OK, I've searched and can't find exactly what I need.

I got sweet deal on a super clean 91 CRX HF with b16 swap. Even has the JDM backseat!

Anyway, the gearing is insane. It's basically around 5k rpm between 75-80mph. Nope, ain't doing it. I picked up a 90-91 LS tranny for $200 local. I originally was going to just swap in the LS 5th, but decided to swap the whole mess over. Long story short, I'm going turbo later and want nice comfy cruising gears. The LS internals dropped right in the b16 case. Any problem with this before I put back in the car? Basically I swapped over the mainshaft with all gears along with countershaft and all counter gears. Also swapped the diff. Will there be any issues with the bearings? I just lifted it up, and moved it to the b16 case. I cleaned the mating surfaces and threw on some rtv black, ready to throw back in car. I would have finished but I was sent the wrong clutch and didn't know until I was putting it on.

I know I could just do the whole LS tranny swap but I wanted to open it up and check it's wear. At 4am and changing my mind 3 times, I grabbed all the LS internals and moved them over. Btw, these are both cable non LSD.

 

Everything I've read seems to suggest that this is OK. I had some concerns based on a few random posts about the bearings on the differential possibly being different. There are two of them, 1 on each side of the diff.. Are they the same? If not, can you "shim" them without taking the case apart? I don't want to throw this back in until I know. Thanks!

 

Yes u must use a feeler gauge to measure the shim needed

 

You need to shim the mainshaft and differential. Procedure and part numbers for the OEM tools needed are in the Helms manual.

 

I just remembered I used the b16 bearings on the ends of the mainshaft and countershaft so they are an exact fit

So now it's just the question of the differential bearings.

 

It's real easy to check diff
I do it by only putting diff in casing and torque the casing bolts then use a feeler gauge to put in between diff bearing and casing then

 

No, you still need to shim the mainshaft.

 

I've done 5th gear swaps before but never the whole gear set's/final drive and differential.. this goes to show just how much one needs to research and know before assuming it's plug and play.

I used the existing shims. I *think* there were two on the bottom of the mainshaft but it all went back together so nicely. I didn't check and clearance's (which I should have, no doubt), but it's all back together and driving great. I'm not getting any grinding, whining, or anything. It's as smooth as silk. I filtered the oil that came out of the tranny and reused it for the first few drives to flush/clean out the tranny. Drained it and put new penzoil syncromesh in. So far so good. I sure hope it's within 'spec'. hmmm

edit:
btw, I love the new gearing! IMO it's so much better than the b16 gearing (which was really a design for Japan, not US roads, but it's just the way it should be. My 4th gear is now where my old b16 5th gear use to be... and I don't really notice it being that much slower. I'm not racing the car anyway and I plan to go turbo later so the longer gearing just makes more sense.