The right heads?
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The right heads?
I am in the planing stage of some minor hop up work on what is now a mostly stock 77 L-48. The engine has a Performer RPM manifold and Holley 670 street avenger carb. But is other wise stock,
I am looking at Twisted wedge 64cc street/strip heads, A crane, 327/350 HP cam, with 1.6-1 rockers. should give me a lift of approx .480 a set of summit long tube headers into a duel chambered exhaust.
(the exhaust is already on the car).
I am thinking the carb my be a bit small. What do you all think?
And also would like to know, what would my compression ratio be with the stock dished pistons with the 64cc heads?
Also of note, what if I put in flat top pistons?
The car is a street driven toy that will never see a drag strip.
I have had the car for many years. And now that I am getting divorced I would like to hop her up a bit.
My budget is not endless, so I want to get it right the first time.
Just looking for a bit more power, Must run on pump gas and not get to snotty to drive in heavy traffic.
I am looking at Twisted wedge 64cc street/strip heads, A crane, 327/350 HP cam, with 1.6-1 rockers. should give me a lift of approx .480 a set of summit long tube headers into a duel chambered exhaust.
(the exhaust is already on the car).
I am thinking the carb my be a bit small. What do you all think?
And also would like to know, what would my compression ratio be with the stock dished pistons with the 64cc heads?
Also of note, what if I put in flat top pistons?
The car is a street driven toy that will never see a drag strip.
I have had the car for many years. And now that I am getting divorced I would like to hop her up a bit.
My budget is not endless, so I want to get it right the first time.
Just looking for a bit more power, Must run on pump gas and not get to snotty to drive in heavy traffic.
Thread Starter
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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how could other components change the compression ratio? Swept displacement verses combustion chamber volume = ratio
Team Owner
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From: Columbia Missouri
Melting Slicks
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From: dayton oh
Thread Starter
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
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Granted. lets just say I use standard over the counter Fel-pro head gaskets. I think I read somewhere that the the stock heads were at about 76cc's. right now I don't wish to take the engine apart until I do get new heads. So cc,ing the stock heads just isn't practical right now. anyone have any better info?
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Thread Starter
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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I find that very interesting. Never heard this before. What type of wear are we talking about? It has takin me almost 20 years to put on about 40K miles. Is this a real fast guide wear problem?
Thread Starter
Race Director
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From: Sunshine Coast, Queensland, Australia
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What about GM fastburns? More info please. Price? Power?
Thread Starter
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another short answer. what are AFR heads? Power? Price? Who sells them?
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From: Living in the Hartland
Thread Starter
Race Director
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I am pretty sure on the cam I wish to use. I work on Harley's for a living, Run a dyno in a performance Shop. Don't like Edelbrock heads for Harley's. Simply don't live up to there promises. Still looking for a clear answer on compression. Also, if I Google everything, What do I need this forum for?
Race Director
Joined: Mar 2001
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From: Living in the Hartland
Thread Starter
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
I did do a fair bit of research before I posted in the first place. Could not seem to find a reliable source for the compression ratio's. Thought I would ask, surely someone on this forum would know small block chevy compression with different heads.
I can Google all night if I want to. Much nicer talking with real people.
I can Google all night if I want to. Much nicer talking with real people.
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
I did do a fair bit of research before I posted in the first place. Could not seem to find a reliable source for the compression ratio's. Thought I would ask, surely someone on this forum would know small block chevy compression with different heads.
I can Google all night if I want to. Much nicer talking with real people.
I can Google all night if I want to. Much nicer talking with real people.
I think your compression question using stock dished pistons was answered for you...unless that's not the answer you wanted.
I also added that using flat top pistons and 64cc heads would get you roughly a 9.75:1 CR.
