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**aotte1** · 12-02-2015, 01:36 AM

Interested in your thoughts on going to 3.31 gears if I read things right, with SM420 trans. I am in process of deciding which gear ratio to use, as will be rebuilding both front and rear axles soon. Planning to look at 3.08 to 3.73.
Need to look at first and second trans ratios to see what my minimum speed will be in each, e.g. 1500 to 2000 rpms in first and 1000 to 1200 in 2nd.

Changed gear in '86 with LY6 over drive 4 speed, from 3.08 to 3.73, because it was to fast in first at idle, minimum speed was 8 to 10 MPH with clutch out. Hard to drive in traffic.

Les

12-02-2015, 01:36 AM	#622
aotte1 Registered User Join Date: Oct 2013 Location: lousiville Ky Posts: 2,645	Re: 61K10 build Interested in your thoughts on going to 3.31 gears if I read things right, with SM420 trans. I am in process of deciding which gear ratio to use, as will be rebuilding both front and rear axles soon. Planning to look at 3.08 to 3.73. Need to look at first and second trans ratios to see what my minimum speed will be in each, e.g. 1500 to 2000 rpms in first and 1000 to 1200 in 2nd. Changed gear in '86 with LY6 over drive 4 speed, from 3.08 to 3.73, because it was to fast in first at idle, minimum speed was 8 to 10 MPH with clutch out. Hard to drive in traffic. Les