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Old 08-21-2007, 01:16 PM
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How to size engine, trans, rear end

I have a 2400lb 2 seater with a SBC 350 mild cam, Edelbrock manifold, Saginaw 4 speed (don't know the ratios) and a 3.08:1 10 bolt posi. don't need 1st gear at all, is that typical? What would others suggest for a fast streetable drive train? how much more engine could I get to the pavement?probably limited to 26" dia tire

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Old 08-21-2007, 02:00 PM
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mild 350 is about 340ft/lbs of torque
340ft/lbs x 3.08 gears =1047ft/lbs of torque actually applied to the tires
2400lbs/1047ft/lbs=only 2lbs of weight per 1 ft/lb of force

normal 3200lb car/1047ft/lbs at the tires=3lbs of weight per ft/lb of force

that's why you don't need first gear....about 50% less weight than typical for that motor torque output at the tires

3.50 gears=1190ft/lbs to the tires (makes a big difference for neck jerk), leave the motor alone
3.73 gears=1268ft/lbs ="if" your suspension is set up for traction....cause in the will want to break loose with only 800lbs(?) on the rear tires to keep it planted to the ground

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Old 08-22-2007, 08:16 PM
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How to size

I'd have to agree with Red, I have a roughly 3400 pound car with maybe 400 hp and a 3:55 gear. It's a handful on any damp or wet road and will the spin the wheels from a rolling start with no problem. Then again, I used to race motorcycles, so, is there really such a thing as too much horsepower?......LOL.
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