Best differential for racing

[Shifty Powers]

To start, sorry if this isnt the best area to post this. The racing section and whatnot is a little dead.

But I am getting ready to redo the entire rear in the car and I am having issues on figuring out which differential to get. The car is a 96 cobra and will be slowly set up to be taken off of the street and set up for the track and such.

I was set to get the Torsen Tr2, but have been reading they wear and the bias becomes less efficient or doesnt work. Some of this happening just after a few track events or a season or 2 of autox. This shouldnt be happening and it doesnt seem Torsen or anyone else really does anything.

So then next up would be a locker. I am still looking at brands/types but it looks like this may be the longest lasting and strongest options.

Any advice?

Thank you in advance.

 

[shurur]

There is still the wave track (quaife) and Detroit truetrak for torque sensing differentials..

 

[9397SVTs]

I ran a Torsen T2 for 10 years in my '90 coupe that was putting 550/585 SAE to the tires. The car was a daily driver for about 7-8 years. I never experienced any problems with the Torsen. I used Redline gear oil and changed it annually. It is very quiet and smooth; you won't notice it working.

I am running a Detroit Locker in my '97 Cobra. It is putting 880/793 SAE to the tires. It works exceptionally well also. However, it is noisy and you definitely know when it is locking/unlocking.

For what you plan to use the car for, I recommend the Torsen. If you are unsure of the reliability, use the factory Traction-Lok and replace the clutches every season, or as necessary. Being a race car, more parts just become consumable. It's the cost of doing business.

 

[PaxtonShelby]

Eaton Detroit Tru-Trac and be done with it. Works well for drag and great in the twisties. Most people who go with a locker don’t like it on the street.

This is also a good time to upgrade to 31 spline, especially if you are going to put over 350 to the wheels and launch hard. I’m not even sure if the Tru Trac comes in 28 spline - you may want to check on that.

 

[Shifty Powers]

Good answers so far. To some points. I do not care about comfort. If I drive it on the street I know what I am getting into. The car will not see a drag strip

 

[Wingrider]

I have had a Torsen T2R for some time having replaced the PP dif in my 2011 GT500 set up for the track and still really like it. The car has much better/stronger off corner acceleration after it was installed.

I road course the car exclusively and track mostly at Sonoma and Laguna Seca and coach for Hooked on Driving.

 

[Coz]

The T2R as installed in the 2012-13 Boss 302, 2012-2014 GT Track Packs, and GT500 is stronger than other Torsens.

This is the commonly known as the Ford Racing M-4204-MB but the identical unit can be bought for much less if ordered from a dealer as the CR3Z-4026-A (part number forged in unit is CR3W-4206-AB.

This is also know internally to Torsen as the Torsen 975420-0200AF.

It's a 31-spline unit

 

[shurur]

Eaton Detroit Tru-Trac and be done with it. Works well for drag and great in the twisties. Most people who go with a locker don’t like it on the street.

This is also a good time to upgrade to 31 spline, especially if you are going to put over 350 to the wheels and launch hard. I’m not even sure if the Tru Trac comes in 28 spline - you may want to check on that.

It does come in a 28 spline..have one in my 99.

 

[Shifty Powers]

Went with the Trutrac - 31 spline.

We shall see how it turns out. That you all who responded

 

[98 svt]

Went with the Trutrac - 31 spline.

We shall see how it turns out. That you all who responded

I've been eyeing that as well. Where did you grab yours?

 

[Shifty Powers]

I've been eyeing that as well. Where did you grab yours?

Got it from Stranoparts.com
Hes in PA so it was easy for me. Plus the owner got on the phone and talked to me about why they have been having better luck with that vs the T2R.

One of his most recent switches is a gt500 owner who autocrosses every weekend pushing about 650 and running hoosiers. Says he has burned through 2 T2Rs already and now put in a trutrac and hasn't had any issues at all.

The torque bias is 3.1 vs the Tr2's 4.1. But its durability & being cheaper is way better.

 

[Coz]

What year GT500? Since he said it was "pushing 650" it may be a modified 5.4L GT500 that had an older design Torsen installed.

The regular T2R Torsens have a TBR of 4.1 but the OEM Torsens in the Boss and the 2013-2014 Track Pack GTs and GT500s are stronger and have a TBR of 2.7