# '70 LeMans posi rear question



## bobj_70 (Oct 22, 2009)

I have a '70 Chevelle with a 2.56 10 bolt rear. But i'm dropping in a big block and would like a posi with better gears. The guy i originally bought the car from years ago, says he has a 10 bolt Posi from a '70 LeMans laying around. Is the BOP 10 bolt posi a good unit?? and what gears did they come with? 

Thanks!


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## geeteeohguy (Feb 2, 2008)

The BOP 10 bolt is as good a unit as the Chevy, probably better quality. BOP rear ends used better fitted gearsets (quieter). Chevy got the cast-off gears. Ratios ran from 2.56 thru 4.33, with three different carriers. 2.56-2.73 take a 2 series, 2.93-3.23 takes a 3-series, and 3.36-4.33 takes a 4-series. Best bet with a lot of HP would be a 12 bolt unit (stronger), but the 8.2 BOP 10 bolt should be fine. See the Gear Ratio thread at the top section. Lots of info there.


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## Too Many Projects (Nov 15, 2008)

bobj_70 said:


> I have a '70 Chevelle with a 2.56 10 bolt rear. But i'm dropping in a big block and would like a posi with better gears. The guy i originally bought the car from years ago, says he has a 10 bolt Posi from a '70 LeMans laying around. Is the BOP 10 bolt posi a good unit?? and what gears did they come with?
> 
> Thanks!


Define "big block"...350hp 396 - 550hp 454. There is a reason all big block Chevelles came with a 12 bolt axle...


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