Am going to replace clutch soon and want to get an LSD. For a few hundred more I can find an ITR tranny. Realisticly what gains would I see with the tranny and would it bolt right up? Is it worth the money and does the factory lsd hold up? Bottle fed right now, some day hope to be boosted. Seems to be a common swap to a GSR, am I right?

 

The ITR trans has closer gear ratios and is shorter overall. Cruising at 70 you'll be close to 4000 rpm instead of 3500 for the GSR trans. First is a little taller with all the gears closer to each other. It will fill the hole between first and second so the revs can stay above 5800 on a 1-2 shift. The factory LSD is not supposed to be as strong as a Quaife but I have not heard of people breaking them. You may want to check in the ITR forum. From people I have talked to and data I've seen, I think 1/2 to 2/3 of the acceleration advantage the ITR has in 0-60 or 1/4 mile is from the better gearing. I have not done it myself due to being illegal in DSP autox. I know at least one person with an ITR gearbox on a GSR, so yes it does bolt right up.