need gearing opinions

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Senior Member
alright so the car in question is my 2000 Si. It currently has the stock B16 jackson supercharged @ 6-7psi and usdm itr trans, but I'm in the process of building a gsr engine that will be jackson supercharged @ 9-10psi. So my question is, what would be the best gearing setup for the new motor- the usdm itr trans in the car now, a gsr trans with lsd, or itr gearing with an ls final drive and itr lsd? The car is my nice weather dd and sees some autoxing, no drag or street racing so top end is not really a concern although lower highway rpms for mpg is definitely a plus.

Use the itr trans. It has the shortest gearing, which will help at autox, and comes with an lsd.
thats kinda what I've been leaning towards, I love the trans thats in the car now but I was just concerned about the new build being too much power for that short of gearing. Thats why I was considering one of the other options I mentioned. Although whatever ends up going in there will have an lsd so that doesn't matter either way