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Old 03-27-2017, 12:32 PM
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gnx7 gnx7 is offline
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This is a great gear ratio calculator:
http://fitbodyshop.net/gear/index.php

I love the close ratio 5speed TUET11009 with .63 overdrive. Select CTSv Gen2 on that calculator for these ratios. Otherwise just input the gearing manually. The gearing is just about perfect as you can see by the graph and chart. A little more overdrive would be nice... one rarely uses 5th gear on a road course anyway and 1-4 are awesome ratios.

Quote:
Originally Posted by SlowProgress View Post
I probably thought about it way too much. I knew I wanted a new Magnum for strength and I was already planning to cut the tunnel for easy of service. I loved driving the car with the Muncie for so many years (with 4.56 gears) that I figured it would be fun to pick a transmission and rear ratio somewhat close to the original gear ratios. I know it is weird but I used to enjoy starting in second and then just shifting straight to fourth with the deep rear ratio. I built a little gear calculator and messed around with the numbers.
The wide ratio (TUET11012) first four gears lined up closest to the original Muncie wide ratio gear ratios, coupled with the new 3.90 rear gear.

Then I looked at highway speeds and figured I want to cruise the heck out of this car and the roads are long and straight out here in the west. It was easy to select the wide ratio with the .5 final ratio to keep the RPM below 2,000 at 75 MPH.
If the car runs out a steam too early on the Auto-X then I can always select a higher gear ratio like 3.70 or 3.5.

__________________
Project: 1969 Chevelle, alum 5.3, GTS76 turbo, Chiseled Perf A/W intercooler, Holley Dominator EFI, Davis TC, JRi coilovers, 14" brakes, T56 Magnum. CTS-V Recaro seats!
Coffey Fabrication Nashville, TN doing the fabwork! 800rwhp+/25mpg+/9's@150mph goal
https://lateral-g.net/forums/showthread.php4?t=52976

1993 Mazda FD RX-7, built LS7, T56 Magnum, Holley HP, Davis Tech TC, 8.8" 3.73 Cobra IRS diff, DSS axles, Ohlins coilovers, big brakes.
CCW 18x11 front 315/30/18's and 18x12.5 rear on 335/30/18 RA1's, 2850lbs
10.31@137mph 165mph Shift-Sector 1/2 mile speed
441ci AllPro headed motor and 200lb weigh reduction in the works....
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