I am confused as to what the difference is between a cable S1 tranny and a cable J1 tranny?

I am in need for a tranny and I have the option to get a hold of a cable S1 LSD tranny or a cable J1 LSD tranny.

 

Neither of those trannies ever came with an LSD, so you're not gonna find one anywhere(unless it's aftermarket). They both have the exact same ratios, which are very short and somewhat similar to the Type-R. One came in the Integra, the other in the Civic. Be careful, as there is also a B18A S1 transmission from the 1990-91 USDM Integra with longer ratios. There is no difference in the casings, so make sure you buy from a good seller.

The only tranny from the 1989-91 era with an LSD is the Y1. The ratios are a cross between the B18A S1 and the B16A S1.

 

and to add..
if you want a really good cable LSD tranny, but its kinda hard to find, keep a lookout for a JDM YS1 LSD tranny. Same gearing as hydro B16 tranny w/LSD.

 

Thanks for the info.