Changing from 4:11 rear end to 3:55
06-20-2018, 02:17 PM
#41
Race Director
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Location: Fresno California
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Again, if you leave it all alone and just change the gear ratio out back, 3.70 would be fine with what you have. Lower numerically than that, you will be slipping that clutch to get it going. I would MUCH rather drive a car with a 3.70 than a 4.11 if I saw ANY highway use at all. (I pulled the 3.36 out of a GTO I have and replaced it with a 2.56.....and just love 21mpg at 80 mph, and cruising 90mph at 3,000 rpm. But the car has an automatic, so it's do-able). Point is, as we get older, and as we drive 'modern' cars today, putting up with a high-revving, gas- chugging turtle on the highway is no fun.
06-20-2018, 09:27 PM
#42
Team Owner
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Location: Washington Michigan
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Here's the "terminology story" between 4-speed RPO numbers and close-vs.-wide ratio gearsets: 
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Oaker57 (06-24-2018)
06-20-2018, 10:31 PM
#43
Burning Brakes
Three years ago I pulled the 3.36 out of my '62 and put in 3.08 gears for a trip to Indianapolis. Since I live in the country, any "cruise" I take results in highway speeds. I've just left it in, at least for the time-being. Just returned from a three day 1,460 mile trip-at 2800 rpm I'm cruising at 71 mph, and at 3000 rpm I'm right at 80 mph.
When I finish my current build, I have a fresh 3.36 or a 3.70 to throw in to the Corvette to wake it back up. Sure is a dog off the line!
Mike
When I finish my current build, I have a fresh 3.36 or a 3.70 to throw in to the Corvette to wake it back up. Sure is a dog off the line!
Mike
Last edited by mcb55-210; 06-21-2018 at 09:06 AM.
04-24-2019, 02:19 PM
#44
Melting Slicks
Member Since: Dec 2017
Location: Michigan
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2023 Restomod of the Year finalist
Can I use the same carrier and just change the gears out or will I need to get a new carrier as well. I thought I remembered back in the day, that carriers might be good from say 3:08 ratio up to 3:55 and then a different carrier was needed for higher gear numbers like 4:11 and 4:56. I would appreciate and feedback. This is for a stock 1962.
Butch
Butch
Probably having the 3:08 ratio will give you the best gas mileage.