my 8v digi woes

should the knock sensor stop my car pinking if set to spec?
my mk2 has started rattling like a biatch on light/part throttle since it got hot.
retard timing till it stops and it doesnt want to rev.

thanks

 

It should detect knock, providing it is actually working, the car's dizzy is in the correct position, the vehicle's fuel system has not been contaminated with oil or diesel, the AFM is not set too lean and lastly the airtemp sensor, in the AFM is not shorted to positve.
unshielded pod filter kits do not help either.

 

Standard airbox, tried 2 afms, tried moding one aswell, even tried really richening up the idle co, next is to try my spare dizzi and going to do the lift pump tomorow, anything else i should check. Oil temp does go up to about 115 since the head and cam. I think it might be the castrol so gona go back to mobil

 

It's certainly more likely to pink if it's running that hot.

I'd check and confirm your cam timing is correct initially, then check the fuelling.

You really need a gas analyzer or wideband lambda to poke up the exhaust to confirm what is happening else you are really urinating into a strong wind

Might it be worth you just having one thread about your problems as they are all related to each other....

A trip to a reputable RR would be saving you much grief!

 

My cam is on standard pulley at standard marks, tsr said thats ok, had a handy 4 gas to do co at idle. I dont want to waste money on a rr and then be told you got something wrong get it sorted and come back. Had that before with chipped uk. Tried the single tread thing. Kept getting told it needs a rr session. Then i read people geting it setup then having to retard timing to stop pinking, so a waste money

 

you would be well advised to check and confirm the cam timing is correct.

A pack c head will have been skimmed which can throw the stock timing way off. All depends on how the cam has been cut. A stock pulley let's the car run, but doesn't mean it will run properly. I wouldn't take TSRs word as gospel. Best to check and be sure..

A reputable RR who have sufficent vw knowledge and expertise will set it up correctly first time. With all due respect chipwizards don't fall into that category. A decent RR is worth every penny. False economy not to if your car is running poorly and chewing fuel like no tomorrow.

Any home-brewed setup attempts without the correct equiptment are going to be a compromise. People aren't suggesting taking it to a RR for the benefit of their health

 

You should NOT need a RR to solve the above issue.

 

thats what i thought. if i can solve the problom id pay to get it setup. i listened to tsr cause its their cam.

 

Rattling does not really sound like pinking. As it is making the noise at light / part throttle are you sure it is pinking? Pinking is more likely to occur at large throttle opening when the engine is under more load I would have thought.
Definitely got a Digi dizzy in there and not a carb one with mechanical advance?

 

My advice on using a RR is based on the fact the o.p has had several running issues with his solid lifter head and cam setup on digifant...a visit to someone such as yourself could cure all the problems in one go

@8vDUB-TSR do not cut their own cams..they are Kent grinds from memory, so it is well worth confirming the timing is right by checking for equal lift on overlap with #1 @ TDC

The fact you have a pack c head means the head will have been skimmed. Net result of this is stock cam timing becomes retarded when the cambelt is fitted and tensioned.

Retarded cam timing on an 8v motor is a no no...

 

it definitly sounds and feels like pinking. and yea both dizzis are electronic. im not that silly

 

last time i tried eqal overlap it ran even worse. i try again and see how it goes. but eqal is really far back from standard settings

 

How can you accurately time the cam without a vernier pulley then??

If the cam timing marks on the inside and outside line up correctly at tdc yet the cam lobes on #4 are miles away from equal lift on overlap it really does need a vernier pulley.

Either that or your can timing is a tooth out....

 

A "Pack C head" does not automatically mean it has been skimmed a large enough amount to effect the cam timing. Possibly yes, but not a definite. I have a C and a D in at the moment that have just had a very light skim and they both cc out at the std volume. Still got the vertical bit on the edge of the combustion chamber.

It was just a suggestion. The carb mechanical advance one is still electronic. The amount of eegits that "build cars" these days means you have to check and eliminate every possible screw up they have made.

Are checking TDC on the flywheel with the correct dimple mark? Or are you using the front crank pulley's mark? I have seen numerous crank timing belt pulleys with damage to the keyway meaning that the tdc mark on the v belt pulley is not actually at tdc even if the mark is aligned with the timing belt cover arrow.

 

Didn't mean to imply it was definitely going to be skimmed. More to illustrate that gas flowed heads are generally skimmed as part of the flowing process.

Any skimming no matter how slight will affect cam timing. Sounds like a vernier might be a plan for 8vDUB going on what he has said...

Equal lift on overlap is the best starting point for an 8v cam. If the car runs poorly with it set there then there are other issues...

 

I am sort of reading that there is more to this thread title. In that case you are right.

 

i have a vernier in the boot i took off cause it doesnt run completly true. il try again on eqal oveelap and see how it is. i think it was over a tooth back. vernier has no marks so i had to transfer them cause it is quite old now. i appreiciate the help alot. thanks to everyone contributing.

 

right, for an update, i lined everything up, i dont have the dot just the diamond so iv measured the 12.5mm and marked it, yes its the right wayi took off the rocker cover, and it wasnt as far off as i remember, after swapping the pulley i lined it up to eqal overlap as close as i could by eye.
with it on the standard marks the last bucket was down abit, so i had to back it up abit, witch eqated to a whole 1.5 teeth and a bit of adjustmant on the cam. :O
the dizzi almost lined up with the notch so i left it, as i forgot my timing light and handy gas (rushed out early) i had to set it by eye/ear.
when i started it it bearly wanted to idle and was bogging when i revved it, so i unwound the idle air screw abit and advanced the timing till it revved easy the backed it off abit, so it bogs a tiny bit but picks up, turned it off, tidied up, tried to start it, needed some trottle, so i richened it up abit, started ok.
air screw is about 2 or 3 turns out from all the way in.

does this sound ok or is there anything else i should do? im going to set it up properly but i need to get to work.

could i get it to 6 degrees by putting the engine on the timing diamond and lining it up with the dizzi notch or dont it work like that?
at the momnt on tdc the rotor arm is about 1cm clockwise of the notch.

also whilst im here the 2month old dizzi and rotor wernt to good, cap points smooth white crust, rotor arm had a bit that was bubbled and burnt so i cleaned them up for now.

SORRY FOR THE LONG POST.
THANKS

Neil