The Definitive Differential Thread

[Taylortoons]

OK. Here is where I'm at today. Turns out the diff I bought is a manual open, which is probably better since my car is an auto open.

Install is a whole new set of hurdles. I can't find anyone in Dallas to do the work. Seems most performance shops shy away from diff/gear upgrades on the Z. Also, I called Z1 and they were less than enthusiastic about sending them the man diff and having them upgrade to Quaife and 4.08s. They also wanted the car on site so they could switch the companion flange.

I talked with Whitehead Performance in Toronto and they were very helpful. I'll ship the dif to them after the Holidays. They indicated this is not such a big deal and noted they have done several of these before. The companion flange is only $90 and can be installed while they have the guts out of the diff for the upgrade.

I am hopeful that my stock stub shafts will work when I get the diff swapped. If anyone would like to chime in and offer guidance or share their experience, that would be great.

Curious if any SES codes will be thrown when the gears are upgraded. I understand cruise control will be voided. I believe ECU Tek said they can get that back with their tune.