Hi,
I need to use the G for a few motorway miles everyday soon, is it possible to change out the 5th gear and change the final ratio to give lower rpm's for cruising?
If this is easily done (as on VW T4's) can someone please recommend a gear set or gearbox to change to? A guide would also be very helpful or any information on ratios vs rmps etc.
Thanks in advance!
Scott
if you take a 5th gear from an 8P or CEG gearbox then you can put that into your G40 box and it'll give you a longer 5th.
One of my polos has had this done (not by me) but I find it quite annoying. You have to get the revs up quite high in 4th before changing to 5th and even then there is no acceleration as you are out of the power band. I also find that in light traffic you are constantly having to change back down to 4th when you slow down below 70 whereas with a standard g40 box it's just much nicer to drive in my opinion. When the clutch goes on this car I'll probably change the box for a normal g40 one.
I remember being in the PSD 'tin can' with the same modification and it was awful. VW did a good job of spacing the ratios correctly, if it needs longer legs change the final drive.
I found this mod good for me on a supercharged engine , bad point being the syncros crunch on quickish shifting.
Saved shed loads of fuel on motorway runs though.
Many thanks for the replies guys.
Andy, any advice on how to change the final drive and what to?
Karlos the jackyl, what was your mod?
Much appreciated
Scott
he means putting a longer 5th in.
to change the final drive you'll need to do some research into which 085 box you can get a longer drive out of. You'll need to make sure the final drive you choose has a bolted-on crown wheel on the diff side. You'll also need the entire layshaft from the box as the small side of the final drive is part of that. It's a pretty big job really, complete gearbox strip down.
Meanwhile changing 5th is quite easy you can even do it without removing the box from the car as it's just under the black cover on the end. But I think it's a bad idea. I can't see it saving any fuel unless your drive is on a motorway that is always very quiet and you can just sit at 80 or 90 without getting slowed down.
I didnt touch the final drive , there's no need too really
I just changed the 5th gear , Motorways cruises were good as my car used to drink fuel like going out of fashion on the standard 5th gear , the saving was very noticeable . If i needed to overtake I'd just knock it down a peg or two and dart off.
But you need to match it carefully to suit your power band/revs wheels size etc.. best to use a calculator to work out the ideal ratio.. I think there's one kicking about on the forum somewhere
I never used mine as a daily driver so the putting up with the cons was never an issue.
Quote from: eggeyes on August 29, 2012, 12:05:55 PM
Many thanks for the replies guys.
Andy, any advice on how to change the final drive and what to?
Karlos the jackyl, what was your mod?
Much appreciated
Scott
also, I guess it depends what gear you use of course!
And how much power/torque you're making, and at what rpm.
For a standard G40 VW did a good job of spacing and matching the ratios. 8P 5th is just too big a gap IMO.