So I'm going to be looking into a replacement transmission. Finding a replacement Si transmission can be difficult because there are no markings, stickers or whatever to sort an Si trans out from the DX, etc. (If this is not true, someone tell me because I haven't been able to find an answer to this.)

Anyways, it occurred to me that maybe a transmission from a 88-89 integra would be a good choice; it is coming off a D-series after all. The gear ratios are very similar to the Si gear ratios. Has anyone here ever heard/seen this done? I haven't been able to find much yet, and I plan to visit some junkyards so I can actually see what may be different. I think the 88-89 integras had intermediate shafts to reduce torque steer, but I'm not sure what else may be different(and if it all bolted right up that could be a good thing).

I'd like to guess that it would be a direct swap, but will be investigating to find out for sure. If any of you have input regarding this please share. Thanks!

 

86-89 Integra transmissions don't bolt right up to a 88 and up D-series block (most of the bolt holes match up, but not all) - they also have different mounts (mount at passenger side is not on top, but is in front) - they have a different input shaft which won't fit into the 88 and up flywheel (you could use the Integra flywheel and clutch) - they do use the intermediate shaft and larger Integra type axles (the Integra intermediate shaft won't work on the 88 and up D-series blocks)

this is the 86-89 Integra CG transmission:



this is the passenger side mount:

 

So much for that idea.

Guess I'll just have to be diligent in finding an Si trans, or maybe a ZC trans. The ZC had an intermediate shaft also, so I wonder what axles I could use, or if I could just take off the i-shaft and use stock USDM axles. :thinking:

 

the ZC transmission uses the ZC intermediate shaft and the larger 90-93 Integra axles - you can't use the stock axles with the ZC transmission as the end that goes into the transmission is too small

 

Well, I need to get this done. I've been looking around and Si trannys are hard to come by in good shape and reasonably priced. I'm thinking of just getting a DX tranny. The only thing different is the final gear ratio, so that may take away from acceleration but may give me better gas mileage. At this point I just need to get a reliable trans for my long drive south. Any thoughts on this?

 

I would try to be patient & keep searching for a Si tranny. So what yr is your Si?

 

Nevermind, I got a '91 Si tranz. It better be in as good of shape as the seller says it is. Oh, and mine is an '89.

 

Good luck & hope no grinds

 

Ok boys, note to selves...

I wish I caught this earlier. The trans I picked up apparently came out of a '91 CRX Si, but I found today that it won't work for my setup. Either the seller lied, or he was not the original owner and had no idea the trans was not original. The trans has a 21 spline input shaft, which only came on '88 Civic's and CRX's. 89-91 trans have a 20 spline input shaft. My stage 2 clutch won't fit this spline and is practically new, so I'm not willing to get a new one. I'm just going to have mine rebuilt.

So, if you're looking to replace your trans remember to check for this. It's an easy thing to overlook, so be vigilant. Don't forget to look for cracks in the housing, like at the fill and drain plugs.

 

Thanks for the heads up. I bought a trans without doing research on my eg and found numbers scratched off. I hope it's an Si, but won't know until it's installed :hs: