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Old 01-08-2025, 03:57 PM
martureo martureo is online now
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Join Date: May 2010
Location: DC Metro/Maryland
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Quote:
Originally Posted by Frank Reiner View Post
The gear ratios of that box were intended for use with relatively small displacement gas engines, that have low torque at low RPM.
That's one reason I was looking into getting one from Europe. They were found on the 2.2L CDI engines in the C203. I figured that would be a decent analog.
Quote:
1st gear is very short - 4.46:1
2nd is rather tall - 2.61:1
6th is .84:1

You would use a 3.46:1 final, and in 6th would have an overall ratio of 2.9:1; not too bad, actually. However, starting in 1st would be an overall ratio of 15.43:1, which is very short for an OM603. If you started in 2nd the overall ratio would be 9.03:1, a bit tall for other than level ground.

A gearbox with an ~3.75:1 first, and an ~.81 top gear would work much better.
I would love to know where you go the gearing for the 716.6, the numbers I got were:
1_5.014
2_2.831
3_1.789
4_1.256
5_1
6_.828

I know there's supposed to be a different gear spread between the 716.60/64 (spread of 6.1), 716.62 (5.5) and 716.66 (5.3). I'm thinking I have the numbers for the 716.60 and you have the gearing for the 716.66.

I was planning on using the w123 differential with either the 3.07 or the 2.88. With the 2.88 and your first gear (4.46) it would give me a overall of 12.8. Do you think that would be decent?
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