G40 Gearbox options

G40_Mike_ · February 07, 2012, 12:34:44 PM

Hi,

I am in desperate need for a G40 ATV box, but simpley cannot find one, so I'm going to have to get an alternative for now.

If I recall correctly, the 8p gearbox is an option, but has shorter ratio's, but what other short term options do I have?

Many thanks

Mike

PeteG40 · February 07, 2012, 12:35:30 PM

any mk2/3 box will fit. but 8p has nearests useable ratios. A gt box is very short geared!

G40_Mike_ · February 07, 2012, 12:38:33 PM

Quote from: PeteG40 on February 07, 2012, 12:35:30 PM
any mk2/3 box will fit. but 8p has nearests useable ratios. A gt box is very short geared!

You are FAST!

Thanks again Pete! (I will send you those charger pics as soon as I go and collect it!)

Thanks
Mike

grungeisdead · February 07, 2012, 12:57:44 PM

ive been running a CEG gearbox for the last year on a standard G40 with some very slightly mods and found it more than usable day to day, only gripe is its a little high revving at motorway speeds, but still climbs to silly figures on the few occasions its been pushed

hayesey · February 07, 2012, 01:15:07 PM

CEG is basically the same ratios as an 8P. Either are fine, there is nothing else closer to the ATV really.

gavin.starr · February 07, 2012, 05:03:27 PM

Excuse my lack of knowledge. I have heard alot of this gearbox mentioned since i joined but never thought about asking what it is.

Whats the difference between ATV-8p etc...

Is the ATV box just a specific box that was built for the g40 and how do you go about finding out what box you are curently running Ie: is there any markings on the casings.

Cheers

hayesey · February 07, 2012, 05:19:37 PM

different gear ratios is the main difference.

there are some other differences though. Older (pre about 1993) boxes such as the ATV, 8P are basically the same except for the ratios. Then there are later boxes such as the CEG (which was a replacement for the 8P and appeared on later mk3 polo 1.3 CLs as well as some small-block engined golfs). There is also a later code G40 gearbox but I forget it's code! The later boxes have a couple of differences, the main one is that one of the driveshaft flange cups is longer (and hence the driveshaft a touch shorter) but you can swap an early cup into a later box without too much hassle (think you have to put an older spec oil seal too though).

Oh, then the other difference between boxes is that GT & G40 boxes have bolted on differential crown wheels which are stronger and suitable for fitting an LSD to. Pretty much all other mk2/mk3 polo boxes (including 8P) have pressed on wheels which are no good for fitting an LSD too. If you find a CEG box, it can have either, very late ones have a bolted on wheel, most have a normal pressed on one.

To cut a long story short, you want to be looking for an 8P as it'll definitely go right in with no problems and has the closest ratios to the g40 box. It used to be the most common box knocking about, I've had a few for free over the years (but I don't have any left now, they've either been fitted to cars or killed or stripped down for parts). But it is possible they are getting rarer now as these older 085 gearboxes are getting rarer in general.

Matty! · January 20, 2014, 07:21:27 PM

Sorry to resurrect...

Does anyone know at what MPH at GT gearbox tops out at?

Also I've been thinking about this for a short while, I know a few of you boys have stripped a few gears from time to time and was wondering.

Is there anything you can get don to strengthen the internals on the boxes? or even get new ones? I have been told they can be cryo treated in some way to increase strength but not sure.

Not after it for me personally yet just interested in general