Looking into maybe getting this done. It's intended for a '83 MK1 1.8 GTI that'll have it's original DX block / head swopped out for those from a '86 1.8 EV which'll have had a few mods (1900cc / ported / some other stuff) Will hopefully be utilising the original flywheel / 020 'box etc. from the MK1. The car'll not be thrashed or raced... it's more me indulging in period, old school tuning for the sake of it and I'm not looking to eke out the very last gramme of weight / happy to keep things moderate. There's a place locally that might be able to help, however he's asking me questions I don't have the knowledge or experience to answer. As a starting point he'd be able to make good use of images of a similarly lightened wheel that's already been done, from different angles ideally. There's a thread on the forum here - https://www.clubgti.com/forums/inde...eople-are-running-lightened-flywheels.222056/ that I've already filched some from. The images below are of the flywheel to be lightened, showing the part numbers in case it matters. And finally - what purpose do the 2 x squared lugs perform, seen above the VW Roundal / Audi emblem in the first image ? I can see them still there in some of the post lightened thread images, do they need to be retained?
Wish I could help, but I am taking my gearbox off tomorrow and will look at the numbers on mine. Not lightened tho
Pretty sure the lugs are for the VAG 1367 diagnostic kit to sense. It has a probe that plugs into the green capped hole in the top of the gearbox which without the diag tool you just shine a strobe into to set the timing with the more conventional dot and diamond marks on the flywheel. The flywheel locking tool locks into the ring gear that the starter motor uses.
Yes thats right. Stealth racing have that tool for the older cars. I remember Vince trying to use it on mine once it had a lightened flywheel from Hotgolf!
I must say I wouldn’t use someone who doesn’t already know how to do the job for something like this. It’s really a specialist job and needs to be spot on otherwise there is a risk of, at best, having to remove it and throw it away or, at worst, ruining your engine. I’m surprised there isn’t something available off the shelf?
Thanks all... he's been at this (and other engineering) for a professional life time by all accounts and gets nothing but praise for his attitude to potential customers / his work (plus I've fallen on my feet for once and found someone who's just 15 minutes drive away for a change) In fairness to him, rather than having it from me and giving it back done with a bill, he was taking the time to discuss what can potentially be done against what I wanted / expectations were, to see if they matched. Good example is him noticing the pick up points immediately... I didn't even know what they were for. Idea was that between us and using the images he could better show me what was safely doable and go from there, so the issue was more my lack of knowledge / ability to follow the technical side of things. He's going to balance the crank in conjunction with the flywheel, so while it've been very handy posting stuff off, it wasn't really viable on the extra cost alone.
The main thing is getting the gap tolerance between the outer (mating) face of the flywheel and the friction face spot on. If it’s out by even half a mm the clutch will either slip or not disengage so you won’t be able to get a gear. Ask him how he will achieve this in the machining process as I’ve heard it has to be ground rather than machined on a lathe because on a lathe the tool post can “bounce” just a fraction (but enough) off the work hardened hot spots that make up the friction surface to throw that spec out. Don’t forget, a heavier flywheel helps smooth out your idle.
So, you’ve a std mk1/2 dual pin 9bolt flywheel. no, you don’t really need the two lugs and I’ve only known 2 people to have the correct tool. Yes, it can be skimmed/faced in a lathe, yes it’s easy to set the friction plate depth if worn or requires facing. You will not lose torque. The engine produces that regardless of flywheel weight but, you will lose inertia and long drives will use more fuel. If your isv is buggered it’ll hunt or stall as you slow down. Get it wrong, they can shatter!
