removed the lock pin of the second "Reference Phasor", the same exercise was carried out.

It is intended in the next few days to have the phasors tested for rotational torque. But it is clear from these tests, considerably higher pressure is required to rotate the exhaust phasors than the inlet phasors. Not only is the force required much greater, but; although it may be just my perception, it is not linear, as with the inlets.

In the next few days, I intend to have the phasors tested to determine the rotational torque required for all four, but it is clear to me, with the front bank exhaust phasor, immediately off the main front bank gallery, nearest the oil pump, and the rear exhaust phasor furthest away, speed of operation will differ dramatically.

However I fail to understand why, given the phasors are hydraulically driven in both directions, such huge spring pressure should be necessary, particularly as the inlets seem to be so much lower.

A key may be the inlet camshafts are fully retarded on start up, whereas the exhaust are fully advanced. So perhaps the pressure is intended to withstand the thrust face pressure of the valve train upon the camshaft.

But they cannot move until the oil pressure is sufficient to release the lock pin. So under normal circumstances it seems excessive, unless it was recognized that the oil pressure of the rear bank is not sufficient to overcome the thrust face loading of the valve train and consequently timing accuracy would suffer. This being the case, whilst trying to quantify the changes I have made with my CLLS, the increased pressure afforded by the rear bypass line, clearly helps exhaust camshaft valve timing, given the internal spring pressure the oil has to overcome.

However even with this line, I doubt the exhaust camshaft phasors range will be fully exploited. A line would probably have to be taken directly from the oil cooler/filter to the VVT solenoid. But this would be taking it too far. But it may be a further factor in limiting this engines power potential.

However, such is the strength of the spring pressure, I shall be leaving the Exhaust camshafts permanently unlocked. I am still mulling over whether to do the same for the inlets and as their phasors voids are at "Back - stop", it may result in a little improvement in VVT response speed.

================================================== =============


My engine build is now at a critical stage and still I fret over the function of the VVT rotors. So much so that I took them up, after cleaning to my engine builders. I commented on how hard it is to rotate the exhaust VVT rotors and a few observations were made.

1, Exhaust vvt timing is less important in determining real power gains. 2, There is more than sufficient oil pressure to overcome the spring pressure - based on unrestricted oil flow. 3, The exhaust VVT is more important wrt emission control. Starting the engine with maximum advance on the exhaust camshaft will reduce the "Light - off" time of the manifold mounted Catalytic Converters, getting them up to working temperature faster.

Question? could it be that the high pressure of the internal spring of the exhaust VVT Rotors, in conjunction with inadequate oil pressure causes the exhaust camshafts to be sluggish and remain over advanced (mean operating), such that gases are exhausted earlier than normal, after light - off temperature has been achieved, thus causing the catalytic converters to run excessively hot? Answer - needs investigating.

However, remaining nervous as we are now at a point where the camshafts are about to be fitted and the new timing chain system installed, and engine timed, I decided I would look again at how the VVT Rotors function.

There is no question they have gone back together correctly as a "shadow" of the voids and lock pin is faintly imprinted upon the inside of the rotor voids. So I will for my benefit, detail how I believe the system functions. If it is of any use to others then fine!

Exhaust Camshaft Rotor/Phasor.

The internal spring of the exhaust VVT, biases the internal rotor in the "Fully Advanced Position". The spring pressure is considerable but this author believes this is to help overcome the tendency of the exhaust camshaft to retard. as it comes up against the thrust face of the camshaft and valve train. In this position the internal vanes are at end - stop, fully advanced.

However, it may also be intended to resist the extra load exerted by the JTS Pump which is mounted on the end the front bank exhaust camshaft. Both exhaust camshaft spring pressures are the same, so this in itself suggests the internal spring on the rear bank exhaust Phasor would make it slower to respond!!!!!

However, to create a stable idle, the camshafts must be prevented from "Fluttering" (Emissions Tests?). So in this position, the lock Pin simply retains the camshaft at end - stop, until the VVT solenoid opens - on instruction from the ECU - and oil pressure forces it out and the exhaust camshaft then starts to retard.

This delays exhaust gases (stays in the cylinder longer) and reduces the exhaust gas temperature to a point where it is sufficient to sustain the catalytic converters at their optimum - Light off temperature hitherto being achieved fast with the maximum advance and now only just sustained by the reduced advance angle of the exhaust camshaft timing.

Inlet Camshaft Rotor/Phasor.

The internal spring of the Inlet Camshaft Phasor/rotor biases the inlet camshaft in the maximum advance position although the pressure is not as great as with the exhaust Phasor/Rotor. However, it is held in the fully retard position by its lock Pin. The thrust face of the camshaft and the valve train will tend to force it in this direction in any case, but it is driven back into the static retard position by oil from the Inlet VVT Solenoid - under normal operating conditions.

Should oil pressure fail, the author believes the thrust face of the camshaft in conjunction with the valve train would be sufficient to force the camshaft to retard fully; against the internal spring pressure, and the Lock Pin would then engage to hold it in it's "Static Reset" position.

When the inlet VVT Solenoid - under instruction from the ECU - allows oil to flow into the Rotor, the Lock Pin is driven out and the inlet camshaft, assisted by the, albeit lower pressure internal spring, starts to advance against the thrust face of the camshaft and the valve train.

Last edited by sizewell; 04-02-19 at 15:25.
sizewell is offline  
Reply

Go Back   Alfa Romeo Forum > Supported Alfa Romeo Models > Technical & Vehicle Assistance > Alfa 159, Brera & 946 Spider

Tags
brera , jts , modified , rebuild

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome