JDM B16A & Y1 Swap into 92 GS

Hey guys so I picked up a '90 B16A and Y1 (LSD) from my friend, I understand that the intermediate shafts between the Y1 and my 92 YS1 (Not GSR) are different lengths so for now I am thinking of just going to use my YS1 with the B16A but I was thinking of swapping the differentials over.

The reason I want to swap diff’s over is because the Y1 needs the synchro’s to be replaced and also the intermediate shaft size issue, my YS1 trans just needs the clutch to be replaced which I already have so swapping the differentials is easier then waiting to purchase then install synchro’s sometime in spring which means I cant drive my DA if I go that way.
I don’t understand how the Y1 intermediate shafts swap into my DA. All I know is that the intermediate shaft I have and the Y1 intermediate shaft are different length and need to be swapped around to work (but my friend didn’t tell me which shafts to use because he isn’t sure)

Could someone help me out with this since in the summer once the synchros are replaced and I swap gears around between the two transmissions I want to reinstall the lsd then put the Y1 into the car.

Thanks!

I thought the only thing different was the splines on the clutch.

The intermediate shaft is somewhat irrelevant, just use your stock intermediate shaft and stock axles. You can you those parts regardless of which trans you end up using.

You cannot swap internals between the YS1 and Y1. My suggestion, dending on your budget:

  1. Sell the Y1 and you existing YS1 and find a used short geared YS1
  2. sell your Y1 find a used hydro trans (short geared, preferably ITR) and put those internals in your existing YS1.

How about changing the differential over, do they at least swap over?

I’m pretty sure they do not, but I’m not 100% sure about that. Why would you want to swap the diff? The Y1 has decent gearing but is old and difficult to find parts for. Putting an LSD in your YS1 is a waste of time - you’ll end up with better traction but completely worthless gearing and the net result will not be a good setup. Given the choice I’d recommend better gearing with an open diff vs tall gearing and an LSD. The car will be much more fun and will be faster with the better gearing.

The gearing between a Y1 and YS1 arent to far apart, if it was geared shorter then I would want to spend the money to get synchro’s. The reason I dont want to get another transmission is that right now I just want a running car and the synchro’s on the Y1 are questionable, but I guess for now I should just use the B16A and YS1 together till I either get a shorter gear transmission or replace the Y1 synchros.

Maybe I will open up the Y1 and see if its actually the synchro’s or if there is just a bunch of metal floating around, because my buddy said when he drove the car home it didnt grind much but I didnt really get a chance to check it out before he pulled the engine and transmission. He said the owner he bought it from knew nothing about cars, so the trans fluid could be covered with metal or expired and just not lubricating properly anymore.