Hello everyone,

I recently came across a good deal on a 9th gen trans casing with 8th gen internals and a wavetrac lsd for 800 cad. Ive been planning on re building my transmission for a while now since the car has turned pretty much into a track car with the occasional cruise around town. I was basically waiting for something to break before I decided to dish out money on a rebuild but this deal is too hard to pass on. My plan for a tranny build was to always go with DC5R gearing. From my research, the k20z3 1-3 is the same as the dc5r with the 4-6 dc5r gears being shorter. The plan is to also keep the k20z3 6th gear for highway cruising. Most of the tracks that I go to are hours out and mainly highway driving and I dont think sitting at 4000+rpm the whole way in a gutted car will be any fun. So my main question is if I wanted to upgrade to carbon synchros from synchrotech, would i have to get a seperate 4th and 5th dc5r synchro or are all K series synchros interchangeable? Dont really care for 6th gear but I wouldnt mind upgrading the rest while I have the trans open. My second question is, would it be better to upgrade to lets say a 5.06 FD from a FD2 type r or stick with the oem 4.7. The car just sees circuit tracks never any drag and I plan on just sticking with N/A. If anyone has any experience with a similar setup and tracks their car religiously then any advice will be appreciated.

 

If you want to use the ITR 5th gear and the "stock" 6th gear, you'll have to order the synchros separately. ITR uses dual cones synchros 3-4-5-6. Si uses dual cone 3-4 and single cone 5-6.

The 5.0 FD will raise the cruising RPM by about 225 RPM.

The 4.7 FD with ITR 6th would raise the cruising RPM by about 350 RPM.

I prefer longer FD and closer gears for track use.