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Discussion Starter #1
I have now completed ~ 300 miles since the car has been back on the road. Before I detail any perceived changes in performance, I shall recap on the modifications made. I do not know, and Alfa will not say, if there are any differences between the 3.2 JTS Engines in a Brera or a 159. However, the Brera engine now installed and has it's original fuel injection system fitted. But the ECU remains that of the original 159.

1. The original Brera Crankshaft was bent 23 - 24 thou "Out of Alignment" and it was suggested it could not be restored. However, Ivor Searle of Soham; near Cambridge, pulled the Crankshaft back to within a couple of thou such that it could be re - ground to first oversize Main Bearings and Con - Rod bearings. However, they told me they had to shave some metal off to get the "Wedges" in to start the process of alignment. Because of this, I felt it only right that the crankshaft should be checked for balance. So I supplied Scholar engines with my Con Rods and Pistons, a New Replacement Con Rod for the one which had spun (£200) and the New Crankshaft I purchased in anticipation of the original being beyond redemption, which they would use for reference. Scholar thus balanced all components, plus my Spare Crankshaft, which they said needed more taking off than the original. Even so, the amount shaved off all parts, to bring them into balance was minimal.

The Block was cleaned and all oil ways and galleries "Rod - ed", latest design "Spray Jets" fitted. These have slightly longer nozzles and their shape is more defined than the original.

The Block Orifice, where the oil leaving the Pump enters the Block was machined to produce a smoother radius for oil flow. This feed enters the Block and immediately turns through 90 deg. to exit once again and enter the "Oil Cooler/Filter Module". Improving the profile of this short section should reduce agitation of the oil which creates back - pressure on the Pump and its "Oil Pressure Relief Valve". Hopefully sustaining oil pressure better due to improved flow characteristics.

There were a couple of small "Nicks" on the top of the cylinder bores/block and it was suggested they are best removed to provide nicely machined surfaces for the head gaskets. So they were lightly skimmed, which will make a marginal improvement to the compression ratio.

The Closed Loop Lubrication System was fitted after the Oil Cooler/Filter Module was modified to take the extra pipework. This supplements the oil pressure to the Rear Bank, via the "Block Plug" nearest the "Lower Timing Chain Tensioner". A second feed from the Oil Cooler/Filter module is a "Horseshoe" 12 mm. pipe from the Cooler/Filter, directly into the "Front Bank Main Oil Gallery". The Oil Pressure Sensor/Switch is moved from its original position and "Tee - ed" into the Horseshoe.

The Sump was thoroughly cleaned and "Baffle Walls" welded to channel oil via the lower face of the "Oil Feed Pick - up Snout".

The Oil Pick - up Snout was lowered as it was felt sat too high and could result in air being drawn into the oil feed on cornering, even when oil levels were good.

Plates were welded to the walls of the Sump to carry the oil returning from the Cylinder Heads, to below the Windage Plate, to prevent it being dragged into "Windage" [ these drains are adjacent to the rotating journals and the returning oil flow rate, being not particularly great would easily be dragged into windage, thus delaying the return flow to the sump - a problem this engine is known to suffer from]

The "Windage Plate" was extended to cover the full length of the sump, some 25% of it hitherto left exposed.
 

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My goodness 300 miles already and this engine still alive? with 8 bar oil pressure at idle. Oh excuse me its 9 Bar according to a different post. 9 Bar you dont get at 6000rpms! thats 130 psi - 900Kpa..seriously, spins us another one brother.
 

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Discussion Starter #3
My goodness 300 miles already and this engine still alive? with 8 bar oil pressure at idle. Oh excuse me its 9 Bar according to a different post. 9 Bar you dont get at 6000rpms! thats 130 psi - 900Kpa..seriously, spins us another one brother.
" thats 130 psi - 900Kpa" - did you work that out all by yourself?

For your information the Spec for the 3.2 JTS - e-disc - states 4 to 6 bar oil pressure. I presume that is normal running pressure latitude. However, the garage which was trying to identify the issue with the hydraulic tappets discovered they could not get the oil pressure up and the heads were still dry. They did finally get oil pressure up on the starter motor and phoned me to say they were seeing 4 bar at the horseshoe loop. I believe I posted 3.5 bar. subsequently, when the issue of the tappets was resolved, they reported by telephone that she was running and they were seeing 9 bar with the engine at 750 rpm.. I probably posted 8 bar.

At that point I had not myself seen the figures they reported. However, if their test equipment is to be believed - and I do believe their kit to be good - sure enough the pressure at the horseshoe loop was indicating 9 bar. Now this is on an engine which has just been rebuilt with all new bearings, spray jets which operate at a higher pressure, new timing chains, tensioners, guides, overhauled VVT's and new oil pump. A major restriction at the outlet of the oil pump had been relieved and two major restrictions from the oil cooler/filter unit, into the block had been circumvented, aside from the new oil feed to the rear bank.

The oil, 5W40 was cold and it was commented that it would probably settle out at ~6 bar when fully warmed. I did however post that this was on an engine which had just been started, after the issue of the tappets was resolved.

Now, you don't appear to have a reputation for a Contrary ******, certainly I could do without any more. But I suppose, given time you could well prove to be a veritable PITA. Or alternatively, you could try and contribute positively - your choice!
 

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My goodness 300 miles already and this engine still alive? with 8 bar oil pressure at idle. Oh excuse me its 9 Bar according to a different post. 9 Bar you dont get at 6000rpms! thats 130 psi - 900Kpa..seriously, spins us another one brother.

This isn’t Twitter. Remember what your Mum said about what to do when you haven’t got anything nice to say....


Sent from my iPhone using Tapatalk
 

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But I can see his point....ideally, oil pressure should be between 25 to 65 psi when the oil is warm. A reading of 80 psi or higher usually means that there is a serious issue regarding flow or restriction that needs to be resolved. So 6 bar...about 90 PSI should not be exceeded........IMO of course!!! Many seals/gaskets will be on there design limit at that sort of pressure ....and I will admit that this closed loop system is a bit alien to me.
 

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Discussion Starter #6
But I can see his point....ideally, oil pressure should be between 25 to 65 psi when the oil is warm. A reading of 80 psi or higher usually means that there is a serious issue regarding flow or restriction that needs to be resolved. So 6 bar...about 90 PSI should not be exceeded........IMO of course!!! Many seals/gaskets will be on there design limit at that sort of pressure ....and I will admit that this closed loop system is a bit alien to me.
It is Alfa who quote 4 - 6 bar. The new oil pump is Alfa.

The oil in this engine does not just serve bearings. It seeks to provide for the dynamic response of the valve timing and timing chain tension as well. Not to mention the hydraulic tappets.

The speed the vvt’s operate at is wholly dependent upon oil pressure and that pressure can only be maintained if potential flow rate exceeds demand by a considerable margin.

And it is also important to understand, the timing chain tensioners, in the absence of oil pressure, have to rely on their internal springs, which are too weak to maintain tension.

True, there is a NRV in the tensioners. But they are between the hydraulic pistons and the engine oil feed.

There is no valve on the front face of the tensioner nylon guide.

So unless there is sufficient oil flow to maintain the pressure on the tensioner piston, when oil is bleeding through the front face onto the timing chain, the tensioner will be; and is, forced back into its cylinder and is reliant upon only its internal spring, which is inadequate.

By relieving the restrictions, the potential flow rate is now greater than actual flow rate demand. Thus pressure is higher. But the bypass valve in the oil pump has not changed!!!

Secondly, restrictions in the oil feeds, cause a back pressure on the oil pump relief valve, causing it to open further, at a lower flow rate than the engine demand requires. And because of this, oil pressure beyond any restriction drops.

This is a fundamental law of Hydraulics.

And to reiterate, the galleries, oil cooler/filter and pump are standard. Many performance engines, Aeronautical engines, marine engines employ the same techniques I have adopted.
 

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Discussion Starter #7
But I can see his point....ideally, oil pressure should be between 25 to 65 psi when the oil is warm. A reading of 80 psi or higher usually means that there is a serious issue regarding flow or restriction that needs to be resolved. So 6 bar...about 90 PSI should not be exceeded........IMO of course!!! Many seals/gaskets will be on there design limit at that sort of pressure ....and I will admit that this closed loop system is a bit alien to me.
“A reading of 80 psi or higher usually means that there is a serious issue regarding flow or restriction that needs to be resolved.

If one looks at the picture of the Brera block, with the CLLS fitted ( Modified 3.2 JTS rebuild thread), it is quite obvious the additional pipework actually reduces oil flow inertia between the output of the oil cooler/ filter module and both the input to the main gallery of the front bank, and supplements the oil flow to the rear bank, via the bypass line. So the oil feed for the rear bank comes from across the central (Vee) of the block - normal route - and the line to the lower timing chain tensioner.

My crankshaft has been reground and + 0.25 shells fitted. There are no seals within this engine; in the conventional sense as orifices in the Stainless steel head gaskets provide the prerequisite flow to the vvt’s, camshaft bearings and hydraulic tappets.

So it is difficult to envisage where exactly there would be any restrictions.

The orifices for the oil feeds to the tensioners are small, smaller by a considerable margin than those on the front faces, through which they lubricate the chains.
 

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This isn’t Twitter. Remember what your Mum said about what to do when you haven’t got anything nice to say....
Thank you for the suggestion.

With regard to fluid dynamics what has been presented in this thread and others is pure fallacy.

Basic fluid dynamics / flow continuity

930872



Flow in (1) = the sum of flow out (2) +(3) ..........now introduce an additional circuit
Flow in (1) = the sum of flow out (2) +(3) +(4)

Effectively the flow in the engine oil galleries has been reduced due to the addition of a circuit since the
source (oil pump) remains constant.

Your welcome
 

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Discussion Starter #9
Thank you for the suggestion.

With regard to fluid dynamics what has been presented in this thread and others is pure fallacy.

Basic fluid dynamics / flow continuity

View attachment 930872


Flow in (1) = the sum of flow out (2) +(3) ..........now introduce an additional circuit
Flow in (1) = the sum of flow out (2) +(3) +(4)

Effectively the flow in the engine oil galleries has been reduced due to the addition of a circuit since the
source (oil pump) remains constant.

Your welcome
But you are mis - representing what I am driving at. But your diagram helps make my point clearer.

Let’s say line (3), has been “pinched” between source and utility. Had that “pinch” not existed, let’s say the flow rate was equal to the demand of the utility. However, the flow rate beyond the pinch has reduced. If the original pipe was 1 cm. x - sectional area and the pinch effectively halved that x - section, flow rate would be 1/4 [constant pressure].

However, line (4) recombines with (3) beyond the “pinch” and it does so in a way that restores the flow potential to that of the original 1 cm. x - sectional area. Effectively negating the pinch in its entirety. And if (4) happens to create a combined x - sectional area of greater than 1 cm. flow rate inertia is reduced overall.

In the case of the horseshoe link, it combines with the front bank main gallery - fitted where once a blanking plug existed.

And the rear bypass line, fitted where the blanking plug nearest the lower timing chain tensioner once was, recombines with the rear bank main gallery.

The combined effect being to reduce the impact; eliminate more accurately, of the block restrictions and importantly, allows the oil pump oil pressure relief valve to act in a way that maintains pressure. Which is doubly important when the oil thins with temperature.

To complete your picture, there should be (5) which recombines with (2). (4) being the horseshoe and (5) being the rear bypass line.

The restrictive section of block at the outlet of the oil pump could not be circumvented, without a major engineering rework. So improving the profile of the bend was the best that could be done. However, by removing sharp machined edges, it also reduces the potential for air dissolved in the oil - resting time for the oil is too short (because of the small capacity sump) - from precipitating out of suspension and forming bubbles in the oil ways.

Another function of the spray jets, which are fed from the crankshaft main bearing gallery is to allow any entrained air - expanding because of the heat and pressure reduction - to be purged through the nozzles and not the main or con rod bearings.
 

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Discussion Starter #10
But you are mis - representing what I am driving at. But your diagram helps make my point clearer.

Let’s say line (3), has been “pinched” between source and utility. Had that “pinch” not existed, let’s say the flow rate was equal to the demand of the utility. However, the flow rate beyond the pinch has reduced. If the original pipe was 1 cm. diameter and the pinch effectively halved that diameter, flow rate would be 1/4 [constant pressure].

However, line (4) recombines with (3) beyond the “pinch” and it does so in a way that restores the flow potential to that of the original 1 cm. diameter Effectively negating the pinch in its entirety. And if (4) happens to create a combined x - sectional area of greater than that of a 1 cm. diameter pipe, flow rate inertia is reduced overall.

In the case of the horseshoe link, it combines with the front bank main gallery - fitted where once a blanking plug existed.

And the rear bypass line, fitted where the blanking plug nearest the lower timing chain tensioner once was, recombines with the rear bank main gallery.

The combined effect being to reduce the impact; eliminate more accurately, of the block restrictions and importantly, allows the oil pump oil pressure relief valve to act in a way that maintains pressure. Which is doubly important when the oil thins with temperature.

To complete your picture, there should be (5) which recombines with (2). (4) being the horseshoe and (5) being the rear bypass line.

The restrictive section of block at the outlet of the oil pump could not be circumvented, without a major engineering rework. So improving the profile of the bend was the best that could be done. However, by removing sharp machined edges, it also reduces the potential for air dissolved in the oil - resting time for the oil is too short (because of the small capacity sump) - from precipitating out of suspension and forming bubbles in the oil ways.

Another function of the spray jets, which are fed from the crankshaft main bearing gallery is to allow any entrained air - expanding because of the heat and pressure reduction - to be purged through the nozzles and not the main or con rod bearings.
 

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Discussion Starter #11
Happy to report that a problem, which scared the hell out of me has been resolved. Near side rear wheel bearing had failed and I could not identify what or where the racket was coming from. Initially thinking it may have something to do with transmission - prop shaft, half shafts, transfer box, etc.

However, wheel bearing it was and I pick the car up again tomorrow.
 

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Discussion Starter #12
Happy to report that a problem, which scared the hell out of me has been resolved. Near side rear wheel bearing had failed and I could not identify what or where the racket was coming from. Initially thinking it may have something to do with transmission - prop shaft, half shafts, transfer box, etc.

However, wheel bearing it was and I pick the car up again tomorrow.

Wheel bearing replaced and all good. Hope that is the end of issues for a little while. Still keeping an eye on the revs but sounding good. As was pointed out, I have been driving around in a GT diesel so I need to re - familiarize with a petrol V6, and a heavy one at that. Exhaust note more to do with me snatching a high gear too soon. Need to compare with my mates Brera.
 

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Discussion Starter #13
Happy to report that a problem, which scared the hell out of me has been resolved. Near side rear wheel bearing had failed and I could not identify what or where the racket was coming from. Initially thinking it may have something to do with transmission - prop shaft, half shafts, transfer box, etc.

However, wheel bearing it was and I pick the car up again tomorrow.
New Years Eve - hope you all had a good Xmas and good fortune comes your way in the New Year.

Still being gentle with the engine but now just on a hundred before a filter/oil change.

Engine really running cool - an hour and a half’s drive and the inlet plenum and front cam cover, hot to the hand, but not sufficient to withdraw it. Oil temp gauge still not moved from seventy deg. C.

Clatter from cylinder head (said to be high pressure injector noise) gone. Genuine sense of singer sewing machine/Hornby 00 engine; nice mechanical whirring, on tick over - sweet to the ear.

Not completely smooth when accelerating, almost as if it had Weber Carbs and progression/jets not quite balanced. Also oil level dropped a bit - topped up and seems fine, although I now have more confidence in the oil level display on the dash.

Revs creeping up, but chickening our at 4K. Seems to catch me out and doesn’t give me time to set the car up. But, it is definitely Busso like, albeit with a little more mechanical noise - chains and not belts.

Economy, nothing special ~ 27 - ish. But not really had a long run on good roads yet.

Bottom end torque much improved but can only confirm with a/b comparison with mates Brera and Dynamometer plot. Is it 300 bhp +. Well it’s not had it’s neck rung yet! I need to let the desire to build, before I go to Clive Atthowe.

Love it but, it is a bit of an ugly duckling performance wise. It may be better with an automatic box. Or it may just be me, not coming to terms with the difference.

The rear wheel bearing worked a treat and I will probably do the off side soon. And I am not sure I shouldn’t change the front ones as well, because I don’t think I can entirely blame the “P Zeros” for the sound track. They are however 40’s profile and should be 45’s. But a softer compound would help. Plus, they are bloody expensive. Great grip though - particularly in the wet.
 

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Happy Christmas and new year. Great to hear the engines running fine. Looking forward to how she drives once run in.
Since drilling my front Manifold cat through my oil temp rarely goes above 70 now. Thinking about getting those Mace insulators for the intake as. I can always fry an egg on mine
 

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Hopefully that's not the case...70C is only 158F (sorry I think in F not C!). That's too low to be healthy for your engine.
For a road car, engine oil needs to be at least 220 degrees F (about 105C) to burn off all the deposits and accumulated water vapour. For every pound of fuel burned in an engine, the combustion process also generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water’s boiling point), the water will mix with sulphur (another combustion by-product) and create acids that can eventually damage bearings.
Just something to think about.....
 

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HNY,Brian! What do you mean by ugly duckling performance wise?Is the 159 facelift? Why would it be better with auto? I am curious to hear her singing.
 

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Discussion Starter #17
Hopefully that's not the case...70C is only 158F (sorry I think in F not C!). That's too low to be healthy for your engine.
For a road car, engine oil needs to be at least 220 degrees F (about 105C) to burn off all the deposits and accumulated water vapour. For every pound of fuel burned in an engine, the combustion process also generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water’s boiling point), the water will mix with sulphur (another combustion by-product) and create acids that can eventually damage bearings.
Just something to think about.....
We can’t start retrospectively adding provisos which did not apply to the Busso’s, before they had manifold cats fitted. There no doubt truth in what you say, but it is not wholly the truth.

My take on the temperature indication is, it is taken from the sump and not a true indication of the oil temperature in circulation. That is something I will look into, when time permits.

However, temperature of the oil after the oil pump will be higher, and the heat exchanger is more like an oil preheater. The bearing temperatures oil galleries will however be higher, given the pressure and the sheer. So I believe it is fine. But we shall find out soon enough.

True, 1 lb of water per lb fuel, but that is in the combustion chamber, not the Crankcase or sump. There will be some as a consequence of blow by, but c/r is not fully exploited unless in WOT. However, it is important to ensure good Crankcase scavenging through the PCV system. And lastly, keep on top of oil and filter changes.
 

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Discussion Starter #18
HNY,Brian! What do you mean by ugly duckling performance wise?Is the 159 facelift? Why would it be better with auto? I am curious to hear her singing.
Hi Red.

One of the issues that became obvious to me when driving in my mates Q4 Brera, which is an auto, was the continuous hunting up and down of the box at low speeds. From the plots I supplied (a/b comparisons of his Brera and my post mod - ed 159), the most noticeable difference in performance was the bottom end torque of the Brera was dramatically worse than my 159’s.

So the Auto-box isn’t very happy. So I reasoned any improvement in torque at the bottom end would be a real bonus for an automatic.

However, the F40 in the 159, Q4 has triple cones on 1st and 2nd synchromeshes. And on mine, they will not be hurried. So, improving the torque at low speeds with the manual box doesn’t improve my driving technique. It seems to take three days to shift through them and I loose a lot of time. Maybe my technique will improve, but I think my GTV would be 30 yards ahead before I got moving off the line. The alternative is, a lot of wear on the clutch.

Although I have yet to confirm it, the bottom end torque seems to be even stronger now. So an auto box would probably suit the car better now. However, that ain’t going to happen so I better improve my technique.

Perhaps not an ugly duckling, but is not pretty pulling away enthusiastically. Gently and it seems very composed. And the exhaust note turns heads. But hitting the throttle from the off, only for speed to fall off as I seek second (OK not that slowly) because she is a heavy old girl, is a bit embarrassing. Made worse by virtue of the exhaust note dying in sympathy with momentum.
 

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Discussion Starter #19
Hopefully that's not the case...70C is only 158F (sorry I think in F not C!). That's too low to be healthy for your engine.
For a road car, engine oil needs to be at least 220 degrees F (about 105C) to burn off all the deposits and accumulated water vapour. For every pound of fuel burned in an engine, the combustion process also generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water’s boiling point), the water will mix with sulphur (another combustion by-product) and create acids that can eventually damage bearings.
Just something to think about.....
We can’t start retrospectively adding provisos which did not apply to the Busso’s, before they had manifold cats fitted. There no doubt truth in what you say, but it is not wholly the truth.

My take on the temperature indication is, it is taken from the sump and not a true indication of the oil temperature in circulation. That is something I will look into, when time permits.

However, temperature of the oil after the oil pump will be higher, although the heat exchanger cannot possibly in the bearings will however be higher, given the pressure and the sheer. So I believe it is fine. But we shall find out soon enough.

  • True, 1 lb of water per lb fuel, but that is in the combustion chamber, not the Crankcase or sump. There will be some as a consequence of blow by, but c/r is not fully exploited unless in WOT. However, it is important to ensure good Crankcase scavenging through the PCV system. And lastly, keep on top of oil and filter changes.
 
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