1980 302 performance
Fleet Mechanic
Joined: Jul 2011
Posts: 1,916
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Go with the 3.55's then.
My 300 is talkin' at about 2950 rpm at 65 mph with 31's and 4.10s. That's without overdrive, just like your C6.
Although...
If it's a farm truck, it won't matter. Theoretically, if it's never going to go on the road, you could put 4.88's in it.
If there is a random chance you put it on the road, you'll want the 3.55s.
My 300 is talkin' at about 2950 rpm at 65 mph with 31's and 4.10s. That's without overdrive, just like your C6.
Although...
If it's a farm truck, it won't matter. Theoretically, if it's never going to go on the road, you could put 4.88's in it.
If there is a random chance you put it on the road, you'll want the 3.55s.
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
Nope, you missed nothing. Right on the money.
Fleet Mechanic
Joined: Jul 2011
Posts: 1,916
Likes: 4
How does the gearing indicate which rear end you've got? Wouldn't that be the axle code?
My 83 has an 8.8'' rear and came factory with 3.08 rear gears.
(I wish it was a 9'', but an 8.8 is fine with me).
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Brett Foote
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Some ratios are specific to the 8.8 vs. the 9.
3.55 = 8.8; 3.50 = 9 for example.
3.08/3.00 would be another, and maybe a few more. Of course, it's not a 100% method to determine the axle type.
A 1980 should be a 9'er out back.
3.55 = 8.8; 3.50 = 9 for example.
3.08/3.00 would be another, and maybe a few more. Of course, it's not a 100% method to determine the axle type.
A 1980 should be a 9'er out back.
Posting Guru
Joined: Jun 2009
Posts: 1,509
Likes: 1
From: Wagener, SC
Yea, what he said.
Posting Guru
Joined: Jun 2009
Posts: 1,509
Likes: 1
From: Wagener, SC