Jump to content
HybridZ

RB25 Trans no longer needed for RB26/Z32 Swap


Booztd 3

Recommended Posts

Guys

 

Originally I purchased an RB25 Transmission because when I was researching the swap, I was under the impression that ONLY an rb25 bell housing and input shaft would work. So I sourced one for 800+125 shipping. During that time I was questioning whether or not the RB26 bell housing would work, however I couldnt get any one to get me measurements or take pictures, and RB26 trans arent just laying around everywhere.

 

Anyways, fast forward to yesterday. After completion of the RB25/Z32 trans mating, I decided I should still have a look at the RB26 trans, since it was just setting there. Here are the pictures of the RB25 Bell Housing & Front Cover, next to the RB26 Bell housing & Front Cover

 

My new RB25/Z32 setup on the left, RB26 stock trans on the right

 

RB25_Trans_55.JPG

 

RB26

 

RB25_Trans_56.JPG

 

RB25

 

RB25_Trans_57.JPG

 

I did not get a picture of the very top of the bell housing to identify how far the input shafts stuck out on either one, but I remember eyeballing them and I cant physically see a difference. Remember from my 'how-to' post that we measured the lenght of the RB25 in put shaft and the Z32 input shaft and the Z32 was ~1/8" longer.

 

To summarize all of this up. IN THEORY - the only thing you need to do in order to bolt a Z32 transmission up to your RB motor is swap the bell housings. The input shaft lenghts should be negligible, and will not effect anything. If anything, the Z32 input shaft is longer, so you may need to take a grinder just to shave some material off, but I dont suspect this being the case.

 

In my defense, since I had already ordrered the tranny and done the research, and I knew that my Z32 trans had some grinding issues, I went ahead and rebuilt it. I could have saved alot of $$ and just pulled the RB26 bell housing off of the RB26 trans and swapped it with the Z32 trans.

Link to comment
Share on other sites

You can also use a z31 turbo trans.

 

Evan

 

Nice car btw, I saw the pics on the rb forums elsewhere.

 

 

 

Yep, and the 88-89 Z31 Turbo trans is alot closer of a match to the RB25det trans than the Z32 trans is.....

 

Here is a Z31 Turbo trans. Its virtually the exact same...

 

4221062038.jpg

Link to comment
Share on other sites

I think he may be refferring to the fact that the rb20 tranny will bolt up to a rb26 BUT the bellhousings will bot interchange between the rb26 rb25 and vg trannys. its allot smaller then the others

 

so the rb20,rb25 and rb26 bell housings are the same? if so cool! Because all i need is the bell housing

Link to comment
Share on other sites

so the rb20,rb25 and rb26 bell housings are the same? if so cool! Because all i need is the bell housing

 

 

NO ITS NOT!! the only thing the same about a rb20 trans is it will bolt up to any of the three motors....

 

The rb20 trans front bell WILL NOT bolt to the rear section on a rb25, rb26 or Z32 trans.

Link to comment
Share on other sites

Guest Straight6

But, how strong is a Z32 Trans versus an RB Trans? I was thinking this is a perfect solution for my project, yet I would prefer to stuff a Getrag along with the RB then to use a Z32 Trans, no?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...