Rear End and Gear Questions for Track and DD

[Norm Peterson]

That post is from 2009 so perhaps his opinion has changed since then? I dunno but Sam had no problem recommending the t2r to me over the phone as of a month ago but still wouldnt recomend it for fbody 10bolt diffs at that time.

Size may have something to do with it - nearly all of the 3rd/4th gen F-body cars came through with GM 10-bolt 7.5"/7.625" diffs. The 1979 Malibu that I used to autocross used the same diff. Either 26 0r 28 spline axle shafts, IIRC.


Norm

 

[Whiskey11]

Size may have something to do with it - nearly all of the 3rd/4th gen F-body cars came through with GM 10-bolt 7.5"/7.625" diffs. The 1979 Malibu that I used to autocross used the same diff. Either 26 0r 28 spline axle shafts, IIRC.


Norm

It seems to me that these failures arent necessarily case failures (although there was one in that thread) but the worm gears failing. Im not sure how much of a difference between the ten bolt GM worm gears and the 8.8 worm gears though. Either way Sam isnt the only one in that thread that had a T2R wear out. That isnt really acceptable in any differential let alone a unit costing over $700 that claims to never wear out.

 

[sheizasosay]

Maybe they got it worked out. Sam mentioned them being great for a while and then afterwards failing. Considering that he reccomends them now, he has obviously changed his mind on the part. Ask Sam to drop in.


Sent from my iPhone using Tapatalk

 

[nasty281]

not to thread jack but i was wondering if anybody had a quick suggestion on gears. since there is so many threads i didnt want to start a new one. but im about to get a 2013 5.0 m6 and wanted to know everyones preference for the manual cars that would be centrifugal s/c and daily driven 50% city 50% hwy and raced at the strip a couple times a month

 

[Napoleon85]

not to thread jack but i was wondering if anybody had a quick suggestion on gears. since there is so many threads i didnt want to start a new one. but im about to get a 2013 5.0 m6 and wanted to know everyones preference for the manual cars that would be centrifugal s/c and daily driven 50% city 50% hwy and raced at the strip a couple times a month

With a blower, probably 3.31 or 3.55. The guys over in the drag race section could probably give better feedback though ...

 

[Surfergeek]

not to thread jack but i was wondering if anybody had a quick suggestion on gears. since there is so many threads i didnt want to start a new one. but im about to get a 2013 5.0 m6 and wanted to know everyones preference for the manual cars that would be centrifugal s/c and daily driven 50% city 50% hwy and raced at the strip a couple times a month

I went through a lot before I decided on what I wanted. Tire Size, usage, and personal preference all come into play.

If you are gonna add the blower I would think about leaning towards the 3.31, especially if you think you might shorten the rear tire. (having experienced the 3.73 with and without a blower, I can tell you once I shortened the rear tires, even without the blower 1st was useless, once I added the blower 1st 2nd and 3rd could be useless if really getting on it. Making it tough to get on it in a corner without the rear end always wanting to step-out, especially with the blower.

Though I am set up for road course tracking rather than the drag strip, like the other poster said, if you want to drag race the car your gear choice may be different.

 

[nasty281]

Thanks for the input. I was initially leaning to the 3.55 b/c centrifugal blowers don't have the best torque off the bottom. But I am worried about if I would have to shift into 5th right before the stripe. Most guys with the blowers are trapping 130-135 so with 3.55s on stock tire that would probably put me into 5th

 

[Surfergeek]

So an update ...

Have had the car out with the Blower, Wavetrac, and 3.08 gears out now for 5 days on the track for road course.

It's been performing well.

Next up is an intake/tune/headers stepping away from the Ford Racing tune for the kit and dialing it in with a goal of being close to 600WHP on 91 octane.

I'll be getting a slightly taller set of tires for my next set of track tires and with with the experience driving on the 3.08 so far and learning the car am back to considering a new gear change for next season. It's all a learning experience for me, and the current ratio has been good for learning the car, and being able to get it on it a bit in the corners.

The car is no longer my every day driver and I am not as concerned about gas mileage, but what I have found is that it is happier cruising a little higher in the RPM band than the 3.08s keep it. So back to considering 3.31 or 3.55 as a final resting spot for which gears to have.

Gonna get the tune in, a couple more track days and make a decision.

So far the performance of the wavetrac has been spot on and it gets the power to the ground with ease.

 

[Bob_Kurgan]

So an update ...

Have had the car out with the Blower, Wavetrac, and 3.08 gears out now for 5 days on the track for road course.

It's been performing well.

Next up is an intake/tune/headers stepping away from the Ford Racing tune for the kit and dialing it in with a goal of being close to 600WHP on 91 octane.

I'll be getting a slightly taller set of tires for my next set of track tires and with with the experience driving on the 3.08 so far and learning the car am back to considering a new gear change for next season. It's all a learning experience for me, and the current ratio has been good for learning the car, and being able to get it on it a bit in the corners.

The car is no longer my every day driver and I am not as concerned about gas mileage, but what I have found is that it is happier cruising a little higher in the RPM band than the 3.08s keep it. So back to considering 3.31 or 3.55 as a final resting spot for which gears to have.

Gonna get the tune in, a couple more track days and make a decision.

So far the performance of the wavetrac has been spot on and it gets the power to the ground with ease.

how far are ya from GTR in Rancho Cucamunga?? Im getting on a plane and flying out there in a few hours!

 

[Surfergeek]

how far are ya from GTR in Rancho Cucamunga?? Im getting on a plane and flying out there in a few hours!

Just 5 hours or 344 miles. I am in the Northern California area in Silicon Valley.

https://maps.google.com/maps?q=ranc...gl=us&ei=xJEnUo7xLqXgiwKT7oGQDQ&ved=0CKkBELYD