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Do you shift into 4 before the end of a 1/4 mile run? I'm running stock 3.25, I'm assuming a 5500 shift. I could go beyond 5500 but I'm trying not to, I really don't know if the motor could handle it. It's a 351W, pretty much stock, (hopefully not for long!) Thanks
 

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It's going to depend on many, many variables. Basically, you're just going to have to go out and see. I would say the majority of people don't make it to 4th gear, but a lot depends on your rear gears and how high you rev it.

When I'm racing the '66 with the AOD, I never shift out of 3rd, but I think it has a wider ratio than the standard 4 speed. I'm running 3.50 gears and shift at about 6500.
 

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You could calculate what your trap speed would be at 3rd and 5500rpm.
 

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I would try varying shift points in 500 RPM increments to see where it runs the best. Since your engine is pretty stock, it may not be making too much power passed 4-4.5K RPMs. Shifting at 5,500 RPMs may actually slow it down. Try starting at 4,000 RPMs. Shifting into 4th will be a function of shift points and where you are on the track. Don't lift untill you're through the lights.
 
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