Need A Beffier Irs Differential
Race Director
Joined: Jan 2000
Posts: 13,018
Likes: 2,262
From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
C2 of Year Winner (performance mods) 2019
2017 C2 of Year Finalist
Tom's Differentials. Pretty much the main folks messing with them.
Lots of 8 and 9 sec Vette's with them.
JIM
Lots of 8 and 9 sec Vette's with them.
JIM
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Mine isn't from Tom's, but I can attest that an Eaton based 12-bolt IRS diff conversion is the way to go. I'd upgrade your half-shafts at least to factory 3" pieces, and make sure to run solid Spicer U's, too.
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
Thanks,
ltlevil
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
I could probably adjust that out and put it to use on certain courses, but the 4.11:1 proved too deep for the street and I'm not that into parking lot variety auto-Xing. The one currently in my SA was done by Henry's Machine Works using an Eaton posi and 3.55. I can't recall a name, as it's been about 20 years, but the guy who used to do Muldowney's diffs set it up. I've broken and upgraded other stuff since, but the diff has proved bullet proof. If I ever have to let go of my SA, this piece stays with me.
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
My first one was done by a local shop (long since gone) in Memphis using a tight Moroso posi. While it was fine in a straight line, the instability caused by ratcheting when trying to put power down in fast sweepers was undesirable, to say the least. I could probably adjust that out and put it to use on certain courses, but the 4.11:1 proved too deep for the street and I'm not that into parking lot variety auto-Xing.
The one currently in my SA was done by Henry's Machine Works using an Eaton posi and 3.55. I can't recall a name, as it's been about 20 years, but the guy who used to do Muldowney's diffs set it up. I've broken and upgraded other stuff since, but the diff has proved bullet proof. If I ever have to let go of my SA, this piece stays with me.
I could probably adjust that out and put it to use on certain courses, but the 4.11:1 proved too deep for the street and I'm not that into parking lot variety auto-Xing. The one currently in my SA was done by Henry's Machine Works using an Eaton posi and 3.55. I can't recall a name, as it's been about 20 years, but the guy who used to do Muldowney's diffs set it up. I've broken and upgraded other stuff since, but the diff has proved bullet proof. If I ever have to let go of my SA, this piece stays with me.
Can't blame you for wanting to keep it. Thanks for the info.
Steve
Team Owner
Joined: Nov 2004
Posts: 20,715
Likes: 25
From: Sorrento Italy
Just my personal experience.
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