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347 stroker edelbrock performer RPM cam, intake, and heads(1.90" intake) and edelbrock 600 carb, about 10:1 compression. I was going to go with a 9" but read that the 8" is good for 400HP. I dont think I will be putting out that much HP. I was thinking of having someone build me an 8" center section with 3.55's and posi. What do you think? I will have a TKO behind the 347.
Thanks
 

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IMO as long as you are not running slicks and/or doing 5k launches, the 8 inch rear will be fine. With the TKO tranny you can actually step up to a 4.11 rear as well with out much worry and have even faster start ups, but as with most things, the Rear gear selected needs to match your total combo, what is your projected operating RPMs? If it is like 2500-6000 then as I understand it the 4.11 would be a better choice because it will put you into your power band faster, but if your rang eis 1000-5000 then the 3.55 might be the better choice because you will get into the band fast, and not out of it too quickly ;)
 

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Similar strokers make over 400hp at the flywheel at least in MM&FF. I would think with a manual transmission and a tight clutch you will have the ability to bust your 8" especially if you put on bigger rubber or God forbid; slicks.

Or you could drive it forever if you don't abuse it. To me it's more a matter of how you're going to drive it. IIWY I'd either stay with the 8" as is OR upgrade to a 9" posi. If you spend money on the 8" and then bust it...that's money down the drain.

Phil
 

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Depends on how you drive.
When my motor was slightly modified (270 degree cam, performer intake, 600 Holley, headers, 4:11 rear) it didn't take long to bust the 8".
Now I have a 31 spline 9" and a bunch more HP...no worries mon ::
 

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A well built 8" can withstand alot of punnishment.. a stock 30+yr old 8" may not last heavy use.. I'd say if you have the cash to build an 8 you can build a 9 and be safe.

AJ
 

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Marginal with no room to grow. 8" rears like to spit pinions, especially in the higher numerical ratios. As was mentioned, you can build one to take the abuse but you'll spend dollars commensurate with a 9" to do it.

If you're staying on street tires and have a fresh rear (all new parts), I'd be comfortable leaning on it but keep the shock loading to a minimum...
 

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with special emphasis on "shock loading"

a 347 with the unported edelbrock intake and heads (along with 10:1 comp) will put out just above 400 cshp as well as torque.

I would really think about fnding a 9 inch 31 spliner for this car....and a
hefty transmission like the TKO....

when building a powertrain like this, you have to match the drivetrain to it....as the chain is only as strong as its weakest link.
 
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