3.91 is horrible

gearing drops maybe a 10th in the 1/4 from 3.15 to 3.91

dont ruin the car, keep the 3.15 and make it real light, you will enjoy 75 in 2nd

good luck with your project and do the headers before you drop the motor in! you will thank me

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Turbo lag is actually a headstart to make it fair