Since Iam such a nice guy right now I will just copy and paste this for you. This is all found in Articles page2 Transmission guide. I just happen to be reading these.
this guy named chet wrote this. NOT ME>
B16A (Cable), B16A2 (Hydro), B16A3(Hydro):
S4C, S80, Y80, Y21, Y1 (optional LSD)
As most of you know the B16A was featured in Japan between the years of 1989 through 2001. This engine has had several different transmissions mated to it causing some potential confusion.
First, it's important to realize that first generation B16A's came with cable transmissions. The Y1 came with optional factory LSD and should have LSD stamped on the transmission. Determining whether or not a transmission has LSD is very simple, just look into the differential and see if its opened or closed. For those not familiar with this, you'll either see a set of gears that form a closed cylinder, or you'll see an open differential with a bar splitting the middle.
Typically these transmissions have had weak synchro's in 2nd, 3rd, and 4th gears with 3rd gears crunching the most. Its also worth noting that all of the transmissions minus the Y1 have very weak open differentials making it essential that you upgrade if your putting a lot of power to the ground.
As far as gearing, these transmissions are all pretty short. Here is a listing of the gear ratios and final drive, courtesy of
www.bseries.net.
1st: 3.230
2nd: 2.105
3rd: 1.458
4th: 1.107
5th: 0.848
Reverse: 3.000
Final Drive: 4.400
In conclusion, this transmission is good for all motor and should bring between 500-700 if its hydraulic while cable transmissions are worth between 400-600. Please be careful that the transmission you're buying doesn't have bad synchro's because a lot of them have been beaten on and this is the first problem you'll have. Plus, if you're making a lot of power, 170 to the wheels, be prepared to replace your differential because these can be broken with regularity.