Brera 3.2 JTS Q4 SV 48,000 miles Timing Chain - Page 6 - Alfa Romeo Forum
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Originally Posted by jbsmith1 View Post
...
.
.
.
arh ha let the conspiracies begin! I wonder what the pressures will reveal?
on the subject of "Let the conspiracies begin"!
What happened to my wear reducing ZDDP!
https://www.youtube.com/watch?v=lQ6N...ature=youtu.be
https://www.youtube.com/watch?v=xILCJc2o_L8

...and should we add some back!

Last edited by jbsmith1; 22-11-15 at 13:36.
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I don't get why you want to push a thicker oil round your engine, it doesn't need it. All your bearing pressures will change and tensioner pressures too, and you'l have higher power losses working the pump harder. If you want to have tighter temperature control then look at improving your cooling systems and leave the oil alone.
Oil Pressure will be limited to the blow - off value of the Oil pump, which as Alfa quote the system pressure; depending upon RPM, is max 6 bar. So increased thickness will result in higher back pressure on the blow - off valve, causing it to reduce pressure at outlet for bearings and tensioner. This valve ensures pressures in the system are no greater the n 6 bar. However, the thicker the oil, the greater the inertia in moving it around; pressure sampled at the input to the block differing greatly from those at the outlet of the galleries! So, you could still be suffering from oil starvation. I.e. thicker oil, greater the pressure gradient from oil pump to bearings/camshafts and tensioners.
Only opinion, but thinner oil, better cooling is where I would come from. If a thinner oil is better for cold starting, then why not maintain that once the engine is warm? Better oil cooling perhaps? Engine temperature "X", Oil temperature, "X" - "Y Oil Cooler value". Improve the running viscosity, without changing the grade of oil. Just a thought.
Kind Regards,
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Last edited by sizewell; 22-11-15 at 14:45. Reason: Just a thought. Would A bigger water radiator not help maintain greater viscosity?
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Oil Pressure will be limited to the blow - off value of the Oil pump, which as Alfa quote the system pressure; depending upon RPM, is max 6 bar. So increased thickness will result in higher back pressure on the blow - off valve, causing it to reduce pressure at outlet for bearings and tensioner. This valve ensures pressures in the system are no greater the n 6 bar. However, the thicker the oil, the greater the inertia in moving it around; pressure sampled at the input to the block differing greatly from those at the outlet of the galleries! So, you could still be suffering from oil starvation. I.e. thicker oil, greater the pressure gradient from oil pump to bearings/camshafts and tensioners.
Only opinion, but thinner oil, better cooling is where I would come from. If a thinner oil is better for cold starting, then why not maintain that once the engine is warm? Better oil cooling perhaps? Engine temperature "X", Oil temperature, "X" - "Y Oil Cooler value". Improve the running viscosity, without changing the grade of oil. Just a thought.
Kind Regards,
Yep we're both saying the same thing and giving the same advice to Mash4077, if he feels are answers arn't right he can always start a new topic and ask a wider audience.
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Yep we're both saying the same thing and giving the same advice to Mash4077, if he feels are answers arn't right he can always start a new topic and ask a wider audience.
Now! Now! JB, that's naughty. There is nothing wrong in playing devils advocate. Just as he was with differing wheel sizes on the Q4 I believe! He is no more willing to risk his toy than you or I. But it would be less frustrating, if he did the basics first! None the less, I like it.
Kind Regards,
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Now! Now! JB, that's naughty. There is nothing wrong in playing devils advocate. Just as he was with differing wheel sizes on the Q4 I believe! He is no more willing to risk his toy than you or I. But it would be less frustrating, if he did the basics first! None the less, I like it.
Kind Regards,
My point was there are other's on the forum better qualified than us who can answer his question better and may not be in this thread titled Timing Chain, I could have easily ignored his questions but I've spent time answering, nothing nasty ever intended Mash hence the thumbs emotion at the end.
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I don't get why you want to push a thicker oil round your engine, it doesn't need it. All your bearing pressures will change and tensioner pressures too, and you'l have higher power losses working the pump harder. If you want to have tighter temperature control then look at improving your cooling systems and leave the oil alone.
Quote:
Now! Now! JB, that's naughty. There is nothing wrong in playing devils advocate. Just as he was with differing wheel sizes on the Q4 I believe! He is no more willing to risk his toy than you or I. But it would be less frustrating, if he did the basics first! None the less, I like it.
Kind Regards,
well, "doing the basics" from my side was asking the dealers. being older each day makes me wiser: should stop listening those buggers earlier and start using my brain instead. ask real specialists instead of salesman!

oket guys, thanks, will take your advice and order the grade prescribed by AR, just the Nano Oil from Millers

regards, Preddy
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Originally Posted by Cuore_Sportivo_155 View Post
Viscosity is the first line of defense against bearing wear, but is not effective to combat cam/ring/piston skirt and chain wear. You need anti-wear additives there. MoDTC or MoDTP are good, plenty of ZDDP aswell but also calciumsulfonate is both a detergent and anti-wear agent.
Quote:
Originally Posted by Jbsmith1
....
I've read owners of all makes saying they are following all the manufacturers advice for oil spec and change intervals but how they are still being "caught out" with premature timing wear codes popping up, and upon inspection worn guides/sprocket and chains.

So we are now looking at the oil as a possible culprit and is anything changing that may increase wear right under our noses!

Are we short on vital anti-wear additives ZDDP's? I've read on many articles how the reduction has gone from 2000+ppm in the 1970's to now just being maximum of 600-800ppm, and this is mainly to reduce poisoning of the catalytic converter...well thats fine but at what cost, people are spending thousands on worn timing system repairs...should we boost our ZDDP's?
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Originally Posted by JOHN156VELOCE
I dont think the problem is the oil type used, the problem is the unrealistic 18 or 21 k oil change intervals imposed by the marketing departments to make the car look cheaper to run in the first 3 years.
It would be great to compare the internals of an 100k engine run with 8 or 10k oil changes to one thats stuck to 18 or 21k, especially as in the real world people tend to stretch them a bit longer.
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Originally Posted by Cuore_Sportivo_155
In the 1970's and until API SJ there was no upper limit on ZDDP, but no on the shelf oil used a lot.

I don't think the problem is lack of ZDDP, but rather the lack of oxidative stability. The detergents are what first attacks the formation of acids, but if these are used, Moly (MoDTC or MoDTP) will be consumed and in the end the ZDDP which should have been used to prevent wear.

The answer is using a more stout oil for a realistic interval. Rather than looking for reasons not to be in the severe service category, look for reasons to apply severe service.


Avoid ACEA C-rated oils (I'm even going off them for my DPF equipped car), avoid ILSAC rated oils, only use A3/B4 rated oils and then preferably with the most recent ACEA rating. Personally I look for MB229.5 oils as a start point, then perform a calculation to determine the shear stability of the oil (calculate the kinematic viscosity at 150°C, multiply by density at 150°C to get dynamic viscosity, and see how much higher it is than the HTHS viscosity.) I've found an oil which doesn't have any shear, but so far I can't find it anywhere locally

I also like poyol esters, but there might be 200+ different kinds. Hence redline recommendation for petrols, because of the very strong add pack in a extremely stable base oil.
Thanks for your input Cuore_Sportivo_155 and JOHN156VELOCE, I've copied your replies into this thread.
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Thanks Jon, yeah its looking like many are already opting to change there oil before the manufacturers recommendation, as you say it makes the car look better on paper.

So this one Cuore_Sportivo_155 ?
Red Line Synthetic Oil - Motor Oil - 5W40 Motor Oil

there's a 10w40 too but it doesn't mention the MB229.5...
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Thanks for your input Cuore_Sportivo_155 and JOHN156VELOCE, I've copied your replies into this thread.
hey JBSmith, Cuore_Sportivo_155 and JOHN156VELOCE, I have posted on other forum with the oil grades topic some additional information and questions

regards, Preddy
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Who's side is your oil on?

We all know the drill, we look for oil stating the correct viscosity and key quotes like "high performance" and "advanced blend", "meets all ACEA requirements", "long-life" (you know, all the buzz marketing words used to sell) so all details sound perfect and I'm sure many would be thinking great! ticks all the box's! in she goes!

But are we actually buying a blend biased to meet regulations and emissions targets and trying to be an all round good fellow oil but has actually been forced to take the route of a higher percentage of detergent additives, and thus goes against exactly what us "severe service" people actually need.

Jon156Veloce made a good point, I wonder how many cars these manufacturers would sell if they had to say "you have to change your oil every 3k miles sir with this model"...hmm yeah, well this brings us back to the oil companies just giving the manufacturers an oil to meet regulations and achieve the 20k service!
But, what about us people who don't mind changing our oil as often as is required, is there a "better" suited blend for us?

So if we are not interested in an oil lasting 20k miles full of detergent additives to achieve this to the detriment of the anti-ware pack, I think we can move away from those "mainstream" bottles of oil and home in on a more specific blend may be more a "halfway oil" but not full "race" oil as we still need a percentage of those detergents.

The net is closing in on a more suited oil, as long as we understand that frequent oil changes will be mandatory e.g every 5k miles and from what I see that's not a problem with everyone, what will be interesting to see is how much this will extend the life of these timing systems, I hope it will be quite surprising.

Cuore_Sportivo_155 has gone to great trouble to explain his own findings and what to look for in the oil blend. I'm very interested in this Redline product range, and there will be other's found I'm sure.

Just another puzzle piece in the jigsaw just clicked into place I feel.
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Who's side is your oil on?

We all know the drill, we look for oil stating the correct viscosity and key quotes like "high performance" and "advanced blend", "meets all ACEA requirements", "long-life" (you know, all the buzz marketing words used to sell) so all details sound perfect and I'm sure many would be thinking great! ticks all the box's! in she goes!

But are we actually buying a blend biased to meet regulations and emissions targets and trying to be an all round good fellow oil but has actually been forced to take the route of a higher percentage of detergent additives, and thus goes against exactly what us "severe service" people actually need.

Jon156Veloce made a good point, I wonder how many cars these manufacturers would sell if they had to say "you have to change your oil every 3k miles sir with this model"...hmm yeah, well this brings us back to the oil companies just giving the manufacturers an oil to meet regulations and achieve the 20k service!
But, what about us people who don't mind changing our oil as often as is required, is there a "better" suited blend for us?

So if we are not interested in an oil lasting 20k miles full of detergent additives to achieve this to the detriment of the anti-ware pack, I think we can move away from those "mainstream" bottles of oil and home in on a more specific blend may be more a "halfway oil" but not full "race" oil as we still need a percentage of those detergents.

The net is closing in on a more suited oil, as long as we understand that frequent oil changes will be mandatory e.g every 5k miles and from what I see that's not a problem with everyone, what will be interesting to see is how much this will extend the life of these timing systems, I hope it will be quite surprising.

Cuore_Sportivo_155 has gone to great trouble to explain his own findings and what to look for in the oil blend. I'm very interested in this Redline product range, and there will be other's found I'm sure.

Just another puzzle piece in the jigsaw just clicked into place I feel.
JB and all,
I'm not sure I would prefer hypothesis to actual fact. There are many valid comments being made and any number of them could prove to be correct. However, manufacturers are not going to recommend long interval oil changes if indeed it will result in engines expiring before they are out of warranty. And given that cars are doing over 100,000 before needing to have chains and tensioners replaced, it just doesn't seem to fit? I have just checked with Alfa for the cost of the oil pump and that I can only conclude is the two "Sprockets" for want of a better word, meaning the internals which sit inside the housing on the end of the crank. They quote a price of £292-48 p. Given Alfa's pricing policy, or lack of one, this seems like a service item. It is true, the pump is passing previously circulated oil, back into the galleries, via the filter and oil cooler. So in this regard, there is merit in an earlier observation it may seem like grinding paste to the oil pump. And thus require changing when indeed the chains, guides and tensioners are done.

But to define where the problem lies in the system, the oil pressure needs to be checked. The point to check this is at the entry to the block, after the oil filter and cooler, where the current oil pressure switch is;quoted as£139-80 p. Given I have not as yet had an indication that the pressure is low, I make the broad assumption, it is Ok~. But, still I'm not comfortable with this, which is why I shall be fitting a oil pressure gauge along side the pressure switch. That will establish whether or not the oil pump has deteriorated. On the assumption it is Ok~, and my engine has; it is believed, used the specified grade oil, fair wear and tear on the chains, guides and tensioners are not unreasonable at 100,000 miles.

Which leads one back to poor build quality of some engines. Although that tensioner which JB, used as an illustration of gasket failure, was not actually from an Alfa Engine, it clearly is a weak spot and should not be discounted.

These oils are used throughout the automotive industry so their should be some degree of confidence in them. But, just supposing there is an issue with them, it makes sense to eliminate all other factors first. And for me, it's the mechanical interfacing: pump, oil cooler, pressure release valve, guides and tensioners. Even to the extent checking the variable valve timing; the Voids inside the cam shaft advance/retard mechanism are large and are fed from the same galleries as the tensioners.

These Voids are capacious, and there are four of them! The more enthusiastic a motorist is;working the gearbox and throttle, could substantially lead to quite a reduction in gallery pressure, more so than with a more conservative driver. One has to bear in mind, each cam shaft Advance Void has to be filled, while the Retard Void is drained. And equally, the Retard Void has to be filled, whilst the Advance Void is drained. The timing on the cam shafts is continuous, but the "Duty Cycle" for this will be wholly dependent upon the style of driving adopted by the man in the drivers seat.

I'm more than a little suspicious, this is where the problem lies. It would be a good exercise to look at the pressure in the galleries and how they vary between the sporting driver and the "plodder" - for want of a better word. In this instance, there could be a case for permanent electric oil pressure supplementation.

But it is also true to say, if the cam shaft advance and retard were constant, then the upper timing chains would be starved. This however does not appear to be an issue, so no one, so far can be accused of being that boring a driver!
Kind Regards,
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Thanks Jon, yeah its looking like many are already opting to change there oil before the manufacturers recommendation, as you say it makes the car look better on paper.

So this one Cuore_Sportivo_155 ?
Red Line Synthetic Oil - Motor Oil - 5W40 Motor Oil

there's a 10w40 too but it doesn't mention the MB229.5...
MB229.5 is by definition 0w30, 5w30, 0w40 or 5w40.

https://bevo.mercedes-benz.com/bevolisten/229.5_en.html that's the official list of approved oils, so not the "suitable for" or "recommended for" or "meets or exceeds" marketing speak...

Redline isn't approved, approval is VERY expensive. I like the redline chemistry though... Wish the oil was more readily available.
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Wave Nothing to do with oil pressures

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Originally Posted by IAMBRERA View Post
It's still an excessive price, if you do an internet search for about half a hour you'll find out all about this engine, & the parts what are needed are all GM made & can be soursed for no where near £3,300.

Some GM parts suppliers in the US can send you the parts for 100's if not less, not 1,000's though (all the parts too ) the only difference is they come in GM part bags, not Alfa Romeo ones.

So do you have any engine symptoms so other owners know what to expect if theirs goes? I'm thinking no engine running problems & just an EML "check engine light" could be the sensors need a clean, or replacing.

Option 3 probably would be what i'd do, then sourse the parts from GM US and have the 48,000 mile one fixed for little expence whilst the engines out. Once it's fixed you have a spare engine or it could be sold to cover the price of the new engine
IAMBRERA,
I would like to apologize for my crass stupidity. Not only was it out of character, but it was unforgivable, given I have spent many years of my life in the Middle East. And that alone indicates I should have been more sensitive to what is going on. I can only repeat what I said in an earlier post;"We do incredibly stupid things when alcohol is involved". Please accept my sincere apologies for any offense I may have caused you.
Kind Regards,
Brian.
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JB and all,
I'm not sure I would prefer hypothesis to actual fact. There are many valid comments being made and any number of them could prove to be correct. However, manufacturers are not going to recommend long interval oil changes if indeed it will result in engines expiring before they are out of warranty. And given that cars are doing over 100,000 before needing to have chains and tensioners replaced, it just doesn't seem to fit? I have just checked with Alfa for the cost of the oil pump and that I can only conclude is the two "Sprockets" for want of a better word, meaning the internals which sit inside the housing on the end of the crank. They quote a price of £292-48 p. Given Alfa's pricing policy, or lack of one, this seems like a service item. It is true, the pump is passing previously circulated oil, back into the galleries, via the filter and oil cooler. So in this regard, there is merit in an earlier observation it may seem like grinding paste to the oil pump. And thus require changing when indeed the chains, guides and tensioners are done.

But to define where the problem lies in the system, the oil pressure needs to be checked. The point to check this is at the entry to the block, after the oil filter and cooler, where the current oil pressure switch is;quoted as£139-80 p. Given I have not as yet had an indication that the pressure is low, I make the broad assumption, it is Ok~. But, still I'm not comfortable with this, which is why I shall be fitting a oil pressure gauge along side the pressure switch. That will establish whether or not the oil pump has deteriorated. On the assumption it is Ok~, and my engine has; it is believed, used the specified grade oil, fair wear and tear on the chains, guides and tensioners are not unreasonable at 100,000 miles.

Which leads one back to poor build quality of some engines. Although that tensioner which JB, used as an illustration of gasket failure, was not actually from an Alfa Engine, it clearly is a weak spot and should not be discounted.

These oils are used throughout the automotive industry so their should be some degree of confidence in them. But, just supposing there is an issue with them, it makes sense to eliminate all other factors first. And for me, it's the mechanical interfacing: pump, oil cooler, pressure release valve, guides and tensioners. Even to the extent checking the variable valve timing; the Voids inside the cam shaft advance/retard mechanism are large and are fed from the same galleries as the tensioners.

These Voids are capacious, and there are four of them! The more enthusiastic a motorist is;working the gearbox and throttle, could substantially lead to quite a reduction in gallery pressure, more so than with a more conservative driver. One has to bear in mind, each cam shaft Advance Void has to be filled, while the Retard Void is drained. And equally, the Retard Void has to be filled, whilst the Advance Void is drained. The timing on the cam shafts is continuous, but the "Duty Cycle" for this will be wholly dependent upon the style of driving adopted by the man in the drivers seat.

I'm more than a little suspicious, this is where the problem lies. It would be a good exercise to look at the pressure in the galleries and how they vary between the sporting driver and the "plodder" - for want of a better word. In this instance, there could be a case for permanent electric oil pressure supplementation.

But it is also true to say, if the cam shaft advance and retard were constant, then the upper timing chains would be starved. This however does not appear to be an issue, so no one, so far can be accused of being that boring a driver!
Kind Regards,

It has always been a puzzle as to why, the Alfa Romeo 3.2 Brera an 159 Engine has never met its stated consumption figures. It is only when one examines the “E-learn Disc” which was kindly given to me by a friend, it starts to appear obvious.
The 3.2 engine is a variant of the GM-Holden; modified, as is the usual practice of Alfa Romeo. In doing so, they try to maintain the myth that has sprung up around this once great company. I believe Henry Royce said, “Take the best design and make it better”. Thus initially Rolls Royce used American V8 engines. That Alfa can produce performance*engines on a shoestring*for mass production is a myth and can never be achieved by*“Tinkering around the edges”.
So why do I believe Alfa got this wrong and in what area(s)?

Variable valve Timing.

Anecdotally it is said the V.V.T. sensing is taken from all four cam shafts. Whilst I believe this is probably true of performance car manufacturers such as Ferrari, Lamborghini and Porsche, I do not think this is the case with the 3.2l Alfa engine. To do so would require a much more sophisticated E.C.U. as sampling rates would need to be four times faster and the potential for timing errors would increase dramatically. It would require a much faster E.C.U. program and to take advantage of this the sensor signals, would also need to be proportionally increased. This; the author believes, would be too expensive for what essentially is a mass production unit and disastrous with respect to vehicle warranties. So the preposition of this thesis is that timing signals are taken from a single cam shaft, notably one Inlet Cam shaft.
Given there are three detonations per revolution of the engine this would seem reasonable as it is the load on the engine, which dictates the advance or retard of the timing. This in itself being dependent upon throttle, cruise control and terrain. Plus, there is “Anti-Knock” sensing; common to the engine as a whole, which ensures camshaft advance is never so extreme as to cause continuous pre-detonation.

The load on any one cylinder is immediately reflected by a changing rate of pulses on the one cam shaft that is determining the advance/retard of the cam shafts, given they are linked by the timing chains.







Oil Pressure.

“To minimize engine wear and maintain specific power output it is implicit that oil pressure is maintained universally around the engine and that the pressure is constant at all points in the engine”.
Whilst it is true various components; depending upon their load characteristics, can operate at different pressures with respect to one another, it is however of paramount importance that all similar devices share a common oil pressure.
In this regard, we can specify the oil pressure to each cam shaft advance/retard mechanism. Clearly from the diagram below, this is not the case. The degree of advance/retard is dictated by the E.C.U, but the rate of advance is specific to the rate of “Fill” of the cam shaft voids and by definition “Oil Pressure”. Whatever bank inlet cam shaft is responsible for the timing: it is thought to be the left, the “Fill” rate for the left will be different than the right. Assuming it is the left hand bank inlet cam shaft, when the E.C.U. is satisfied with the advance/retard and the V.V.T. is “Set”, the right hand bank cam shafts; in terms of advance/retard, is not going to correlate with the left.
This error will amount to a loss of specific power output and consequentially, is detrimental to fuel economy. The data provided by Alfa Romeo states the extra urban economy is 33 MPG. I personally average 25 MPG. This is a whopping loss of 24% It seems impossible to improve on this figure on long journeys, no matter how the car is driven. Both advance and retard are determined by oil pressure and thus there is an innate timing error as a consequence of the unbalanced oil pressure in the supply galleries. This alone could account for some considerable loss in economy.
Fundamentally, the oil pressure for the left bank is derived from a “Tributary Gallery”, whilst that of the right hand bank is from the “Arterial Gallery”

Arterial Gallery.

The arterial gallery clearly supplies the crank shaft and journal bearings as well as the right hand bank cylinder head. The demand for oil by these components is considerable and place the greatest demand upon the oil pump. Essentially the entire left hand bank has an oil supply no greater than that of one of the oil ways for right hand bank's advance/retard mechanism!!!






It Gets Worse!

Lower Timing Chain Tensioner.

From the above drawing, it it is clear a fixed guide is attached to the Oil Pressure Pump, item 3. Item 2b is the lower timing chain fixed upper guide. However, the Item denoted by 1a and 1b is the Lower Timing Chain Hydraulic Tensioner.

The oil pressure for this tensioner is derived from the Left Hand Bank's Tributary Gallery!!!!

It should not therefore come as a surprise, the consequences of these fundamental engineering failings, results in lower timing chain stretch, guide and tensioner wear, due to oil starvation. Demand for oil by the lower timing chain tensioner further exacerbates V.V.T. errors, the consequences of which are lower economy than that as stated by the manufacturer and poor acceleration.
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It has always been a puzzle as to why, the Alfa Romeo 3.2 Brera an 159 Engine has never met its stated consumption figures. It is only when one examines the “E-learn Disc” which was kindly given to me by a friend, it starts to appear obvious.
The 3.2 engine is a variant of the GM-Holden; modified, as is the usual practice of Alfa Romeo. In doing so, they try to maintain the myth that has sprung up around this once great company. I believe Henry Royce said, “Take the best design and make it better”. Thus initially Rolls Royce used American V8 engines. That Alfa can produce performance*engines on a shoestring*for mass production is a myth and can never be achieved by*“Tinkering around the edges”.
So why do I believe Alfa got this wrong and in what area(s)?

Variable valve Timing.

Anecdotally it is said the V.V.T. sensing is taken from all four cam shafts. Whilst I believe this is probably true of performance car manufacturers such as Ferrari, Lamborghini and Porsche, I do not think this is the case with the 3.2l Alfa engine. To do so would require a much more sophisticated E.C.U. as sampling rates would need to be four times faster and the potential for timing errors would increase dramatically. It would require a much faster E.C.U. program and to take advantage of this the sensor signals, would also need to be proportionally increased. This; the author believes, would be too expensive for what essentially is a mass production unit and disastrous with respect to vehicle warranties. So the preposition of this thesis is that timing signals are taken from a single cam shaft, notably one Inlet Cam shaft.
Given there are three detonations per revolution of the engine this would seem reasonable as it is the load on the engine, which dictates the advance or retard of the timing. This in itself being dependent upon throttle, cruise control and terrain. Plus, there is “Anti-Knock” sensing; common to the engine as a whole, which ensures camshaft advance is never so extreme as to cause continuous pre-detonation.

The load on any one cylinder is immediately reflected by a changing rate of pulses on the one cam shaft that is determining the advance/retard of the cam shafts, given they are linked by the timing chains.







Oil Pressure.

“To minimize engine wear and maintain specific power output it is implicit that oil pressure is maintained universally around the engine and that the pressure is constant at all points in the engine”.
Whilst it is true various components; depending upon their load characteristics, can operate at different pressures with respect to one another, it is however of paramount importance that all similar devices share a common oil pressure.
In this regard, we can specify the oil pressure to each cam shaft advance/retard mechanism. Clearly from the diagram below, this is not the case. The degree of advance/retard is dictated by the E.C.U, but the rate of advance is specific to the rate of “Fill” of the cam shaft voids and by definition “Oil Pressure”. Whatever bank inlet cam shaft is responsible for the timing: it is thought to be the left, the “Fill” rate for the left will be different than the right. Assuming it is the left hand bank inlet cam shaft, when the E.C.U. is satisfied with the advance/retard and the V.V.T. is “Set”, the right hand bank cam shafts; in terms of advance/retard, is not going to correlate with the left.
This error will amount to a loss of specific power output and consequentially, is detrimental to fuel economy. The data provided by Alfa Romeo states the extra urban economy is 33 MPG. I personally average 25 MPG. This is a whopping loss of 24% It seems impossible to improve on this figure on long journeys, no matter how the car is driven. Both advance and retard are determined by oil pressure and thus there is an innate timing error as a consequence of the unbalanced oil pressure in the supply galleries. This alone could account for some considerable loss in economy.
Fundamentally, the oil pressure for the left bank is derived from a “Tributary Gallery”, whilst that of the right hand bank is from the “Arterial Gallery”

Arterial Gallery.

The arterial gallery clearly supplies the crank shaft and journal bearings as well as the right hand bank cylinder head. The demand for oil by these components is considerable and place the greatest demand upon the oil pump. Essentially the entire left hand bank has an oil supply no greater than that of one of the oil ways for right hand bank's advance/retard mechanism!!!






It Gets Worse!

Lower Timing Chain Tensioner.

From the above drawing, it it is clear a fixed guide is attached to the Oil Pressure Pump, item 3. Item 2b is the lower timing chain fixed upper guide. However, the Item denoted by 1a and 1b is the Lower Timing Chain Hydraulic Tensioner.

The oil pressure for this tensioner is derived from the Left Hand Bank's Tributary Gallery!!!!

It should not therefore come as a surprise, the consequences of these fundamental engineering failings, results in lower timing chain stretch, guide and tensioner wear, due to oil starvation. Demand for oil by the lower timing chain tensioner further exacerbates V.V.T. errors, the consequences of which are lower economy than that as stated by the manufacturer and poor acceleration.
Further investigations show that my original intention to feed the cam shaft advance is going to require a lot of work. In this I mean, the whole of the front has to be opened up and bulk head feed-throughs have to be fitted to feed the camshaft voids. This is going to take some time and money. And I want to go on holiday to Italy again this year. But crucially, so does my wife!!!. So my original plan plan is held in abeyance. But I also want to take the 159; but not at 25 MPG.

I am convinced it ought to meet at the very least the figures Alfa quote for extra urban, which is 33 MPG.
So as a stop gap, the least intrusive modification which should reap rewards is:-

1. Remove the oil pressure switch from the output of the oil cooler/input to the block.
2. Fit "T" piece and restore oil pressure switch.
3. Feed 8 mm. stainless pipe from the "T" piece to a non return/check valve.
4. Take output of N.R.V. to the left hand bank plug on the block; just below the cylinder head, having
removed the plug first.
5. A "T" piece can be fitted there for an auxiliary electric oil pump at a later stage.

On cold starts, the oil flow inertia will be reduced by 50% and the timing chain tensioner will be fed directly from the oil pump: less this supplementary line's inertia to flow. It is however, 8 mm. [ 6 mm. ID ], so there will be a considerable improvement.
Oil pressures around the block/heads, does not change. But the distribution is more balanced; the main crank and journals being fed from left and right and oil flow inertia considerably lower. The oil pressure imbalance to the V.V.T., between left bank and right is considerably reduced and I predict economy should as a result improve. And acceleration.

To achieve this is considerably less time consuming and thus less expensive. It is intended to use a supplementary oil pump eventually, which will essentially feed the right bank only - the central crank/journals being the only common point between the mechanical pump and the electric one. The electric one however, will support the whole block oil pressure at tick-over/low revs/pre-oiling on start-up. I have omitted a lot for sake of brevity, but will include in later posts. But for the time being, all that is required is one "T" piece/ banjo at the oil pressure switch, a non return valve, a 8 mm. feed into the left hand bank blanking plug and a length of 8 mm. stainless tubing to take it across the front of the engine; right to left.
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That all sounds plausible except that the oil pressure valve will ensure the correct and constant pressure to the individual component demand - the delay in oil pressure valve operation is much less than the demands of the VVT
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I am convinced it ought to meet at the very least the figures Alfa quote for extra urban, which is 33 MPG
I've had 31.8mpg average on a 200 mile run driving like a saint - which is probably not far off the extra urban test so figures seem reasonable
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That all sounds plausible except that the oil pressure valve will ensure the correct and constant pressure to the individual component demand - the delay in oil pressure valve operation is much less than the demands of the VVT
Not so, It does not take into account oil flow inertia. If you theory were correct, it would reduce losses universally across the power generation industry. In the perfect case, only fifty percent energy can be expended in any load, the rest is absorbed by natural losses in generating energy in the first place. And this is assuming no transmission losses, which can be translated as "System Inertia". It is true, the Oil pressure relief valve will blow at a predetermined level. But that is at the input to the system and not the output. between the two is the "System Inertia".
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I've had 31.8mpg average on a 200 mile run driving like a saint - which is probably not far off the extra urban test so figures seem reasonable
Well there you go. I'm impressed. So I was right all along, Alfa are world leaders in engine design. If only that were true.
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Well there you go. I'm impressed. So I was right all along, Alfa are world leaders in engine design. If only that were true.
GM built its own 3.2 L version of the engine in Australia. This version produced 227 bhp & 219 lb·ft torque with fuel economy of 12mpg urban, 21mpg extra urban (before Suzuki eventually added VVT to improve fuel economy).
Compared to the Alfa tweaked values of 260 bhp & 238 lb·ft torque with fuel economy of 17.8mpg urban, 33.2mpg extra urban I'd suggest that Alfa had a pretty good idea of how to improve the engine design (by adding direct injection and using the VVT)
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[QUOTE=no grip;14154225]GM built its own 3.2 L version of the engine in Australia. This version produced 227 bhp & 219 lb·ft torque with fuel economy of 12mpg urban, 21mpg extra urban (before Suzuki eventually added VVT to improve fuel economy).
Compared to the Alfa tweaked values of 260 bhp & 238 lb·ft torque with fuel economy of 17.8mpg urban, 33.2mpg extra urban I'd suggest that Alfa had a pretty good idea of how to improve the engine design (by adding direct injection and using the VVT

The fundamental question initially was, "Timing chain failure, guide and tensioner wear". Mine had to be changed at 100,000 miles. The car in question has problems at 48,000 miles. Even at 100,000 miles it falls short of what someone said on this site of a life expectancy of 150,000 miles. Researching this issue has led to a considerable weight of evidence pointing towards issues regarding V.V.T. and Oil Pressure. If it is not important to have "Oil Pressure Feed" balanced at all camshaft advance/retard mechanisms, then it is the same as saying, camshaft advance/retard has no bearing upon specific power output and thus acceleration and economy.
If as I believe, the V.V.T. sensing is taken from the left hand bank and its feed oil is taken from a gallery 1/4 the size of that that which feeds the right hand bank's V.V.T., the rate of fill is much slower. Yet it is the left hand bank which I believe feeds the E.C.U. with timing pulses. So if the left had bank voids are slower to fill, before the E.C.U. " Cam shaft Set" is issued, the right hand bank voids will have filled beyond the optimum position. If it has gone so far past when advancing, pre-detonation can occur. If this does happen, then the "Anti-knock" sensor will invoke the E.C.U. to retard the timing. So all in all the timing can be anywhere, depending on oil grade, oil temperature, engine load (foot on throttle), engine wear ( main bearing and journal wear) oil pump pressure and oil pressure relief valve spring tension.
There are so many factors involved. But this is the one that is most glaringly obvious. And from it falls the bulk of so many other issues, not least timing chain stretch.
The drilling for the left hand bank gallery appears to be about a quarter of the cross sectional area of the right bank from the oil cooler/pressure switch input. It was probably intentional as there must have been some concern about alignment of the two and potentially going through the walls in to the water jacket. Just a suspicion. But if the pictorial representation of the block's oil galleries on the E-learn disc are to be believed, it amounts to crass engineering stupidity. And feeding oil to the Lower Timing Chain Tensioner from the same gallery beggars belief!
So the fact that Alfa got 260 BHP, by "DIN Testing" suggests to me, this engine is capable of more. "DIN" testing an engine can hardly be called a simulation of how you and I drive the car, And if someone has to drive like my granny to get 31 miles to the gallon does not impress. The figure is "Extra Urban", not constantly sitting at 70 mph whilst reading "War and Peace".
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Each VVT actuator has a separate solenoid control valve which is actuated by the ECU based on information from lots of engine sensors. The oil pressure for each VVT is set independently from the ECU mapping. The size of the feed aperture is probably an issues if you're working in to 20k+ rev range but for our lumps where 7k is ambitious I doubt it will have a noticeable effect.
Nobody ever suggested that real world fuel figures are an accurate representation of how we drive. I only managed 31.8mpg once but it was a challenge.
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Each VVT actuator has a separate solenoid control valve which is actuated by the ECU based on information from lots of engine sensors. The oil pressure for each VVT is set independently from the ECU mapping. The size of the feed aperture is probably an issues if you're working in to 20k+ rev range but for our lumps where 7k is ambitious I doubt it will have a noticeable effect.
Nobody ever suggested that real world fuel figures are an accurate representation of how we drive. I only managed 31.8mpg once but it was a challenge.
Yes, each camshaft does have it's own solenoid which either opens the advance void, whilst draining the retard, or vice versa,or locks the cam shaft position, where the oil fill is sustained at the position the E.C.U. determined the solenoid valve should close. These should operate simultaneously on the instruction from the E.C.U. But the timing for this instruction is derived from a single cam shaft and not from all four as I understand it. Nowhere have I found any information to say there is more than two sensors on the crank shaft and one; believed to be, on the left hand bank inlet cam shaft.

The E.C.U. does not know where the cam shaft actually is within the voids. This a presumption based on the E.C.U. memory/program, based on the expected fill rate for the voids; a function of oil balance. The only time it knows where the camshafts are is when they are "Locked", when the engine is switched off or at "Tick-over" After that It does not care as once the correct advance/retard setting has been "assumed", by the one camshaft; from which the sensing is taken, they are all "set, supposedly at the position determined by this one cam shaft", safe in the knowledge that the fill rate for all four cam shafts is uniform.

It is my contention to have all for cam shafts sensed in a similar fashion is a luxury for the exotic end of the marked and not a bog standard GM lump such as this. And why would you want it? The only thing that would fail to make the camshaft advance/retard correlate, is not oil viscosity or oil pressure in itself, but unequal oil feed/pressure. That will occur as the left hand bank has a gallery 1/4 the cross sectional area of the right. The right has two tributaries feeding the camshafts, which are the same diameter as the left hand bank's main gallery. And then two galleries are fed from the left hand bank's main "narrow" gallery. And then the Lower Timing Chain Tensioner is fed from it too. And the timing chain tensioner has a valve on it's front face, which sprays the lower timing chain to lubricate it.

In my long career, I have for so many times emphasized the need to prove, not that something is correct. But something is incorrect. If one gets the same results after testing a least ten times from differing stand points, it suggests there may a valid argument for further investigation. To simply prevaricate achieves nothing. Real time testing, where a single issue is addressed to eliminate, or otherwise a single factor is the only means of determining whether it has any bearing on the symptoms being investigated. Each factor must be eliminated by testing whilst all other variables remain unchanged. For me, it is glaringly obvious. The disparity is so skewed, it cannot fail to have a bearing on engine performance and for that matter, timing chain stretch.

Let us presuppose, we use too thick an oil. The inertia this would cause would be universal. So a greater inertia in the V.V.T galleries would lead to an increase in main gallery pressure, from which the timing chain tensioner derives its oil, helping maintain timing chain tension. Acceleration would be slower; because of camshaft advance/delay hysteresis. Consequently, less load on the crankshaft and thus less load on the timing chain tensioner. So a thicker oil may indeed help reduce wear on the tensioners and guides, reduce slap on the chains, and further protect the vulnerable tensioners and guides due to power build up being delayed as a function of sluggish oil in the cam shaft voids.
And Main bearings and journals also benefit from increased viscosity.

Conversely, thin oil will do the opposite. But Galleries which do not have the same flow rates, will cause a problem, regardless of which oil one chooses.

Also, even if their were timing pulses derived from all four camshafts; which I don't believe there are, detonations are only 120 degrees apart and errors in camshaft advance/retard timing will still lead to my original preposition. Thinking about it, there can only be one camshaft from which timing pulses are taken. Otherwise the E.C.U. program would as I stated earlier, need to be four times as fast. The engine maps would have to be much more comprehensive for every camshaft position and the clock pulses increased proportionally to process the data from all four cam shaft pulses.

No, in my view, the only error introduced into the timing of this engine is due to unequal oil flow rates due to gallery restriction on the left bank. And timing chain stretch and tensioner wear is also indicative of this fundamental engineering flaw.
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