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T2R vs. T2R

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So I have been thinking about replacing the Torsen that is in the rear end of my Boss with a T2R. Now I found 2 options for these. One being the Ford Racing FR500S unit that is used in the FR500S/Boss 302S/Boss 302R, and the second one is the one that Maximum Motorsports sells. That being said they are both 31 spline and they both have a 4:1 bias ratio. They appear to be thar same but I'm not certain if there are any differences between the two that would make one better than the other


Does anyone know what the differences are if any?
 

TymeSlayer

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Am interested as well.

Also, for those of us who did not get the Torsen option, what did they put in there? What's the base part number too if you have it.
 
I run the T2R and have had no issues. I went with the Ford racing unit. I am sure The MMS unit is the exact same unit without the Ford shipping container. I would call them and ask. At the time I built my car, I wasn't aware there was an OEM option for the unit, otherwise, I would have gone that route.
 
I am leaning towards the Ford Racing unit due to the fact that it is used on their race cars, but I'm still curious about the MM unit as they make some high quality things and I would image their Torsen is built to the same standards. The price difference between the two is something like $20 or $30 so I don't really care about the pricing aspect. Anyway, here is MM response.

Mr. Wright,

The Torsen differentials that FRPP sells and the models that we sell are not the same.

The Torsen differentials are customized to Ford's requirements for instance. You'll have to compare the specifications on each
website to see what the differences are.

The T2R we sell has a higher TBR than the True-Trac. This is important in any situation where there is a lot of lateral weight
transfer. If the car corners hard enough to end up with a 80% of its weight on the outside rear tire and 20% of its weight on the
inside rear tire, then the differential needs a TBR of at least 4:1 (80%/20%). This is so it can delivery 80% of the engine torque
to the outside tire which has much more weight on it for more potential traction. If the TBR in this case was only 3:1, then the
differential would send 33% of the driveshaft torque to the inside tire which would result in its spinning while the outside tire
still had excess torque capacity. The T2R has the highest TBR of any aftermarket differential. For autox use, where there is very
high lateral weight transfer this is very important. The more cornering grip is available, the more weight transfer and the more
important having a high TBR is.

As a torque biasing differentials wears, the TBR decreases some. So its better to start out with a TBR that is higher than may be
needed when in doubt.

The only application where I've ever seen a Torsen break is in drag racing. We've used them in ever Mustang we have here and never
broken one. We don't drag race any of the cars, but we have done plenty of 0-60mph testing for various uses, but never on slicks.

I did ask them about the Tru-Trac since I have been told to just go with that since it is cheaper but for the $100 I think I would rather go with the T2R and the higher bias ratio. I guess I will have to get in touch with Ford Racing and see if they know what the difference is between the two. I doubt they would though.
 
They are the same according to Torsen website
http://torsen.info/distributors/Ford_distributors.htm

Ford 8.8" Torsen® T-2 & T-2R Differentials:
Torsen P/N 409200-0204G (31 Tooth) = M-4204-T31
Torsen P/N 409200-0204H (28 Tooth) = M-4204-T28
Torsen P/N 409000-2170 (31 Tooth) = M-4024-MB (1)
Torsen P/N 975420-0200L (31 Tooth) = M-4202-T31H
MTX75 Torsen T-2 Ford Focus Differential:
Torsen P/N 975420-0208A (26 Tooth) = M-4204-F20
SVT Focus Torsen T-2 Differential:
Torsen P/N 975420-0209B (34 Tooth) = M-4204-FSVT
Ford Racing Performance Parts (FRPP)
44050 North Groesbeck Highway, Clinton Township, MI 48036
Tel: (810) 468-1356

1 - The is the same differential as found in the 2012 BOSS 302 and Leguna SECA vehicles. You can only purchase this unit from a Ford Dealership or the Ford Racing Parts website.

Ford 8.8" Torsen® T-2R (28 & 31 Spline) High Bias Differential:
Torsen P/N 975420-0200L (31 Tooth) = TOR-F88ZT31HBI[/color]
Torsen P/N 975420-0200M (28 Tooth) = TOR-F88ZT28HBI
Maximum Motorsports, Inc.
3430 Sacramento Drive, Unit D
San Luis Obispo, CA 93401
Tel: (888) 378-8830

You can also find the difference between the other version of the Torsen on the website. Like the one that stock on the Boss
 

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