Rear diff ratio question
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Melting Slicks
Joined: Feb 2015
Posts: 2,122
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From: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
Rear diff ratio question
I'm thinking about trying a different rear gear in my c6 race car. The idea is to eliminate the need to shift into 5th.on the long straights. Unfortunately, I'm racing against those with the new sequential trans, and shifting my old gear box simply takes too much time and 5th is way too high. I currently have a 3.42 rear ratio. To go much lower (3.15 pr 2.73) appears I may need to go with an automatic unit, or can i have those ratios installed in a standard rear diff that are available?
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I'm thinking about trying a different rear gear in my c6 race car. The idea is to eliminate the need to shift into 5th.on the long straights. Unfortunately, I'm racing against those with the new sequential trans, and shifting my old gear box simply takes too much time and 5th is way too high. I currently have a 3.42 rear ratio. To go much lower (3.15 pr 2.73) appears I may need to go with an automatic unit, or can i have those ratios installed in a standard rear diff that are available?
Thread Starter
Melting Slicks
Joined: Feb 2015
Posts: 2,122
Likes: 452
From: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
My race car was built based on the steel chassis therefore the current rear diff is a standard C6 which with fluids being pumped to keep it cool has worked well over the last 4 years. Will any auto rear diff still bolt up and I assume the splines would be the same as mine also as the Z06 are larger? I read somewhere that the 3:15 ratio was a performance option in auto cars is that true?
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From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11-'12, '14-'15-'16-'17-'18
My race car was built based on the steel chassis therefore the current rear diff is a standard C6 which with fluids being pumped to keep it cool has worked well over the last 4 years. Will any auto rear diff still bolt up and I assume the splines would be the same as mine also as the Z06 are larger? I read somewhere that the 3:15 ratio was a performance option in auto cars is that true?
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Thread Starter
Melting Slicks
Joined: Feb 2015
Posts: 2,122
Likes: 452
From: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
Thanks for the info! My trans/diff is a 2008 forgot to mention, not sure if that makes a difference, so a 97 C5 and up to only a 2005 C6 auto rear diff accepts that tail shaft. If the newer 06 and up 315 Auto diffs have a larger spline, can they be changed out with my 3.42 diff spline internally? Trying to confirm all before i buy one that doesn't work.
Thread Starter
Melting Slicks
Joined: Feb 2015
Posts: 2,122
Likes: 452
From: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
Supporting Vendor
Joined: Apr 2011
Posts: 3,332
Likes: 195
From: Frederick Maryland
St. Jude Donor '08-'09-'10-'11-'12, '14-'15-'16-'17-'18
Thanks for the info! My trans/diff is a 2008 forgot to mention, not sure if that makes a difference, so a 97 C5 and up to only a 2005 C6 auto rear diff accepts that tail shaft. If the newer 06 and up 315 Auto diffs have a larger spline, can they be changed out with my 3.42 diff spline internally? Trying to confirm all before i buy one that doesn't work.
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