Author Topic: Correct M20 Speedometer Gear?  (Read 97 times)

1967SS-Dave

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Correct M20 Speedometer Gear?
« on: April 29, 2025, 01:12:26 PM »
When I bought my 67 it was after a frame off restoration was done. When I got it the rear ratio gears were 4.98:1 !!!! So the first thing I did was put a reasonable drive-able gear set 3.07:1 back in the car and installed a new POSI unit while it was out.  But the speedometer has always been off and slow. At 65mph by the GPS it says I am doing 50mph. As these gears are $20-35 each and there are several of them it could be. I don't want to buy a lot of gears just to sit in a box and unusable. SO this question is. Does anyone know what gear they may have in the transmission to put the speedometer back to a true reading with the same setup I have or "Close"
3.08:1 Ratio26.5" tiresM20 Muncie 4-speed
Dave
1967 SS-396 Marina Blue (Clone)
05C-67-12437 NOR121785
717-Z/W/2L/3K/4P/5Y

Mike S

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67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

bcmiller

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Re: Correct M20 Speedometer Gear?
« Reply #2 on: Today at 04:01:32 PM »
Dave,

I will try to do some checking for you later today.
Bryon / 1968 Camaro SS 396 coupe - now old school 468 big block
1967 Camaro RS/SS 396 coupe L35/M40 - project
Looking for 68 Camaro with body # NOR 181016