1986 4+3-- Max Speed Per Gear??
03-16-2019, 04:37 PM
#1
Heel & Toe
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1986 4+3-- Max Speed Per Gear??
Hey so I was curious if anyone had the chart that shows what the max speed at redline in each gear is for the 4+3 C4. I have looked my damn butt off and can't find it anywhere online so if anyone knows id appreciate it! Thanks in advance, because this information has been really difficult to find.
03-17-2019, 11:56 AM
#4
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Try this site. From those numbers you can gen. a table of speed at redline in each gear.
Looks like 3.07 was the only diff. ratio for the 4+3 in '86.
For example my '89 MN6 in 4th gear (1.00:1) with the 3.07 diff. runs 137mph @5,500rpm.
Looks like 3.07 was the only diff. ratio for the 4+3 in '86.
For example my '89 MN6 in 4th gear (1.00:1) with the 3.07 diff. runs 137mph @5,500rpm.
03-17-2019, 03:08 PM
#5
Melting Slicks
Here's a handy gear chart/calculator:
http://www.pszweb.com/car/gears.htm
Suggest 798 revs/mile for 255/50R16 tire or 811 revs/mile for 275/40R17 tire. Also need to know which O/D ratio: MH5 0.62 or MK2 0.68. Assume 3.07 rear.
If you want to determine mph for each gear with O/D active, you need to do a little math (multiply the gear ratio by the O/D ratio first) and input the overall ratios into the various gear slots.
http://www.pszweb.com/car/gears.htm
Suggest 798 revs/mile for 255/50R16 tire or 811 revs/mile for 275/40R17 tire. Also need to know which O/D ratio: MH5 0.62 or MK2 0.68. Assume 3.07 rear.
If you want to determine mph for each gear with O/D active, you need to do a little math (multiply the gear ratio by the O/D ratio first) and input the overall ratios into the various gear slots.
03-21-2019, 07:01 AM
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IDK , so truly curious: WILL the stock L98 pull to 137mph in 4th WITHOUT OD? The stock torque curve for the L98 is precipitous beyond 4200 rpm and after 4500 it's just making noise ... no? No doubt 150 in OD may be possible. But, 137 in 4th @ 5500 rpm...surprises me (a little).
03-21-2019, 09:36 AM
#7
Melting Slicks
Use the chart.
With a standard size tire 275/40R17 (811 rev/mile): an 89 MN6 w-3.07 gear will reach 133 mph at 5500 rpm in 4th gear, 122 mph w-3.33 gear and 115 mph w-3.54 gear (assuming it has the power to get there in each case).
137 mph would require a taller tire ~784 rev/mile. For example a 275/30R20 tire would be in the ballpark, but this is not a typical size for a C4.
With a standard size tire 275/40R17 (811 rev/mile): an 89 MN6 w-3.07 gear will reach 133 mph at 5500 rpm in 4th gear, 122 mph w-3.33 gear and 115 mph w-3.54 gear (assuming it has the power to get there in each case).
137 mph would require a taller tire ~784 rev/mile. For example a 275/30R20 tire would be in the ballpark, but this is not a typical size for a C4.
03-22-2019, 10:43 AM
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Use the chart.
With a standard size tire 275/40R17 (811 rev/mile): an 89 MN6 w-3.07 gear will reach 133 mph at 5500 rpm in 4th gear, 122 mph w-3.33 gear and 115 mph w-3.54 gear
137 mph would require a taller tire ~784 rev/mile. For example a 275/30R20 tire would be in the ballpark, but this is not a typical size for a C4.
With a standard size tire 275/40R17 (811 rev/mile): an 89 MN6 w-3.07 gear will reach 133 mph at 5500 rpm in 4th gear, 122 mph w-3.33 gear and 115 mph w-3.54 gear
137 mph would require a taller tire ~784 rev/mile. For example a 275/30R20 tire would be in the ballpark, but this is not a typical size for a C4.
NOTE: The scale on the graph is arranged in 800 rpm increments between reference points except for the last one which is only 400 rpm. IF the graph was extended to 5500 rpm AND the scale reflected 800 rpm increments, it would show the L98 having NO practical "omph" at 5500...if it would even push the car enough to overcome road resistance. Gonna need a taller gear to convert some of that marvelous L98 low-end grunt into mph!
03-23-2019, 09:50 AM
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St. Jude Donor '05
Try driving it, different story.