Gearbox replacement not making sense

[baby_mikey]

Hi guys,

I recently had a gearbox issue on my GPX mivec tip box. End result was that it needed replacing. I have sourced another tip box from a mivec of the same year. However, the replacement gearbox is in but the existing driveshafts aren't going into the box far enough. The splines are the same (25No.) but the existing driveshafts are about 1cm too long. I have tried to get the driveshafts from the replacement box but they have been mangled, but they are slightly shorter.

Now, i have found another gearbox from a GR which has the same number of splines as mine and but im not sure what else is different? I thought the difference was in the splines which means that i have a GR gearbox on my mivec!

My questions to the experts are: Is it possible that my gearbox on my mivec is a GR tip box (i was told it was replaced at somepoint)?
and can i put i GR box on my mivec, is it a straight swap?

Thanks guys!

[colm_mcm]

AFAIK the GR has a different final drive ratio so you won't get as much accelleration

[Myfeckin FTO]

Think I remember reading somewhere that there are a couple of different length ends on FTO driveshafts and also two different number of splines (25 and 27). AFAIK the issue you are having is most likely to do with whether or not your FTO (or the donor) had ABS as these would have different lengths over the non ABS FTO.

[steelroe]

What year is your FTO and are you sure the donor box is frokm a MIVEC. If yes then what year was the Donor FTO

I have a few tip boxes from both MIVEC and non MIVEC FTO's if you are interested. Also have plenty drive shafts so should be able to sort you out .Give me a call.