Thread: Gear ratio
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Old 09-06-2013, 10:07 PM
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GregWeld GregWeld is offline
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Quote:
Originally Posted by IndyNova View Post
I've got a bone stock 4l80e trans, with a 275/45/18 rear tire. I haven't ordered a cam yet, but I've been given a few ideas on what I should order.


Your tire is 27.74 inch DIAMETER


Your 4L80 is a .75 overdrive (final drive ratio)


If you have a small block -- I'd try to keep the 70 mph cruise at around 2000 to 2200 rpms.... same with a big block


3:70 = 2350rpms

3:89 = 2450rpms

4:11 = 2600rpms


These give you a rough idea of what you're dealing with

Last edited by GregWeld; 09-06-2013 at 10:17 PM.
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