Which diff to go with?

[Madlock]

I've been weighing adding a Torsen differential to my 2011 Coupe. There are 3 ways I can go.

 

I can add a T-2 or T-2R to the existing OE differential - with the additional option of increasing the final drive ratio to with a new ring and pinion set to 4.10 or even 4.30 (I basically never use first gear anymore anyway).

 

I can also purchase a complete, sealed differential with a Torsen T-2 and 3.73 gearing and swap-out the entire differential on a sealed-unit basis. The cost difference between the T-2 and T-2R is about $130.00. The entire sealed differential assembly (with T-2 made for BOSS 302) is only about $200 more.

 

Am I better-off leaving the gearing alone and forgoing the additional benefit of a T-2R and investing $300 more to have a sealed-unit swap-out that's likely to be bang down the center on tolerances?

[DOGEMAN223]

I've been weighing adding a Torsen differential to my 2011 Coupe. There are 3 ways I can go.

 

I can add a T-2 or T-2R to the existing OE differential - with the additional option of increasing the final drive ratio to with a new ring and pinion set to 4.10 or even 4.30 (I basically never use first gear anymore anyway).

 

I can also purchase a complete, sealed differential with a Torsen T-2 and 3.73 gearing and swap-out the entire differential on a sealed-unit basis. The cost difference between the T-2 and T-2R is about $130.00. The entire sealed differential assembly (with T-2 made for BOSS 302) is only about $200 more.

 

Am I better-off leaving the gearing alone and forgoing the additional benefit of a T-2R and investing $300 more to have a sealed-unit swap-out that's likely to be bang down the center on tolerances?

 

So how much is complete rearend with Torsen?

thanks

[08 ORANGE SS-725HP]

What are you trying to accomplish with your car?? You already have 3.73's with a traction lock. Why are you looking to change to a T2R diff and even considering 4.10's or 4.30's?? Before you even answer those questions I'm inclined to tell you to keep your money in your pocket and drive the car the way it is. It will perform fine the way it is on the street, road race course, and drag strip.

[Madlock]

What are you trying to accomplish with your car?? You already have 3.73's with a traction lock. Why are you looking to change to a T2R diff and even considering 4.10's or 4.30's?? Before you even answer those questions I'm inclined to tell you to keep your money in your pocket and drive the car the way it is. It will perform fine the way it is on the street, road race course, and drag strip.

 

 

I want to improve turns at speed, which a T-2 should most certainly do. The T-2R would be an excellent value opportunity given its nominal incremental cost over the T-2, and the fact that it would always have friction to transfer, be there wheel contact or not.

 

Gearing would be for the very specific purpose of better suiting the rev range to drivable gears. There's simply too much torque to make first useful with a 3.73, so I invariably start from second, also eliminating a shift on my way to 1:1 direct drive in 4th. Furthermore, 5th and 6th in the TR-6060 are taller in GT500 than the standard transmission for economy's sake, and at the expense of performance. Going to a 2-6 shift regimen with a 4.30 gearing and a nominally-smaller rear wheel diameter may very well result in a car that performs more as I prefer - if the math and power band I've mapped out hold true.

[08 ORANGE SS-725HP]

I want to improve turns at speed, which a T-2 should most certainly do. The T-2R would be an excellent value opportunity given its nominal incremental cost over the T-2, and the fact that it would always have friction to transfer, be there wheel contact or not.

 

Gearing would be for the very specific purpose of better suiting the rev range to drivable gears. There's simply too much torque to make first useful with a 3.73, so I invariably start from second, also eliminating a shift on my way to 1:1 direct drive in 4th. Furthermore, 5th and 6th in the TR-6060 are taller in GT500 than the standard transmission for economy's sake, and at the expense of performance. Going to a 2-6 shift regimen with a 4.30 gearing and a nominally-smaller rear wheel diameter may very well result in a car that performs more as I prefer - if the math and power band I've mapped out hold true.

 

Wow-no flame intended but with your reasoning bro there's no good advice I could give you!

[BDrool]

What are you trying to accomplish with your car?? You already have 3.73's with a traction lock. Why are you looking to change to a T2R diff and even considering 4.10's or 4.30's?? Before you even answer those questions I'm inclined to tell you to keep your money in your pocket and drive the car the way it is. It will perform fine the way it is on the street, road race course, and drag strip.

 

 

 

Just so you know, probably just terminology, the GT500 has a limited slip diff. A traction lock diff would be a great improvement which is what the torsen does. The question that has been brought up is will the Torsen hold up with constant dropping of the clutch. Also, no matter what you do, the limited slip clutch packs will have to be replaced, repeatedly. They wear out, just the nature of the design. The Torsen, I believe, will get you away from the clutch replacement issue.

[TrakRat]

I believe Madlock is trying to relieve the one wheel-itis that these cars get with the factory LSD even in street driving. When accelerating out of a turn without full power available to BOTH wheels in a predictable manner it is very difficult to get repeatable and confident handling out of the car. I like the idea personally.

 

I don't have much to say about the gear swap other than the .50 6th gear is pretty steep, and a shorter gear may help eliminate a bit of lugging.

[Madlock]

Wow-no flame intended but with your reasoning bro there's no good advice I could give you!

 

No sweat. Keep practicing - I'm sure you'll do better next time.

[JWG223]

I have had gears put in cars, etc. and I would get the sealed unit, because if this thing whines, you won't like it I don't think. On a $50-60K car, I sure wouldn't!

[socalwrench]

Well, you're already on the right track with the Torsen- it's the best LSD for the street IMO; much better than any clutch type LSD. Stepping up to the T2R should change the torque bias, but I don't think it's necessary. Honestly, I would buy the car with the T2 (I'm assuming it's an option still) and 3.73s first, and see how the car drives. Real world variables always seem to change the equation a bit, such as tire slippage, tire temp., track temp., track surface type, track elevation changes, and clutch slippage.

[Madlock]

I have had gears put in cars, etc. and I would get the sealed unit, because if this thing whines, you won't like it I don't think. On a $50-60K car, I sure wouldn't!

 

 

That's what makes the sealed unit such a nice fall-back position. Knowing ring and pinion swaps are as much art as science, always having the option to throw-in the sealed unit (WITH a T-2) for <$1,500 is one hell of a fall-back position.

 

Well, you're already on the right track with the Torsen- it's the best LSD for the street IMO; much better than any clutch type LSD. Stepping up to the T2R should change the torque bias, but I don't think it's necessary. Honestly, I would buy the car with the T2 (I'm assuming it's an option still) and 3.73s first, and see how the car drives. Real world variables always seem to change the equation a bit, such as tire slippage, tire temp., track temp., track surface type, track elevation changes, and clutch slippage.

 

That's what I've been thinking. And it's a damn cost-effective improvement for the kind of benefit potential it delivers. I realize the T-2R COULD change the torque bias, but unless the change would be negative, it's hard to scoff at for the extra $130 or so - being the same unit the FR500C uses.