1937 rear axle ratio

Queries about model and year identification, engine and vehicle numbers, etc.
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Olivierdejong
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1937 rear axle ratio

Post by Olivierdejong » Sat Jun 11, 2022 11:35 am

Hello.

I’ve been told that there is some sort of mark on the rear axle to identify the ratio.
Can anyo;e tell me what ki;d of figures/ marks I should be looking for? And where on the axle?
My 37 Victoria super 8 is running so high that I guess it’s very short...

Tx in advance.
Best regards.
Olivier
Olivier Dejong
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Packardclubbelgium@yahoo.com

Dave Czirr
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Re: 1937 rear axle ratio

Post by Dave Czirr » Sat Jun 11, 2022 12:23 pm

I'd suggest that a better way is to jack up one back wheel, rotate the assembly and actually measure the ratio directly rather than rely on marks which may or may not still represent the ratio.

Olivierdejong
Posts: 162
Joined: Wed Jun 17, 2015 12:40 pm
Location: Brussels - Belgium
Contact:

Re: 1937 rear axle ratio

Post by Olivierdejong » Sat Jun 11, 2022 12:53 pm

Ok i understand the jack up of one rear wheel, and turning it. But then...? It’ll make a turn and so what?
Olivier Dejong
+32 477 308 669
Packardclubbelgium@yahoo.com

Dave Czirr
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Re: 1937 rear axle ratio

Post by Dave Czirr » Sat Jun 11, 2022 2:10 pm

The rear axle ratio (4.36, 4.69 or 4.90 for the 1937 Super Eight) is the ratio of drive shaft rotations to driving wheel rotation. So with one back wheel elevated and the other stationary on the ground, just measure how many turns of the driveshaft are required to rotate the rear road wheel exactly one revolution. Then to compensate for the differential gearing either divide or multiply (I forget which) your result by 2 for the ratio.

Those ratios seem awfully high today but were a reflection of road capabilities of the era, noting that many of the nation's roads were still unpaved.

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