can someone please tell me the chamber size on my 86 305 TPI?
i've looked in tons of places but cant seem to find it. someone here has got to know what they are.

 

should be 58cc's...........

 

You're talking about the combustion chamber right? All thirdgen f-body 305 heads are 58cc, and all thirdgen f-body 350 heads are 64cc.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-

 

General,

YOU have an '86 TPI?!

Have you checked your PROM, lately?

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Later,
Vader
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"No matter how hard you try you can't stop us now"
Adobe Acrobat Reader 4.0

 

im pretty sure its the bad one, havent checked, but im dropping in a 350 with my TPI on it, so i was planing on getting a factory 350 one or a custom one. the reason i asked about the heads is i cant decide wether to use the 350 heads(76 cc, 1.94/1.50) or the 305 heads. i either got 9.0:1 CR, or 11.1:1 CR.
dont know which way to go. what do you think?
the castin number on the 350 heads ends in 624 if you wanted to know.
either way i gotta do a valve job and seals, so i dont know what to do.

 

Why would you use 76cc heads on a 350, unless you're going with a blower or turbo? Get 64cc heads or similar. And dont bother with 305 heads on a 350. They're too small to support it.

 

I'm buying a '69 Elcamino that's got a 350 with 305 heads. It does 11's. Depending on your cam profile, the higher comp. ratio will help.

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'82 Firebird, dead stock, 9 bolt disc rear, over 200,000 miles and still going strong, more to come...

 

Actually I've read the actual chamber volume is 55.3 cc. When Hot Rod put L98s on the 305 they had to shave them a little to maintain the compression ratio.

Jason

 

the 76cc heads came with the 350, they're free. the 305 heads are on it now, so they're free. i have no money, so FREE is GOOD. so im stuck with either the 305 heads, or the 76cc ones. unless someone wants to donate a set of 64cc ones to me.

 

Then I would highly recommend that you fillet/chamfer the chamber's edge (to block mating surface) to remove any potential hot spots that could cause detonation. Also polish the chamber and port the runners like there is no tomorrow.

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George P. Lara
1994 Z28 LT1 T56
1984 Z28 High Output
Member: SCCA, SCFB, SC3GFB
Chevy Info --> MadMike's