G40 gearbox

[Nedwin1959]

Hi new to this ,are all g40 gearboxes LSD ?

[PeteG40]

nope!

[Nedwin1959]

Now do u tell what ones are? What's the difference between 8p box what
Ones are best

[z3i]

No G40 boxes have LSD's unless they have been fitted as an aftermarket part

8p is from another polo, it has the closest gear ratio sets to the G40 box, but doesnt carry a stupid price tag with it

dont hold me to it but i think the crown wheel is riveted on an 8p box, meaning you cant fit a lsd without great difficulty drilling them out etc

g40 boxes have bolt on crown wheels, so stronger and easier to fit an lsd

[Ben.lopo]

8p are close it's a gt box but still get wheel spin lol don't bother with 085 stupid revs I was doing like 3900 at 70mph on an atv box about 3000 or under at 70mph

[Andy]

8P is a Polo CL 'box, not a GT one! 085 is the gearbox family, not an individual code either. 

[Ben.lopo]

Oops thanks for that Andy  ( me not doing very well at being a smart arse )

[hayesey]

No g40 ever came from the factory with an LSD fitted, all standard open diffs.  Any boxes with an LSD or ATB etc... will have been fitted by someone.  There's no way of visibly telling without opening the box.  But if it has an LSD then rotating one output flange will cause the other to rotate in the same direction which wouldn't happen with an open diff, they'd go in opposite directions.  If it's an ATB (e.g. Quaiff) then I think they still rotate in opposite directions so fairly hard to tell without opening the box, or at least trying to peer in through the oil drain & fill holes.

8P is a 1.3 CL gearbox, it's nothing special at all, people used to give them away or scrap them.  Often not the case anymore as there is some demand for them to put on a g40 as the ratios are fairly similar to a g40 (ATV code) box.  They do have a riveted diff crown wheel though so you can't fit an LSD or ATB into them.  You can with the later CEG coded box which has the same ratios as an 8P but from later mk3 polos, some seats and some small engined golfs - it has a bolted on crown wheel.

[Nedwin1959]

Thanks guys,good imfo ATV now bought

[Matty!]

Good to know there is other options that can be considered. Is the CEG slightly longer or shorter?

I know the G gearboxes have a tendancy to like to eat 5th, has anybody considered cryogenically strengthening this gear?


Just considering this in the distant future.

[hayesey]

1st - 4th are a touch shorter and then 5th is dead long in an 8p and CEG.

[Tav]

Good to know there is other options that can be considered. Is the CEG slightly longer or shorter?

I know the G gearboxes have a tendancy to like to eat 5th, has anybody considered cryogenically strengthening this gear?


Just considering this in the distant future.

I think Yoof and co. looked into bracing it and cooling it with oil a while a go.  Appear to be going down the Golf box route though.

[Yoof]

I have a design somewhere for a bolt on end plate (replace the stock pressed steel item) which had a carb jet fitting in it and pickup/feed for an oil pump.

Basically idea was to scavenge oil (cool it) and spray directly over 5th.

It gets you around the lack of lubrication at high speeds, but ultimately doesn't solve the problem of too much power/grip for the gear(s) to handle (hence the 02J conversion).

Another option is to drill the end casing to allow more oil flow to 5th, this is something JP did on a few boxes, unsure if this has ever been proven to help though.