Hello, had no luck in another thread so thought I would dedicate one to it - On wednesday im having my cam belt and tensioner replaced, at the same time I'm going to get him to put in the GTI cam I have, what should the timing be for this, and should it be done with or without the vacuum hose attached to the distributor? Thanks
Hmm, im pretty sure that installing a GTI cam in a 1.6 driver changes the timing, just dont know what it changes to? Anyone?! Is it the GTI timing thats in the haynes?
You need to make a new cam timing mark on the cam shaft, & the ignition timing is done to a GTI (6degrees I think). Someone will hopefully confirm this.
Ok, so 6 degrees BTDC for the ignition timing, what do I have to do with the cam timing?! Does anyone have a diagram, I've had a search but couldnt find anything. Its going in Wednesday, so running out of time - I trust my mechanic, but this is a bit of a mix and match and I cant expect him to know how it should be set up off by heart, so want to go in prepared! Thanks for help guys
Making a new timing mark on the cam shaft is in the Haynes. Theres a pic somewhere on this forum - ill have a quick look.
Where are Mike H, rubjonny, EZ pete when you need them!?!?!? Someone must have some expertise on this?!!
you use the original setup method on the old dizzy, and use the GTI method + new 6 deg mark on flywheel if you fit a k-jet GTI dizzy
Gawd, now I'm really confused, conflicting information - So I have original 1.6 EZ dizzy, with GTI cam going in, is this set to 6degrees BTDC (with new flywheel mark) or is it set to original 18degrees BTDC (which I think is original setup?!) Waaah, im sure it shouldnt be this complicated!!
no I meant what I said (makes a change ) with the original EZ dizzy set it up as per factory. If you put in a k-jet GTI dizzy make a new 6deg mark and time it up as per k-jet GTI
Cool, its getting less complicated now, thanks rubjonny Why do people fit the k-jet dizzy when fitting the gti cam? Does it make a difference in power or something, cos if this is all correct it seems much easier to stick with the original, also wouldnt I need some sort of engine management for the kjet dizzy?
the k-jet gti dizzy has an ign curve better suited to the cam, but whether it makes a big enough difference to bnother I dont know. I did this very thing on a a mate of mine James' MK2 1.8 carby, I'll ask him if it made a noticable difference.
ok, so just to recap, finally- all that needs to be done after fitting the new cam, belt, tensioner etc, is to time it up to normal 1.6 EZ measurements (ie 18degrees BTDC, IIRC)? Thanks for your help, mr Rubjonny!
yep, just need to check if its vac hose on or off, I cant recal! I possted up idle/co/timing pdf guides in my elsawin faq
when i fitted my gti cam i timed it up using the mark an the back of the camsahft pulley that lines up with the top edge of the head obv without the cam cover on then once that was fitted fitted the cam cover again started the engine and removed vac hose then moved the dizzy till it retarded the timing and then turned it slightly till it ran nicely again i had no problems
massive difference! when it was rolling roaded before it made 125bhp but they only took it to just over 5k as it had no advance, with the gti dizzy it screamed round to 7 (more in the lower gears if you got carried away ) Definitely a worthwhile mod (especially if someone else does it for you!) and really did make a difference, although i did have a silly cam that made power well up the rev range, probably higher than a gti one does?
Hmmm, Im confused aswell. I thought you need to time to a GTI (6degrees) when installing a GTI cam. But Mr Jonny has cleared things up for us.
By all means try it both ways, but I'm pretty certain the reason the driver is timed differently is down to the dizzy, also on one the vac hose is connected, the other its disconnected. Cant remember which is which, but its definitly the opposite on GTI/Carb dizzys!
will it say for definite in the haynes d'ya know? The vacuum bit? If I were to hazard a guess I would say it should be on, because doesnt a carb dizzy rely on the vacuum advance, if you time it without the vacuum circuit being closed it might not run right?..... maybe?! Having said that, many people on here are reporting punchier throttle response from not having the hose attached when timing! It really is confusing!
