Speedometer gear

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Apr 17, 2020 | 03:28 PM

7t9l82

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Le Mans Master

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From: melbourne florida

2023 C3 of the Year Finalist - Modified

Speedometer gear

My Speedometer reads 4 M.P.H slow at every speed. I have 3-55 gears and a 275-60-15 drag radial on the rear, I'm thinking about a speedometer gear for a 336 rear would get me closer to the actual speed. Any thoughts?

Apr 17, 2020 | 03:33 PM

0Willcox Corvette

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From: Jeffersonville Indiana 812-288-7103

St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15

typically, 1 tooth = 5 mph..... so I'd adjust accordingly.

Willcox

Apr 17, 2020 | 04:00 PM

7t9l82

Thread Starter

Le Mans Master

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From: melbourne florida

2023 C3 of the Year Finalist - Modified

Quote:

Originally Posted by Willcox Corvette

typically, 1 tooth = 5 mph..... so I'd adjust accordingly.

Willcox

Do you have a recommendation,?
Or a gear that would get me there 1 mph. Faster indicated is better than 4 slower.

Last edited by 7t9l82; Apr 17, 2020 at 04:05 PM.

Apr 17, 2020 | 04:36 PM

HeadsU.P.

Le Mans Master

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From: Cool Northern Michigan

Try Speedometer World. They have the color codes for the "driven" gear you need. Might want to put a new seal ( O-ring) on the gear holder too.

Apr 17, 2020 | 04:50 PM

7t9l82

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Le Mans Master

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From: melbourne florida

2023 C3 of the Year Finalist - Modified

Thanks.

Apr 17, 2020 | 05:57 PM

pspicci

Burning Brakes

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From: Western NY

what trans do you have? i know on my TH400 1 tooth on the driven gear equals about 1.5 mph. i have accumalted several gears over the years due to gear changes and tire changes.

Apr 17, 2020 | 07:53 PM

Big2Bird

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The gear set calibrates the odometer. When correct, the head is calibrated to the correct speed.
This is optimal of course, as speedo shops are becoming gone with the wind like radiator shops.

Apr 17, 2020 | 09:01 PM

7t9l82

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Le Mans Master

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From: melbourne florida

2023 C3 of the Year Finalist - Modified

Mines a turbo 350 I called speedometer world and he said 1 less tooth but I have to count the teeth on the factory gear. I can't believe it isn't listed somewhere.I'm sure every corvette with 355 gears used the same speedo gear in 79.

Last edited by 7t9l82; Apr 17, 2020 at 09:02 PM.