vr6 oil eater

[dr_mat 0]

No he means full LOAD, you don't achieve 100% cylinder pressure without putting the engine under load, so you're not going to blow past the piston rings otherwise ..

[Dutch24V 0]

no, sorry, what he said 8)

[kop10320178 0]

ok

i get it thanks

[Kevin Bacon 5]

BenM, good information! It doesn't surprise me either. It's quite ironic that the engineer you spoke to scathed the VR6 engine, and yet they continued with it! Seems the VR is here to stay!

 

I regularly speak to Vince at stealth racing about the VR engine and having worked on them for the best part of 10 years, he's theorised that the reason 1 and 6 wear out first is because they run the hottest due to the water jackets at each end of the block being approx half the size of the inner cylinders' jackets.

 

He's also seen poorly assembled blocks from VW too.

 

Still, it's a fabulous engine when working right.

[Kevin Bacon 5]

,i switched to a better oil which nearly halved oil consumption

 

So did I and got the same results. Over-run smoking and consumption have dramatically dropped since switching to Silkolene.

[HiAsAKite 0]

I get the odd puff of blue following an overrun- generally I use 1 litre anything between 500 and 1500 miles- depends on driving style...

 

Used virtually no oil going to Le Mans and back (pretty much constant 120kph all the way)...

....whilst cornwall and back will use loads (lots of hills and use of engine braking..)

[edd 0]

Interesting fact (if i remember my figures right!!) according to Vince 9 out of 10 vr's that have major engine work carried out on them at Stealth are rado 2.9's and the main reason being "the just run too damn hot!!"

[dr_mat 0]

He doesn't know the answer, that's pure speculation ..

[BenM 0]

I regularly speak to Vince at stealth racing about the VR engine and having worked on them for the best part of 10 years, he's theorised that the reason 1 and 6 wear out first is because they run the hottest due to the water jackets at each end of the block being approx half the size of the inner cylinders' jackets.

 

The end cylinders have a completely different distortion pattern to the centre ones, because they don't have the stiffness of another adjacent cylinder to support them. Therefore you tend to get a bulge at either end of the engine on 1 and 6 in the distortion pattern and hence accelerated wear.

 

The guy I spoke to was talking purely from a casting point of view. The VRs in the Corrados were fairly early in the engine development cycle, this sort of thing is usually designed out with external ribbing or a change in water jacket shape. Haven't seen an old or new VR block 'naked' so I don't know if or how they have been modified.

[ardandy 0]

Mines just started doing this.

 

Going down a long hill at 30 in 5th for about a mile. Go to the junction and when I set off I saw a cloud of blue smoke behind me. After that, it didn't do it, even when booting it stood still.

 

Is this something I should get checked out or 'standard for a 13yr olf VR'?

[Kevin Bacon 5]

Over run for that length of time will make all but the healthiest of VRs smoke when accelerating again.

 

Change to a thicker oil and it will more than likely cure it. I use Silkolene Pro S 10W/50 and the engine uses hardly anything at all now. I only check it once a month and it barely moves off max. Not bad for a 132K engine, although I did get the head rebuilt at 93,000....but it still smoked, LOL!

[ardandy 0]

I'm using silver synta (10w40???) vw stuff for the VR. Can I assume VW dont supply thicker stuff and silkolene's the way?

[Kevin Bacon 5]

That's exactly the stuff mine used to smoke on the over run with. Changed to Silky a year ago and it hasn't done it since.

 

VW won't sell any decent oil other than the watery thin 0W/30 they put in current cars.

 

Speak to Oilman, he sells the Silky, brilliant service. It's not cheap, but better than the humilitation of plumes of smoke pouring out of a 'reliable' VW :-)

[double-6s 0]

I win :)

 

Mine uses shed loads of oil all the time. I keep a large tub in the boot. And it oils up no.1 plug in a matter of hours if it fancies :)

 

Has pretty much stopped giving decent performance now as well - sometimes it still rocks, but not very often.

[Timo. 0]

I spent over a grand on a head rebuild after serious smoking and oil consumption.

 

I can still get it to smoke after long over-run although it barely uses any oil now.

 

I would hold onto your money and put up with it, unless its uses loads of oil.

 

T.

[peterh 0]

Mines using something like one litre every 1000miles for so at the moment. I assume the engine has done the 140k the clock is showing. The head was overhauled just before I got the C back a the beginning of march. Im confident its all leaking past the rings. Engine still pulls like hell mind you.

 

Ive also got wear on the syncro on 2nd gear. When the box gets hot after a long run I can easily beat the syncro and get a nasty crunch. The gearbox also takes ages to spin down when hot, meaning you have to hold the clutch down for rather a long time else you get a crunch when shifting to reverse. Im guessing this is just due to low friction in the box due to worn seals and bearings.

 

Thinking of overhauling the box this summer and possiblly wipping the head and sump off and honing out the bores and re-ringging. Anyone had much success at reducing oil consumption with a hone and re-ring?

[ardandy 0]

Jusy had a word with a very good trusted mechanic and he said that he can't see the silkolene oil being any different. Its just thicker at higher temps (I might have got that wrong way round)?

 

He did say its worth a try come next oil change but its prob just the rings its getting past.

 

'Wait until it gets worse' was his advise, unless you have spare cash!

[Kevin Bacon 5]

Anyone had much success at reducing oil consumption with a hone and re-ring?

 

I don't think that will help as bores 1 and 6 ovalise. Needs boring out to 2897cc with Mahle 82.5mm pistons I'm afraid.

 

It costs about £3k to fully rebuild a 12v VR engine professionally, which is why eventually there will be a big queue outside Stealth and PSI Tuning for 24V conversions.....although it's still early days as yet to tell if the 24V engine's block has been improved to prevent ovalisation. I suspect the 24V block might have ribbing around cylinders 1 and 6 on the block to strengthen it....need to look at one close up I think.

 

Ardandy, it's not just the thickness, but also the quality of the oil. As I say, using it my engine has reduced consumption significantly.

[peterh 0]

Well surely the block was bored by VW at manufacture to have round bores on cylinders 1 & 6. They only become oval when hot and under stress, so surely the ovalness can only account for the recommended oil consumpsion? Also bores wear during use right? and generally the engine is at running temperature, so over engine hours would the bore not be worn to a corrected shape which at operating temperatures would be rounder than on a new engine? Surely there would be greater wear on the thinner part of the oval by the piston rings, and on the larger part of the oval?

 

My point is that if my oil comsumption is worse than a new run-in engine then surely either honing to remove glazing, or as you point out a rebore, would take me back to the better oil consumption?

[Kevin Bacon 5]

Well of course it was?! I meant bores 1 and 6 wear out prematurely compared to 2, 3, 4 & 5 and stay oval permanently.

 

No engine's bores are perfectly round once the head has been clamped down, but the problems with the VR block in particular are, bores 1 and 6 A) have the smallest cooling jackets, and B) is where the block is thinnest and there are no strengthening ribs to compensate. So when the heads were clamped down at the factory, a lot of engines had bulging blocks and weren't onto a good start from day one.

 

And also with all engines, you get good Monday morning ones, and you get bad Friday afternoon jobs.

 

In short, your bores are worn and need reboring.

[rixy 0]

think i've got the same problem, need mine doing too, but mine is already a 2.9 C engine, what is best to do, get a 2.8 block and re bore to 2.9, or re bore my existing lump to a overbore or 3.1 etc? What approximate costs could i incurr if i do all the rebuild work myself,and just get the CNC work done professionally? How much are new overbore or 3.1 pistons/rings?

[Timo. 0]

rixy, So many questions.

 

Whats your's doing, using loads of oil?? Does it smoke on hard acceleration or just after long over-run?

 

getting a 2.8 lump re bored is often a good route. To be honest you're almost better buying a second hand lump.

 

It'll be much cheaper doing it yourself, but the parts are still around 4-500 pound mark.

 

T.

[ardandy 0]

OK, mines doing the overrun thing now after 0.2-0.3 miles of overrun. Does this seem excessive?

[Roger Blassberg 0]

Try http://www.oemparts.co.uk. They do a full 2.9 ABV engine for £2185 incl. VAT and delivery. It's alot of money, but compared to a head and chains job it's damned cheap.

 

Has anyone used this supplier??

 

Best wishes

 

RB

[ardandy 0]

Isn't a full engine rebuild & rebore £2300?

 

I'm assuming their engine is rebuilt?