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Old 09-27-2011, 05:01 PM
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cucumber1949 cucumber1949 is offline
T-Bucket, Corvette, Mustang
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What is it the car will be doing most of the time? Are you planning on regularly racing it? Or will it be a street cruiser most of the time.

There are a lot of details when planning your setup, but from a high level view, consider the following. If your racing, then yes you need to closely match up all your components to get the most performance per run. You will want your torque curve up higher in the RPM band, matching it to shift points and torque converter stall, but choosing the highest ratio in the rear you can without running out of RPM at the end of the run. Lots of variables here.

If it is a street cruiser, then you have other objectives. The car is so light that even a mild street engine will make this car move, and move briskly. The race setup won't be very streetable. A 4.56 gear on the highway with a TH-350 is annoying and not very efficient. You'll want your torque curve lower in the RPM band, good vacuum and idle, and you'll probably want your torque converter to have a lower stall, and you'll want your cruise RPM to be reasonable so a numerically lower rear gear helps out here.

The setup in my T-Bucket is similar to yours and it is a mild street cruiser, good idle, high vacuum, stock cam, but can melt the tires if you want (not very much weight on the back end anyway so the tires are easy to break loose). Sometimes I think the 3.73 gear I run is still too high for long periods of highway cruising. You can still get a lot of power here - mine was timed once when I could keep it hooked up at 3.85 seconds for a 0-60 run - that will outperform 95% of anything else on the street and it still behaves well when you keep it on a leash.
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