No, not mine!!!! A guy I work with has a mk2 16v with a rebuilt lightened/balanced ABF bottom end, flowed head/manifolds, copy Schrick 268/276 cams etc etc He recently took the car to Stealth & had it RR'd but it only made 156BHP/133lbs/ft [:^(] Shockingly poor IMO.! I reckon it is at least 20BHP down.. Vince told him he couldnt put any ignition advance on whatsoever as pinked its head off, so the ignition timing is now well retarded, even from standard, hence the low power.... Has anyone got any ideas as to why this could be happening? The engine was built by a reputable company so the C.R shouldnt be too high, Compressions were 180/180/160/130...so too low on 2 cylinders if anything Head hasnt had a massive skim & block hasnt been decked Could cam timing affect ignition timing if set up wrong, given the dizzy runs off the exhaust cam?? The power curve itself was smooth, & fuelling bang on (WUR mod done)....just a bit lame power wise.... Anyone got any ideas? Edited by: chrismc
I'd be looking into that cylinder with 130, there shouldn't be that much variance between the cylinders.
He realises that the compressions are also a problem, but cant understand why it pinks so much even with retarded timing..
I think Vince was a bit stumped from what I can gather... Suggested sticking KR cams back in but I cant see how that would affect Pinking Edited by: chrismc
i had the same problem on my 2l with the old digi head, couldnt put anywhere near the std 6deg advance, was more like 0deg, but aparently that was due to the poor digi ignition map, i assume he's using the k-jet setup and not mk3 digi setup?
Sounds familiar Has the engine got any other issues such as overheating? Wondering if it's got a headgasket weeping (on the 130 cylinder) That will make it pink. Edited by: GVK
Come to think of it. It may not be relevent, but one day i remember chatting to him at work. He was in his car with the engine runing and what seemed like not very long the fan cut in and out a couple of times. Could that be a factor Gary...
Could be Nick, I'd be having a look deeper to find out why it's got the low compression, surely it's got to be something to do with the pinking as well.
Remember I had the exact same problem, and it turned out to be the ECU. Couldnt run anywhere near standard advance because it pinked so much.... EDIT: remember if he's running loads of retard on the ignition its going to run a lot hotter as well. Edited by: smithy
Good point Smithy it could well be that causing the pinking, but that doesn't account for the 130psi comp on one cylinder.
Yeah, there must be something up with that cylinder right enough GVK, certainly wont be helping power...
just a thought, How old many miles has the engine done since the rebuild? I've just come back from Stealth after putting K-Jet back on and could only go 3degrees before it pinks- Vince thinks the reason why is because my head is probably coked up to @^* from having run carbs for a couple years... the fuel pops off the red hot carbon before the spark. So could be that causing or supporting othersymptonsto the ignition problem???
No..the head shouldnt be coked up as its all just been rebuilt/flowed etc etc..(about 10K ago) Vince did ask him if the engine was from a breakers (thinking cokeing could be the problem)
Thoughts- - Copy shricks? by who? so could be any old profiles then? Silver rocco- about bang on whats to be expected @ Stealth of a decent valver engine with exhaust/4 branch.
You're full of cheer Paul Doesn't sound good, but no cam or ecu will make an engine have low compression.
