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Re: Rear End Pain
There's not a huge difference between a 3.55 and 4.11 - only about 14 percent. To get a really significant reduction in highway revs you need to drop to a 3.36 or 3.08, but that's going to reduce off-the-line performance and could result in short clutch life if you live in a hilly area.
It's easy to compute top gear revs at 60 - axle ratio times 760 or 775 depending on whether you have 6.70-15 or 7.75-15 or equivalent revs per mile radials. From this number you can linearly proportion to any speed.
C2 mechanical lifter engines with CR 4-speeds were available with axles from 3.08 to 4.56. At the extremes they are like a five speed with no fifth or no first gear. The best compromise for the era was the 3.70, which was typically standard.
"Shifter buzz" is a designed in feature, and is most prevalent on models that have the linkage bolted directly to the transmission.
Reports from owners who have had their engines precision balanced during the rebuild process indicate that shifter buzz is eliminated or signficantly mitigated, and if the driveshaft is out it's a good idea to have it precision balanced by a properly equipped and experienced shop.
Modern balancing equipment produces better than OE balance and is worth the price in overall operating smoothness.
Duke
There's not a huge difference between a 3.55 and 4.11 - only about 14 percent. To get a really significant reduction in highway revs you need to drop to a 3.36 or 3.08, but that's going to reduce off-the-line performance and could result in short clutch life if you live in a hilly area.
It's easy to compute top gear revs at 60 - axle ratio times 760 or 775 depending on whether you have 6.70-15 or 7.75-15 or equivalent revs per mile radials. From this number you can linearly proportion to any speed.
C2 mechanical lifter engines with CR 4-speeds were available with axles from 3.08 to 4.56. At the extremes they are like a five speed with no fifth or no first gear. The best compromise for the era was the 3.70, which was typically standard.
"Shifter buzz" is a designed in feature, and is most prevalent on models that have the linkage bolted directly to the transmission.
Reports from owners who have had their engines precision balanced during the rebuild process indicate that shifter buzz is eliminated or signficantly mitigated, and if the driveshaft is out it's a good idea to have it precision balanced by a properly equipped and experienced shop.
Modern balancing equipment produces better than OE balance and is worth the price in overall operating smoothness.
Duke
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