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Old 10-29-2024, 12:29 PM
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VCho455 VCho455 is offline
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Join Date: Aug 2003
Location: PDX OR
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Here's a great gear ratio calculator to help you. It gives visual graphs of shift points and also allows you to compare transmission ratios.

One thing many folks forget about when making these choices is your overall ratio in first gear at idle. My LT1 T56 Blazer is a good example. With a cam and other bolt on parts it makes about 100 hp over stock. But with the upgraded clutch it's got a fairly stiff pedal (compared to new vehicles).

The problem was with 3.42 gears, 25 inch high tires and the atrocious 2.66 first gear that F-body T56's have stop and go traffic was tough as the car wouldn't go any slower than 5 mph without feathering the clutch. By changing the rear end ratio to 3.73's means the car to go 3 mph without constantly feathering the clutch making a big improvement in driveablity. The 3.73's also made 0.50 6th gear a usable option at 60 mph where before it was too much.

If your not racing the car and need to base your ratios on that then driveablity should be your goal. GM makes the ratio choices based on emissions and MPG as their foremost considerations with driveablity as the next consideration hence the 2.66 ratio in the F-body compared to the 2.97 ratio in the later C5's. (Keeping the CAFE average up helps them keep the cost of new Vettes down.)

Just my opinion which along with a couple sawbucks will get you a steaming hot cup of Joe just about anywhere.

https://www.blocklayer.com/rpm-gear

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