Turbo Skyline Gearbox Differences?

[StockyMcStock]

Does anyone know of any differences in the R33 and R32 GTR manual gearboxes? Particularly in terms of strength, but anything that may be useful.

I'm looking at buying an R32 GTR box with the transfer case disabled and need to know if it's the same strength and a direct fit for an R33 RB25DET box which it will be replacing.

As i understand, once you disable the transfer case the GTR boxes are interchangeable with the RB25DET boxes - but not sure on the R32 to R33 mixing.

Any help appreciated, cheers guys!

Edited September 10, 2005 by StockyMcStock

[SteveL]

Does anyone know of any differences in the R33 and R32 GTR manual gearboxes? Particularly in terms of strength, but anything that may be useful.

<{POST_SNAPBACK}>

The gears are to all intents and purposes the same - ie strength is more or less the same, but there are some detail design diffferences. These are basically running production design changes between th 1989 GTR design and the end of R33 GTR production. Improvements were also made to the synchro designs, particularly of 3rd and 4th gears. There's also a miriad of other minor changes to casings, etc

[StockyMcStock]

interesting..... so is there any real reason the 32 GTR box can't be put into a RWD RB25 skyline? transfer case will not be being used obviously, but do they physically fit?

[SteveL]

interesting..... so is there any real reason the 32 GTR box can't be put into a RWD RB25 skyline? transfer case will not be being used obviously, but do they physically fit?

<{POST_SNAPBACK}>

It will physically bolt up to the engine, of course, but you couldn't do it without the transfer case in place as the shifter mounts to it (for a start - then there's things like the tailshaft which is totally different between the GTR and the GTSt). There was a thread sometime back where someone had started bolting a GTR GB into an R32 GTSt and there were some photos, probably be worth a search.

To be honest tho, I can't see why you'd bother as the R33 turbo gearbox is essentially the same strengthwise as a GTR GB.

[StockyMcStock]

yeah the transfer case still have to be there - but you can choose to disable it if the need arises. how, i'm not quite sure actually?

Th GTR box of any series uses the larger RB25-style tailshaft. the only small one is the RB20DET tailshaft yoke which is pretty tiny in comparison. putting the box into an R32 RB20 would need a new tailshaft yoke, but putting it in place of an RB25 would be fine in terms of tailshafts.

i'd normally get an R33 RB25 box too, but this one is quite cheap, certainly cheaper than an R33 box. the R33 box is the one to go for, if you've got the extra $$$ i agree.

[SteveL]

yeah the transfer case still have to be there - but you can choose to disable it if the need arises. how, i'm not quite sure actually?

<{POST_SNAPBACK}>

You could probably at least partially gut it, but I've never done it. I think this has also been discussed in other threads

Th GTR box of any series uses the larger RB25-style tailshaft. the only small one is the RB20DET tailshaft yoke which is pretty tiny in comparison. putting the box into an R32 RB20 would need a new tailshaft yoke, but putting it in place of an RB25 would be fine in terms of tailshafts.

<{POST_SNAPBACK}>

Tailshafts are different in the way they attach to the gearbox between GTR and R33 GTSt. GTR uses a 4-bolt flange, but GTSt uses a slip yoke. I also have a feeling the GTR tailshaft uses a different type of attachment at the diff. If the GTR gearbox is going into an R33 GTSt you'd best use the GTSt tailshaft and have the gearbox end changed over to the GTR flange attachment.

i'd normally get an R33 RB25 box too, but this one is quite cheap, certainly cheaper than an R33 box. the R33 box is the one to go for, if you've got the extra $$$ i agree.

<{POST_SNAPBACK}>

Do the numbers carefully. Gearbox might be cheap, but by the time you add in all the extra expense of fitting it, may work out cheaper to buy the GTSt type in the first place and be done with it.

Edited September 10, 2005 by SteveL

[StockyMcStock]

hmmmm...... thanks for the help. i'll keep thinking!