That Supra TT Auto Torsen T-1 looked great! But I'll bet your new clutch style diff felt like a step up (even though you felt the street style RS spring conversion was needed).

You've got the right approach with all of this! I might also try to pick up another MKIII R154 at some point just to keep as a rebuildable spare transmission.

Having use of the shop space and lift bay from your work(?) is a huge leg up for this work as well!

I can't wait to hear your impressions of the newly rebuilt and modified LSD once you get it back in and broken in!


Seconding Rudy's response to your question-- I'm also still running at the stock boost level in sequential mode on my twin turbos (USDM twins which I recently had rebuilt).

I have wanted to pick up a used HKS EVC6 but I'm in no hurry. I already have an old Greddy boost cut defeat device (SW20 type) but it hasn't been installed yet. Also like Rudy I'm enjoying the sequential powerband a lot. My only issue is that a couple of the valve actuators have become a little lazy from age leading to occasional boost inconsistencies but it's mild.

Also since my ECU is an OBD1 type I have the more pronounced power dip right around 4,000rpm compared to OBD2 ECU's or JDM VVT-i ECU's that operate sequential twins but similarly I'm not that bothered by it.

I think I might install an electronic sequential/TTC switch however but it's not something I'd want to use very often.

Also Rudy-- if your JDM stock twins came on a factory 2JZ-GTE VVT-i engine then I believe you should have steel rather than the ceramic exhaust wheels that earlier JDM stock sequential twins came with.

 

Craig,

I've heard the same thing but am in the same boat as you. I don't mind keeping things simple for now and overall I'm super happy with how my car performs being stock turbo and ecu. Later down the road I look forward to upgrading but I'm trying to not go too far down the rabbit hole until I have the funds and state of mind to handle it haha!

 

Craig, I actually just swapped my open 4.083 for a stock TT auto with torsen. I swapped the whole pumpkin. I just had the cover off to reseal it is all. 😎

 

Ahh! I was confused by your post above referencing May 2021. You'll like the Torsen T-1 a lot! I've been happy with my TT Auto Torsen T-1 LSD (first set up with a 4.272 ratio and post engine swap back to its original 3.769 ratio) since 2011. It's a great all-rounder LSD.

Only point of caution: when it's wet out or even if you drive through a wet area take care and avoid punching the throttle too much. I think all of us are used to LSD equipped cars by now but with T-1 Torsens they can under circumstances like those have a tendency to snap back after a traction loss in the wet (usually to the left) which can catch even the best of us off guard. This is because Torsens dynamically adjust torque rather than locking like a clutch type 1.5-way or 2-way LSD. Torsen T-1's have this characteristic more than the later T-2 design.

Since I encounter wet weather a lot I always get tires with superior wet traction ratings in addition to the dry performance characteristics. That has helped avoid any troubles with the Torsen stepping out in the wet unnecessarily.

Just something to be aware of if this is a new diff to you. If not then disregard as you'd be used to it by now

Above a 450whp-500whp tune and generally the T-1's biasing characteristics tend to be less predictable/effective. At the 400whp-ish level you're at it'll be great!


Rudy, I am with you on that. I don't mind keeping my engine stock. It's part of my overall CA emissions passing goal anyway and with almost all the big projects done now I'm happy to just keep it simple, save some money and enjoy the car as you are with your SC.

However when I find a good deal on an HKS EVC 6 in good condition I'll certainly pick one up. Later I think a mild bump to 15 psi wouldn't hurt at all on 91 octane. Certainly not on the 93 octane in my current area.