I know it sounds crazy and insane, but with the super low 4.17 1st gear in the 6R80, and the available power with a "built" Coyote equipped with a power adder, it would seem feasable to start out in 2nd gear, possibly in a race tune file just for the track with low rear differential gearing.
A little help with a gear calculator says that a 6R80 in second (2.34:1) on a 28.2" tall tire would be at 58mph at 7K rpm's with 4.30 gears
With the same tire at the same rpm with a T56 in 1st (2.66:1) gear you'd be going 59mph with 3.73's
With the same tire, at the same rpm with a C4 in 1st (2.46:1) gear you'd be going 58mph with 4.10's
With the same tire, at the same rpm with a power-glide in 1st (1.82:1) gear you'd be over 70mph with 4.56's
I just did the other transmission ratios to kind of validate that a 2nd gear start with a 6R80 isn't all that crazy when considering the ratios of other transmissions. It might be something to consider if you're going through 1st gear in a 6R80 so damn quickly that it's tough to get a good up-shift point established in the tune especially with a very powerful car. Also with todays technology, making a boat-load of power with a Coyote is being done alot, and rear gears dipping below the stock 3.15 ratio aren't the easiest thing to come by for an 8.8.
If I was to build my Motor some day and boost it up to have over 750 or more hp to the wheels I think I'd at least try doing something like this before ditching my nice overdriven 6R80 and going to a non OD C4, TH400, or powerglide, and I'd think it would be alot less finicky to launch and tune for the shift points than simply staying with the 3.15 rear gears, and running up to a 30" tall tire?? Also with 4.30 gears @80mph, you'd still be under 3K in 6th gear with a 28.2" tire, if you was worried about the highway driving capabilities of the lower rear gears.
A little help with a gear calculator says that a 6R80 in second (2.34:1) on a 28.2" tall tire would be at 58mph at 7K rpm's with 4.30 gears
With the same tire at the same rpm with a T56 in 1st (2.66:1) gear you'd be going 59mph with 3.73's
With the same tire, at the same rpm with a C4 in 1st (2.46:1) gear you'd be going 58mph with 4.10's
With the same tire, at the same rpm with a power-glide in 1st (1.82:1) gear you'd be over 70mph with 4.56's
I just did the other transmission ratios to kind of validate that a 2nd gear start with a 6R80 isn't all that crazy when considering the ratios of other transmissions. It might be something to consider if you're going through 1st gear in a 6R80 so damn quickly that it's tough to get a good up-shift point established in the tune especially with a very powerful car. Also with todays technology, making a boat-load of power with a Coyote is being done alot, and rear gears dipping below the stock 3.15 ratio aren't the easiest thing to come by for an 8.8.
If I was to build my Motor some day and boost it up to have over 750 or more hp to the wheels I think I'd at least try doing something like this before ditching my nice overdriven 6R80 and going to a non OD C4, TH400, or powerglide, and I'd think it would be alot less finicky to launch and tune for the shift points than simply staying with the 3.15 rear gears, and running up to a 30" tall tire?? Also with 4.30 gears @80mph, you'd still be under 3K in 6th gear with a 28.2" tire, if you was worried about the highway driving capabilities of the lower rear gears.
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