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Found A BBC local to me, but unsure of compression


BigBlockMonte

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Hey guys I found a pretty fresh BB local to me. The guy doesn't know every in and out on the motor but this is what I'm told.

 

1972 454 Block bored .20 over

Forged Manley Rods

427 GM Steel Crank

Forged Pistons (Name Or Part# Unknown at this time)

Heads 3919840 (67-69) 427 heads valves 2.19/1.88

 

tells me compression is 11:1

 

Camshaft is a Crane Cam Part # F 252

Lift 6.08 Intake/6.28 Exhaust

250/260 Duration @.50

Lash @26

LSA @ 114

 

1.8 Roller Rockers

 

Also comes with Fluid Dampner, Flexplate, intake, 750 holley carb, 2 sets of headers ( hooker super comps I believe)

 

Can I even run an 11:1 compression motor on the street on 93 sunoco gas.

 

How could I easily lower the compression?

 

What size converter would I have to run with this motor?

 

 

 

Help me out please.

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Well I found the cam card on crane's website. It doesn't look like this cam is street friendly at all. I'll let you decide.

 

http://www.cranecams.com/index.php?show=...lvl=2&prt=5

 

Looks like I may have to pass this one up. Too much to have to change to make it a little more streetable. Again, I'll let all of you decide. You guys know best.

 

Here's the guy ad on craigslist.

 

http://pittsburgh.craigslist.org/bar/1919553841.html

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well if it's got a 427 crank in it then I don't think it can be a 454.....a 454 stroke is 4" and a 427 stroke is 3.76"...both have a 4.25" bore. the compression would be on the edge for pump gas. You might be able to lower the compression with some thick head gaskets but not much. With that cam you would need at least a 3000 converter, maybe even a 3500.

 

the cam is pretty heathy for a street motor. The lift isn't too bad but the duration would probably be challenging the vacuum and very lopey....

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I think that the heads are the early style closed chamber heads. It would be nice to know what pistons are in it. Cam is a bit lumpy for a 3.31 gear. I think I would pass.

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Well I'm passing on it. Found out the guy selling the motor wasn't the builder or the original owner. Got a hold of the original owner of the motor, and he says it is a 427, has chevy rods(not forged) it has 11.1 trw pistons, but the heads have been shaved and the block decked, so compression is closer to 12:1. Its bored .30 or .60 over not .20. And its not fresh. It has between 100-150 runs on it. Didn't run 10.10's ran consistent 10.80's. I was like wow. Thank you very much you've been a great help in my decision making, & hung up.

 

So I'm passing. smile

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