Someday soon (within the next few years), I'd like to begin using an LSD in my 96 LS-turbo setup. I want to set aside the option of using an aftermarket unit such as Quaife or OBX for a moment, and just look into swapping the whole tranny.

First question: Do most jdm b18b trannies have an lsd? Where would be a good place to find one? I already called osaka and they don't have any.

Second question: Has anyone used a b16 tranny (w/lsd) on an LS-T setup, in autocross? If so, how did those gear ratios work out?

 

First question: Do most jdm b18b trannies have an lsd? Where would be a good place to find one? I already called osaka and they don't have any.

NO, they are very very very very very very rare....in fact i don't think that is even a factory option

Second question: Has anyone used a b16 tranny (w/lsd) on an LS-T setup, in autocross? If so, how did those gear ratios work out?

used a 4.785 b16 tranny on a b20vtec turbo setup....geared to 145....when do you need to go faster than that?

b16 with lsd would make a world of difference....imho

 

b16 trans with an lsd is definately the way to go. for boost that gearing will be perfect for autocross as well as drag (if you decide to take it down the strip)

 

ive actually never heard of a B18B LSD option! ever! B16a w/ LSD seems the way to go.

 

I autocross, and borrowed a B16A non-LSD tranny for 3 weeks. Although I never autocrossed with it, I thought about it and decided against the shorter gearing. Surely it would accelerate faster on the straights, but IMO with the stock LS 6900rpm rev limit it just didn't make much sense for autocross because your top speed in 2nd is ~51mph. In most of the autocrosses in my area, I top out at about 55mph on at least half of the events - sometimes more, sometimes less, but usually ~55mph, which is right where my rev limit is with the stock LS tranny and 4.40 FD (used so I can run the stock ITR LSD). I just felt that having to shift or bump the limiter just a couple/few mph short of the speed I often reach on straights would disrupt my run quite a bit, and may well end up being slower, not faster. I would think with a turbo setup you would run into this problem even more, being stuck between 2nd and 3rd all the time. It could be different though, depending on the layout of the courses.

If only I had a higher redline, I would have run the shorter gears in the B16 tranny no question. The car pulled out of corners quite a bit better. But with the low redline and the nature of autocross vs. on-track driving, I think it would be more of an irritating and time-consuming disruption than an advantage. Just my .02.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spock_rocker &raquo;</TD></TR><TR><TD CLASS="quote">ive actually never heard of a B18B LSD option! ever! B16a w/ LSD seems the way to go. </TD></TR></TABLE>
Yeah, I've never heard of a factory B18B LSD option in any country. It was an option on the JDM B18C (non-ITR) but even those are quite hard to find.

 

OK, back to the aftermarket LSD option, OBX in particular. It seems like installing one of these is a major pain in the ***, unless your used to doing a lot of transmission work. I'm planning to install a new clutch and flywheel next weekend though.

I'd like to hear from anyone who has used an OBX LSD in autocross, to see if it would be worth the extra hassle.

 

I helped my mechanic/racer friend install mine, and it isn't THAT hard if you already have the tranny out.

As anyone with an LSD will tell you, it's a godsend in autocross. It completely changed the way I drove my car and definitely shaved a lot of time. SO much better. I'm not saying it's the LSD that did it because it was probably mostly improvement in my driving, but in my first 3 autocross seasons I won 1 event out of probably 15-20. Since getting my ITR LSD in I've won 15 of 18 and set 4 FTDs. Again, an LSD is only a small part of that, but it's definitely a factor that contributed quite a bit.

 

The B16 / Type-R gearing is too short for a Turbo LS, IMO. The LS gearing is too long, and the LSD options are limited. Right in the middle between those two options is the GS-R tranny, which has good gearing without being too short, and it can easily take an OEM Type-R LSD. I'm very happy with that setup on my turbo LS.