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I was of the impression that RB26 and RB25 bellhousings were able to be swapped without implications.

Both bellhousings fit RB series motors and both will fit RB25/26 gearboxes.

Use the slave cylinder, clutch fork and pivot to suit the bellhousing.

I found an RB25 box and clutch for cheap, only catch was it had a custom bellhousing (to suit a VQ motor). So I bought it, found an early (push type) RB26 bellhousing and swapped them over. So RB26 bellhousing on an RB25 gearbox.

Fitted the gearbox into my car only to find that the shifter is now about 50mm further towards the rear of the car, I'd have to cut into the shifter hole to make it fit.

Plenty of people have fitted RB25 gearboxes without shifter position issues. So makes me think that the RB26 bellhousing is longer than the RB25.

Can anyone confirm this, or can anyone take a measurement of their bellhousing (early RB26 or RB25)

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I was of the impression that RB26 and RB25 bellhousings were able to be swapped without implications.

Both bellhousings fit RB series motors and both will fit RB25/26 gearboxes.

Use the slave cylinder, clutch fork and pivot to suit the bellhousing.

I found an RB25 box and clutch for cheap, only catch was it had a custom bellhousing (to suit a VQ motor). So I bought it, found an early (push type) RB26 bellhousing and swapped them over. So RB26 bellhousing on an RB25 gearbox.

Fitted the gearbox into my car only to find that the shifter is now about 50mm further towards the rear of the car, I'd have to cut into the shifter hole to make it fit.

Plenty of people have fitted RB25 gearboxes without shifter position issues. So makes me think that the RB26 bellhousing is longer than the RB25.

Can anyone confirm this, or can anyone take a measurement of their bellhousing (early RB26 or RB25)

Gimme a call tomorrow 0407 111 229 and I will measure the two gearboxes I have. Will need reminding though, hence the phone call

Gimme a call tomorrow 0407 111 229 and I will measure the two gearboxes I have. Will need reminding though, hence the phone call
I called. No answer, so I left a message.

Will take pics tomorrow afternoon.

Edited by daisu

Took some measurements.

An R34 manual gearbox. Bellhousing was approx 400mm, and the rear housing was approx 410mm.

My gearbox, the RB26 bellhousing was approx 400mm, and the rear housing was approx 460mm.

So f**k knows what gearbox it is. It looks like an R33 gearbox (has that slanted section where the shifter plate bolts onto the box).

The gearbox in that link is a Z32 gearbox, I sold it because I didn't want to stuff around with the remote shifter

I am well aware of the differences between a Z32 gearbox and an RB25 box.

The gearbox I have, It looks exactly like an RB25 box, it has the slanted section where the shifter plate bolts down (it doesn't have a remote shifter).

Word from another forum is that it may be from a Cima?

Edited by daisu

Okay, been doing some more searching and found that some models of Z31 were fitted with bigger gearboxes (have the same internals as the Z32/RB25/26 etc) but they did not have the external shifter linkage. So going from the photos it looks identical to the RB25 box.

The gearbox code for them was FS5R30A, which also matches up with RWD navaras. So have a few more leads to chase up now.

Yep, I've confirmed by measuring the length of rb25 and rb26 bellhousings (approx 400mm if anyone wants to know).

I measured the rear housing of a mates R34 RB25 rear housing at 410mm, mine measured up at about 460mm.

Also had another look at some photos of 25 boxes and compared to mine my rear housing has an extra bracket underneath the shifter. It's definitely a completely different box.

Looking at more photos, it looks exactly like the larger box found in late model turbo Z31 300zx (has the same internals as the Z32/rb25 etc). So now I'm a member of auz31 forums trying to get them to give me a hand identifying it.

Phew, who would've thought a 25box conversion could turn out to be such a hassle!

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