Performance Rear Axel Question
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Drifting
Joined: Jun 2015
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From: Lagrange KY
Performance Rear Axel Question
Are C7’s offered with 2 different rear axel ratios? I see some offered with a “performance” rear axel 2.73 ratio while others (I think) have a 3.55 ratio. What would be the difference, not so much in top end #’s but rather in initial acceleration and also highway cruising rpm?
Last edited by Squeaky Wheel; Feb 2, 2018 at 02:56 PM.
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From: DFW Area TX
You really need to look at the overall gear ratios as the different rear ratios are on different transmissions.
Gear Ratios:
...........................A8....Z51A8.. ...MN7...Z51MN7
.........................------..------..------..------
First gear............... 4.56 .. 4.56 .. 2.66 .. 2.97
Second gear.............. 2.97 .. 2.97 .. 1.78 .. 2.07
Third gear............... 2.08 .. 2.08 .. 1.30 .. 1.43
Fourth gear.............. 1.69 .. 1.69 .. 1.00 .. 1.00
Fifth gear............... 1.27 .. 1.27 .. 0.74 .. 0.71
Sixth gear............... 1.00 .. 1.00 .. 0.50 .. 0.57
Seventh gear............. 0.85 .. 0.85 .. 0.42 .. 0.48
Eighth gear.............. 0.65 .. 0.65 .. .... .. ....
Reverse.................. 3.82 .. 3.82 .. 2.90 .. 2.90
Axle ratio............... 2.41 .. 2.73 .. 3.42 .. 3.42
Overall ratios:
...........................A8....Z51A8.. ...MN7...Z51MN7
.........................------..------..------..------
First gear...............10.99 ..12.45 .. 9.10 ..10.16
Second gear.............. 7.16 .. 8.11 .. 6.09 .. 7.08
Third gear............... 5.01 .. 5.68 .. 4.45 .. 4.89
Fourth gear.............. 4.07 .. 4.61 .. 3.42 .. 3.42
Fifth gear............... 3.06 .. 3.47 .. 2.53 .. 2.43
Sixth gear............... 2.41 .. 2.73 .. 1.71 .. 1.95
Seventh gear............. 2.05 .. 2.32 .. 1.44 .. 1.64
Eighth gear.............. 1.57 .. 1.77 .. .... .. ....
Also, the rear axle ratio is determined by which transmission and other things like Z51 or not, GS or not, etc. The axle ratio cannot be specified separately.
All C7s with the MN7 have 3.42 rear ratios.
The Grand Sport and Z06 have 2.41 rear ratio with the A8
The Z51 has 2.73 with the A8.
The base Stingray has 2.41 with the A8.
The data is different for 2014 automatics because that was the A6, not the A8.
Gear Ratios:
...........................A8....Z51A8.. ...MN7...Z51MN7
.........................------..------..------..------
First gear............... 4.56 .. 4.56 .. 2.66 .. 2.97
Second gear.............. 2.97 .. 2.97 .. 1.78 .. 2.07
Third gear............... 2.08 .. 2.08 .. 1.30 .. 1.43
Fourth gear.............. 1.69 .. 1.69 .. 1.00 .. 1.00
Fifth gear............... 1.27 .. 1.27 .. 0.74 .. 0.71
Sixth gear............... 1.00 .. 1.00 .. 0.50 .. 0.57
Seventh gear............. 0.85 .. 0.85 .. 0.42 .. 0.48
Eighth gear.............. 0.65 .. 0.65 .. .... .. ....
Reverse.................. 3.82 .. 3.82 .. 2.90 .. 2.90
Axle ratio............... 2.41 .. 2.73 .. 3.42 .. 3.42
Overall ratios:
...........................A8....Z51A8.. ...MN7...Z51MN7
.........................------..------..------..------
First gear...............10.99 ..12.45 .. 9.10 ..10.16
Second gear.............. 7.16 .. 8.11 .. 6.09 .. 7.08
Third gear............... 5.01 .. 5.68 .. 4.45 .. 4.89
Fourth gear.............. 4.07 .. 4.61 .. 3.42 .. 3.42
Fifth gear............... 3.06 .. 3.47 .. 2.53 .. 2.43
Sixth gear............... 2.41 .. 2.73 .. 1.71 .. 1.95
Seventh gear............. 2.05 .. 2.32 .. 1.44 .. 1.64
Eighth gear.............. 1.57 .. 1.77 .. .... .. ....
Also, the rear axle ratio is determined by which transmission and other things like Z51 or not, GS or not, etc. The axle ratio cannot be specified separately.
All C7s with the MN7 have 3.42 rear ratios.
The Grand Sport and Z06 have 2.41 rear ratio with the A8
The Z51 has 2.73 with the A8.
The base Stingray has 2.41 with the A8.
The data is different for 2014 automatics because that was the A6, not the A8.
Last edited by Zymurgy; Feb 2, 2018 at 03:12 PM.
