Choosing Rear gear ratios
#1
Drifting
Thread Starter
Choosing Rear gear ratios
As soon as I get the harmonic balancer straightened out I will be taking my 02 M6 in for a rear end rebuild. It's whining horribly. Since the work has to be done anyway I am thinking about going with 3.90 or 3.73 ring and pinion. I'm basically stock and I do track occasionally. Mostly I just play on the back roads. I'm told that 3.90 gears will really wake it up around town but I worry that it may ruin highway driving. As the cost is the same or close enough to it that it's irrelevant, I'm hoping for feedback form those who have done these gears.
Thanks in advance.
Thanks in advance.
#2
Drifting
I love my 4.10s. Still getting 28mpg at 70mph on the highway. I have read that those going with 3.73s or 3.90s don't feel that much of a difference.
#4
1/4 mile/AutoX
I want 4,10's bad !!! 6th is worthless below 74 mph and would be used a lot more in my car with lower gears. gears make a huge difference !!!!!
The following 2 users liked this post by Pounder:
Mike98SilVert (04-28-2017),
nsogiba (04-27-2017)
#5
I can't answer for 3.73 or 3.90 but I love the 4:10 in my Z. No issue on the highway at all. Makes 6th gear usable at 55+ MPH. My fuel mileage has suffered a few MPG but I could care less. I didn't buy a Corvette to get 30+ MPG. I would go with at least the 3.90 and consider 4.10's
#7
Drifting
Recalibration is not required for manual transmission cars. Auto only.
#9
#10
Racer
I want 4.10s, but my issue is that 2nd gear is perfect right now for autocross. I might end up limiting my top end in 2nd since first and second gears in the Z06 are already shorter.
I'm on the fence though.
I'm on the fence though.
#11
Drifting
I am running C6 wheels, which are 19x10 in the rear, with a 285/35/19 size tire.
With 3.42 factory gearing:
RPM 1st 2nd 3rd 4th 5th 6th
500 4 7 9 12 16 23
600 5 8 11 14 19 28
700 6 9 13 16 22 33
800 7 10 14 19 25 37
900 8 12 16 21 28 42
1000 9 13 18 23 32 47
1100 10 14 20 26 35 51
1200 11 16 22 28 38 56
1300 11 17 23 30 41 61
1400 12 18 25 33 44 65
1500 13 20 27 35 47 70
1600 14 21 29 37 51 75
1700 15 22 31 40 54 79
1800 16 24 32 42 57 84
1900 17 25 34 44 60 89
2000 18 26 36 47 63 93
2100 18 28 38 49 66 98
2200 19 29 40 51 69 103
2300 20 30 41 54 73 107
2400 21 31 43 56 76 112
2500 22 33 45 58 79 117
2600 23 34 47 61 82 121
2700 24 35 49 63 85 126
2800 25 37 50 65 88 131
2900 25 38 52 68 92 135
3000 26 39 54 70 95 140
3100 27 41 56 72 98 145
3200 28 42 57 75 101 149
3300 29 43 59 77 104 154
3400 30 45 61 79 107 159
3500 31 46 63 82 110 163
3600 32 47 65 84 114 168
3700 32 49 66 86 117 173
3800 33 50 68 89 120 178
3900 34 51 70 91 123 182
4000 35 52 72 93 126 187
4100 36 54 74 96 129 192
4200 37 55 75 98 133 196
4300 38 56 77 100 136 201
4400 39 58 79 103 139 206
4500 40 59 81 105 142 210
4600 40 60 83 107 145 215
4700 41 62 84 110 148 220
4800 42 63 86 112 152 224
4900 43 64 88 114 155 229
5000 44 66 90 117 158 234
5100 45 67 92 119 161 238
5200 46 68 93 121 164 243
5300 47 70 95 124 167 248
5400 47 71 97 126 170 252
5500 48 72 99 128 174 257
5600 49 73 101 131 177 262
5700 50 75 102 133 180 266
5800 51 76 104 135 183 271
5900 52 77 106 138 186 276
6000 53 79 108 140 189 280
6100 54 80 110 142 193 285
6200 54 81 111 145 196 290
6300 55 83 113 147 199 294
6400 56 84 115 149 202 299
6500 57 85 117 152 205 304
With 4.10s
RPM 1st 2nd 3rd 4th 5th 6th
500 4 5 7 10 13 19
600 4 7 9 12 16 23
700 5 8 10 14 18 27
800 6 9 12 16 21 31
900 7 10 13 18 24 35
1000 7 11 15 19 26 39
1100 8 12 16 21 29 43
1200 9 13 18 23 32 47
1300 10 14 19 25 34 51
1400 10 15 21 27 37 55
1500 11 16 22 29 39 58
1600 12 18 24 31 42 62
1700 12 19 25 33 45 66
1800 13 20 27 35 47 70
1900 14 21 28 37 50 74
2000 15 22 30 39 53 78
2100 15 23 31 41 55 82
2200 16 24 33 43 58 86
2300 17 25 34 45 61 90
2400 18 26 36 47 63 94
2500 18 27 37 49 66 97
2600 19 28 39 51 68 101
2700 20 30 40 53 71 105
2800 21 31 42 55 74 109
2900 21 32 43 57 76 113
3000 22 33 45 58 79 117
3100 23 34 46 60 82 121
3200 23 35 48 62 84 125
3300 24 36 49 64 87 129
3400 25 37 51 66 90 133
3500 26 38 52 68 92 136
3600 26 39 54 70 95 140
3700 27 41 55 72 97 144
3800 28 42 57 74 100 148
3900 29 43 58 76 103 152
4000 29 44 60 78 105 156
4100 30 45 61 80 108 160
4200 31 46 63 82 111 164
4300 31 47 64 84 113 168
4400 32 48 66 86 116 171
4500 33 49 67 88 118 175
4600 34 50 69 90 121 179
4700 34 51 70 92 124 183
4800 35 53 72 94 126 187
4900 36 54 73 95 129 191
5000 37 55 75 97 132 195
5100 37 56 76 99 134 199
5200 38 57 78 101 137 203
5300 39 58 79 103 140 207
5400 40 59 81 105 142 210
5500 40 60 82 107 145 214
5600 41 61 84 109 147 218
5700 42 62 85 111 150 222
5800 42 63 87 113 153 226
5900 43 65 88 115 155 230
6000 44 66 90 117 158 234
6100 45 67 91 119 161 238
6200 45 68 93 121 163 242
6300 46 69 94 123 166 246
6400 47 70 96 125 169 249
6500 48 71 97 127 171 253
So to answer your question, with MY tire sizes (26.85" tire diameter) RPM in 6th at 70mph will be ROUGHLY:
1500 with 3.42 gears
1800 with 4.10 gears
Nifty little calculator that spits out the data:
http://www.andysautosport.com/learni...ors/#GearRatio
I used gearing for a '98 6 Speed F-Body, the ratios are the same as the MM6 (NON Z06) T56 in the 97-04 C5. You will need to enter your own rear tire data to account for your setup, but the difference will be minimal unless you have a wildly large or small tire.
With 3.42 factory gearing:
RPM 1st 2nd 3rd 4th 5th 6th
500 4 7 9 12 16 23
600 5 8 11 14 19 28
700 6 9 13 16 22 33
800 7 10 14 19 25 37
900 8 12 16 21 28 42
1000 9 13 18 23 32 47
1100 10 14 20 26 35 51
1200 11 16 22 28 38 56
1300 11 17 23 30 41 61
1400 12 18 25 33 44 65
1500 13 20 27 35 47 70
1600 14 21 29 37 51 75
1700 15 22 31 40 54 79
1800 16 24 32 42 57 84
1900 17 25 34 44 60 89
2000 18 26 36 47 63 93
2100 18 28 38 49 66 98
2200 19 29 40 51 69 103
2300 20 30 41 54 73 107
2400 21 31 43 56 76 112
2500 22 33 45 58 79 117
2600 23 34 47 61 82 121
2700 24 35 49 63 85 126
2800 25 37 50 65 88 131
2900 25 38 52 68 92 135
3000 26 39 54 70 95 140
3100 27 41 56 72 98 145
3200 28 42 57 75 101 149
3300 29 43 59 77 104 154
3400 30 45 61 79 107 159
3500 31 46 63 82 110 163
3600 32 47 65 84 114 168
3700 32 49 66 86 117 173
3800 33 50 68 89 120 178
3900 34 51 70 91 123 182
4000 35 52 72 93 126 187
4100 36 54 74 96 129 192
4200 37 55 75 98 133 196
4300 38 56 77 100 136 201
4400 39 58 79 103 139 206
4500 40 59 81 105 142 210
4600 40 60 83 107 145 215
4700 41 62 84 110 148 220
4800 42 63 86 112 152 224
4900 43 64 88 114 155 229
5000 44 66 90 117 158 234
5100 45 67 92 119 161 238
5200 46 68 93 121 164 243
5300 47 70 95 124 167 248
5400 47 71 97 126 170 252
5500 48 72 99 128 174 257
5600 49 73 101 131 177 262
5700 50 75 102 133 180 266
5800 51 76 104 135 183 271
5900 52 77 106 138 186 276
6000 53 79 108 140 189 280
6100 54 80 110 142 193 285
6200 54 81 111 145 196 290
6300 55 83 113 147 199 294
6400 56 84 115 149 202 299
6500 57 85 117 152 205 304
With 4.10s
RPM 1st 2nd 3rd 4th 5th 6th
500 4 5 7 10 13 19
600 4 7 9 12 16 23
700 5 8 10 14 18 27
800 6 9 12 16 21 31
900 7 10 13 18 24 35
1000 7 11 15 19 26 39
1100 8 12 16 21 29 43
1200 9 13 18 23 32 47
1300 10 14 19 25 34 51
1400 10 15 21 27 37 55
1500 11 16 22 29 39 58
1600 12 18 24 31 42 62
1700 12 19 25 33 45 66
1800 13 20 27 35 47 70
1900 14 21 28 37 50 74
2000 15 22 30 39 53 78
2100 15 23 31 41 55 82
2200 16 24 33 43 58 86
2300 17 25 34 45 61 90
2400 18 26 36 47 63 94
2500 18 27 37 49 66 97
2600 19 28 39 51 68 101
2700 20 30 40 53 71 105
2800 21 31 42 55 74 109
2900 21 32 43 57 76 113
3000 22 33 45 58 79 117
3100 23 34 46 60 82 121
3200 23 35 48 62 84 125
3300 24 36 49 64 87 129
3400 25 37 51 66 90 133
3500 26 38 52 68 92 136
3600 26 39 54 70 95 140
3700 27 41 55 72 97 144
3800 28 42 57 74 100 148
3900 29 43 58 76 103 152
4000 29 44 60 78 105 156
4100 30 45 61 80 108 160
4200 31 46 63 82 111 164
4300 31 47 64 84 113 168
4400 32 48 66 86 116 171
4500 33 49 67 88 118 175
4600 34 50 69 90 121 179
4700 34 51 70 92 124 183
4800 35 53 72 94 126 187
4900 36 54 73 95 129 191
5000 37 55 75 97 132 195
5100 37 56 76 99 134 199
5200 38 57 78 101 137 203
5300 39 58 79 103 140 207
5400 40 59 81 105 142 210
5500 40 60 82 107 145 214
5600 41 61 84 109 147 218
5700 42 62 85 111 150 222
5800 42 63 87 113 153 226
5900 43 65 88 115 155 230
6000 44 66 90 117 158 234
6100 45 67 91 119 161 238
6200 45 68 93 121 163 242
6300 46 69 94 123 166 246
6400 47 70 96 125 169 249
6500 48 71 97 127 171 253
So to answer your question, with MY tire sizes (26.85" tire diameter) RPM in 6th at 70mph will be ROUGHLY:
1500 with 3.42 gears
1800 with 4.10 gears
Nifty little calculator that spits out the data:
http://www.andysautosport.com/learni...ors/#GearRatio
I used gearing for a '98 6 Speed F-Body, the ratios are the same as the MM6 (NON Z06) T56 in the 97-04 C5. You will need to enter your own rear tire data to account for your setup, but the difference will be minimal unless you have a wildly large or small tire.
Last edited by nsogiba; 04-27-2017 at 11:11 AM.
The following users liked this post:
Pounder (04-27-2017)
#12
I am running C6 wheels, which are 19x10 in the rear, with a 285/35/19 size tire.
With 3.42 factory gearing:
RPM 1st 2nd 3rd 4th 5th 6th
500 4 7 9 12 16 23
600 5 8 11 14 19 28
700 6 9 13 16 22 33
800 7 10 14 19 25 37
900 8 12 16 21 28 42
1000 9 13 18 23 32 47
1100 10 14 20 26 35 51
1200 11 16 22 28 38 56
1300 11 17 23 30 41 61
1400 12 18 25 33 44 65
1500 13 20 27 35 47 70
1600 14 21 29 37 51 75
1700 15 22 31 40 54 79
1800 16 24 32 42 57 84
1900 17 25 34 44 60 89
2000 18 26 36 47 63 93
2100 18 28 38 49 66 98
2200 19 29 40 51 69 103
2300 20 30 41 54 73 107
2400 21 31 43 56 76 112
2500 22 33 45 58 79 117
2600 23 34 47 61 82 121
2700 24 35 49 63 85 126
2800 25 37 50 65 88 131
2900 25 38 52 68 92 135
3000 26 39 54 70 95 140
3100 27 41 56 72 98 145
3200 28 42 57 75 101 149
3300 29 43 59 77 104 154
3400 30 45 61 79 107 159
3500 31 46 63 82 110 163
3600 32 47 65 84 114 168
3700 32 49 66 86 117 173
3800 33 50 68 89 120 178
3900 34 51 70 91 123 182
4000 35 52 72 93 126 187
4100 36 54 74 96 129 192
4200 37 55 75 98 133 196
4300 38 56 77 100 136 201
4400 39 58 79 103 139 206
4500 40 59 81 105 142 210
4600 40 60 83 107 145 215
4700 41 62 84 110 148 220
4800 42 63 86 112 152 224
4900 43 64 88 114 155 229
5000 44 66 90 117 158 234
5100 45 67 92 119 161 238
5200 46 68 93 121 164 243
5300 47 70 95 124 167 248
5400 47 71 97 126 170 252
5500 48 72 99 128 174 257
5600 49 73 101 131 177 262
5700 50 75 102 133 180 266
5800 51 76 104 135 183 271
5900 52 77 106 138 186 276
6000 53 79 108 140 189 280
6100 54 80 110 142 193 285
6200 54 81 111 145 196 290
6300 55 83 113 147 199 294
6400 56 84 115 149 202 299
6500 57 85 117 152 205 304
With 4.10s
RPM 1st 2nd 3rd 4th 5th 6th
500 4 5 7 10 13 19
600 4 7 9 12 16 23
700 5 8 10 14 18 27
800 6 9 12 16 21 31
900 7 10 13 18 24 35
1000 7 11 15 19 26 39
1100 8 12 16 21 29 43
1200 9 13 18 23 32 47
1300 10 14 19 25 34 51
1400 10 15 21 27 37 55
1500 11 16 22 29 39 58
1600 12 18 24 31 42 62
1700 12 19 25 33 45 66
1800 13 20 27 35 47 70
1900 14 21 28 37 50 74
2000 15 22 30 39 53 78
2100 15 23 31 41 55 82
2200 16 24 33 43 58 86
2300 17 25 34 45 61 90
2400 18 26 36 47 63 94
2500 18 27 37 49 66 97
2600 19 28 39 51 68 101
2700 20 30 40 53 71 105
2800 21 31 42 55 74 109
2900 21 32 43 57 76 113
3000 22 33 45 58 79 117
3100 23 34 46 60 82 121
3200 23 35 48 62 84 125
3300 24 36 49 64 87 129
3400 25 37 51 66 90 133
3500 26 38 52 68 92 136
3600 26 39 54 70 95 140
3700 27 41 55 72 97 144
3800 28 42 57 74 100 148
3900 29 43 58 76 103 152
4000 29 44 60 78 105 156
4100 30 45 61 80 108 160
4200 31 46 63 82 111 164
4300 31 47 64 84 113 168
4400 32 48 66 86 116 171
4500 33 49 67 88 118 175
4600 34 50 69 90 121 179
4700 34 51 70 92 124 183
4800 35 53 72 94 126 187
4900 36 54 73 95 129 191
5000 37 55 75 97 132 195
5100 37 56 76 99 134 199
5200 38 57 78 101 137 203
5300 39 58 79 103 140 207
5400 40 59 81 105 142 210
5500 40 60 82 107 145 214
5600 41 61 84 109 147 218
5700 42 62 85 111 150 222
5800 42 63 87 113 153 226
5900 43 65 88 115 155 230
6000 44 66 90 117 158 234
6100 45 67 91 119 161 238
6200 45 68 93 121 163 242
6300 46 69 94 123 166 246
6400 47 70 96 125 169 249
6500 48 71 97 127 171 253
So to answer your question, with MY tire sizes (26.85" tire diameter) RPM in 6th at 70mph will be ROUGHLY:
1500 with 3.42 gears
1800 with 4.10 gears
Nifty little calculator that spits out the data:
http://www.andysautosport.com/learni...ors/#GearRatio
I used gearing for a '98 6 Speed F-Body, the ratios are the same as the MM6 (NON Z06) T56 in the 97-04 C5. You will need to enter your own rear tire data to account for your setup, but the difference will be minimal unless you have a wildly large or small tire.
With 3.42 factory gearing:
RPM 1st 2nd 3rd 4th 5th 6th
500 4 7 9 12 16 23
600 5 8 11 14 19 28
700 6 9 13 16 22 33
800 7 10 14 19 25 37
900 8 12 16 21 28 42
1000 9 13 18 23 32 47
1100 10 14 20 26 35 51
1200 11 16 22 28 38 56
1300 11 17 23 30 41 61
1400 12 18 25 33 44 65
1500 13 20 27 35 47 70
1600 14 21 29 37 51 75
1700 15 22 31 40 54 79
1800 16 24 32 42 57 84
1900 17 25 34 44 60 89
2000 18 26 36 47 63 93
2100 18 28 38 49 66 98
2200 19 29 40 51 69 103
2300 20 30 41 54 73 107
2400 21 31 43 56 76 112
2500 22 33 45 58 79 117
2600 23 34 47 61 82 121
2700 24 35 49 63 85 126
2800 25 37 50 65 88 131
2900 25 38 52 68 92 135
3000 26 39 54 70 95 140
3100 27 41 56 72 98 145
3200 28 42 57 75 101 149
3300 29 43 59 77 104 154
3400 30 45 61 79 107 159
3500 31 46 63 82 110 163
3600 32 47 65 84 114 168
3700 32 49 66 86 117 173
3800 33 50 68 89 120 178
3900 34 51 70 91 123 182
4000 35 52 72 93 126 187
4100 36 54 74 96 129 192
4200 37 55 75 98 133 196
4300 38 56 77 100 136 201
4400 39 58 79 103 139 206
4500 40 59 81 105 142 210
4600 40 60 83 107 145 215
4700 41 62 84 110 148 220
4800 42 63 86 112 152 224
4900 43 64 88 114 155 229
5000 44 66 90 117 158 234
5100 45 67 92 119 161 238
5200 46 68 93 121 164 243
5300 47 70 95 124 167 248
5400 47 71 97 126 170 252
5500 48 72 99 128 174 257
5600 49 73 101 131 177 262
5700 50 75 102 133 180 266
5800 51 76 104 135 183 271
5900 52 77 106 138 186 276
6000 53 79 108 140 189 280
6100 54 80 110 142 193 285
6200 54 81 111 145 196 290
6300 55 83 113 147 199 294
6400 56 84 115 149 202 299
6500 57 85 117 152 205 304
With 4.10s
RPM 1st 2nd 3rd 4th 5th 6th
500 4 5 7 10 13 19
600 4 7 9 12 16 23
700 5 8 10 14 18 27
800 6 9 12 16 21 31
900 7 10 13 18 24 35
1000 7 11 15 19 26 39
1100 8 12 16 21 29 43
1200 9 13 18 23 32 47
1300 10 14 19 25 34 51
1400 10 15 21 27 37 55
1500 11 16 22 29 39 58
1600 12 18 24 31 42 62
1700 12 19 25 33 45 66
1800 13 20 27 35 47 70
1900 14 21 28 37 50 74
2000 15 22 30 39 53 78
2100 15 23 31 41 55 82
2200 16 24 33 43 58 86
2300 17 25 34 45 61 90
2400 18 26 36 47 63 94
2500 18 27 37 49 66 97
2600 19 28 39 51 68 101
2700 20 30 40 53 71 105
2800 21 31 42 55 74 109
2900 21 32 43 57 76 113
3000 22 33 45 58 79 117
3100 23 34 46 60 82 121
3200 23 35 48 62 84 125
3300 24 36 49 64 87 129
3400 25 37 51 66 90 133
3500 26 38 52 68 92 136
3600 26 39 54 70 95 140
3700 27 41 55 72 97 144
3800 28 42 57 74 100 148
3900 29 43 58 76 103 152
4000 29 44 60 78 105 156
4100 30 45 61 80 108 160
4200 31 46 63 82 111 164
4300 31 47 64 84 113 168
4400 32 48 66 86 116 171
4500 33 49 67 88 118 175
4600 34 50 69 90 121 179
4700 34 51 70 92 124 183
4800 35 53 72 94 126 187
4900 36 54 73 95 129 191
5000 37 55 75 97 132 195
5100 37 56 76 99 134 199
5200 38 57 78 101 137 203
5300 39 58 79 103 140 207
5400 40 59 81 105 142 210
5500 40 60 82 107 145 214
5600 41 61 84 109 147 218
5700 42 62 85 111 150 222
5800 42 63 87 113 153 226
5900 43 65 88 115 155 230
6000 44 66 90 117 158 234
6100 45 67 91 119 161 238
6200 45 68 93 121 163 242
6300 46 69 94 123 166 246
6400 47 70 96 125 169 249
6500 48 71 97 127 171 253
So to answer your question, with MY tire sizes (26.85" tire diameter) RPM in 6th at 70mph will be ROUGHLY:
1500 with 3.42 gears
1800 with 4.10 gears
Nifty little calculator that spits out the data:
http://www.andysautosport.com/learni...ors/#GearRatio
I used gearing for a '98 6 Speed F-Body, the ratios are the same as the MM6 (NON Z06) T56 in the 97-04 C5. You will need to enter your own rear tire data to account for your setup, but the difference will be minimal unless you have a wildly large or small tire.
So basically it's a 300 RPM difference...how much of a difference did it make acceleration wise? Enough that you can feel it?
#13
Drifting
You can definitely feel it. But, I took apart my car in December with the 3.42s and got it back on the road in March with 4.10s, so my butt dyno became somewhat uncalibrated over 3 months of not driving it.
#15
1/4 mile/AutoX
#16
Le Mans Master
Pro Mechanic
I've given this some thought myself...beyond the cost, my only worry about changing the rear-end gears is introducing a problem where I don't have one now (factory gears, no leaks, no whining, etc.). Kinda the if it ain't broke don't fix it thing. But, for sure, if I ever do pull the trigger it would be 4.10's...only 300 rpm more at 70? That's nuthin'...
#17
1/4 mile/AutoX
I've given this some thought myself...beyond the cost, my only worry about changing the rear-end gears is introducing a problem where I don't have one now (factory gears, no leaks, no whining, etc.). Kinda the if it ain't broke don't fix it thing. But, for sure, if I ever do pull the trigger it would be 4.10's...only 300 rpm more at 70? That's nuthin'...
#18
Drifting
I've given this some thought myself...beyond the cost, my only worry about changing the rear-end gears is introducing a problem where I don't have one now (factory gears, no leaks, no whining, etc.). Kinda the if it ain't broke don't fix it thing. But, for sure, if I ever do pull the trigger it would be 4.10's...only 300 rpm more at 70? That's nuthin'...
After installing my 4.10s I have a very small whine, but it could be that I rebuilt my T56 myself and maybe screwed something up. It's really not noticeable unless you have the windows up and radio off. Usually I have the windows down, radio up, and exhaust screaming...you tend to forget very quickly about any minor issue like that.
I would gladly take a tiny bit of whine from 4.10s over the bucking, surging, and smell that comes with a Heads/Cam setup that produces similar performance results to a gear install.
#19
following this
#20
Safety Car
Don't mess with it
This black Z ( a good friends ride ) with 550 RWHP AND 410s ( No power adders ) with 345 tires at Royal Purple drag strip in Bay Town TX. spin for 1/4 mile and still ran a 10/36 and just last week on a rolling start smoked brand new Z pulling away the whole time never seen him .. He says the 410s are the deal .. Al I know is that C-6 Z is one fast Hot rod..