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Old 08-13-2021, 08:00 AM   #7
Rory McNeil
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Join Date: Jun 2007
Location: from Vancouver BC Canada, now in Nova Scotia
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Default Re: starting line gear ratio?

What is the intended combination, and combination? With my old M/S 85 5.0 Mustang, I ran a 3.19 low gear in the Jerico, and with 4.88 gears, that made for a 15.56 SLR, and with 5.13, a 16.36 SLR. That was with 29-29 1/2" tall tires. I would have liked to have tried a bit lower rear axle ratio, but for the Ford 8.8, there was nothing between 5.13 and 5.7. Unless it is a really lightweight car with lots of power, and borderline ability to hook up, I can`t imagine a 11.25 SLR would be anywhere close to ideal. My SB Ford 4 speed G Force bracket car also has a 16.36 SLR,albeit with 31" tall tires, plus an additional 25 MPH, but looking to add a bit more rear gear ratio, or shorter tires to give another 1 or 2 hundred RPM at the 1/4 mile finish line. Same with my old hot rod type cruiser, currently has a 2.78 low Toploader with 3.50 rear and 28" tall tires, a 9.73 SLR, and I am barely hitting 4th gear at the finish line. Plus at over 4000 pounds, the organic street style clutch isn`t very happy. Hopefully the 4.33 gears (12.03 SLR) will help performance, and clutch life, at the track. And if I was to decide to switch to a modern overdrive 5 speed, I would be looking for a low gear in the 2.8 to 3.1 range.
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M/S 85 Mustang
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