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Old 08-31-2006, 08:16 AM
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Pro's and Con's running 10.2:1 compression

I found a decent deal on some 64cc world sportsman 2 heads which would bump my flat top sbc 350 to about 10.2:1 compression i live in florida so i planned to put a/c on the car but some people are saying ill have overheating problems. The car wont be a daily driver but it will see alot of bumper to bumper idling in traffic and highway driving ,do they make a extra thick gasket that would get me in the 9.5 range if this is the case.THANKS

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Old 08-31-2006, 08:47 AM
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The important number to worry about is how much cylinder pressure you have. Also, good quench is important too. If you have poor quench, the engine can ping even with 9-1 static compression....stick in an RV type cam and you can have cylinder pressures over 200 psi and that'll generate plenty of problems. I build my engines to run around 10.5-1 with no more than .040 quench and they run fine.
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Old 08-31-2006, 08:49 AM
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The main problem is that it may not run on pump gas with 10.2:1 and iron heads. You could run a thinker head gasket, but then you will probably be hurting your quench which could also lead to preignition. Below is an article that exlpains quench and why it is important.

http://www.chevyhiperformance.com/te...earance_guide/

Adam
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Old 08-31-2006, 09:03 AM
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heads

Unless your engine has been zero decked with a flat top your static compression would be closer to 9.87... That is with a 10 cc gasket, 8cc's of piston volume and a true 64 cc head... Most heads are a few cc's greater then advertised....

I would never use a thicker gasket, The additional quench will make the engine more detonation prone....

What fuel do you plan on running in this engine??

How good is the cooling system on the car???

FI or carb??


Keith
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Old 08-31-2006, 09:11 AM
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i have 10.5, iron heads on my SBC 355, comp 292H, 244, 244 at 050. no issues overheating, i run A/C, no problems. but that big cam helps to bleed off cyl pressure like was mentioned before. and it runs on 91 and 93 quite well.
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Old 08-31-2006, 10:19 AM
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This is a carb engine with 2 12inch electric fans ,3 row radiator and new water pump.i just wanted to make sure i could run a/c with these heads and im willing to run 93 octane thanks for the help also in suggestion on a cam the motor is a sbc 350 40 over stock crank and rods ,headers ,holley 650 . 1.6 crane roller rockers ,40 series flowmasters planning on adding 3.73 gears and posi . This is in a 1984 2 dr olds cutlass with turbo 350 would like it to sound mean idling but still have alot of torque and power down low and possibly keep my stock torque convertor at least for a little while.
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Old 08-31-2006, 11:19 AM
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I'm not a fan of off the shelf cams and Scott Brown is at the top of the list for custom cams and he'll set you up and prices are good. http://racemufflers.com/ and his email is SBROWN@RACEMUFFLERS.COM
Don't let the name of the website fool ya.....
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Old 08-31-2006, 11:24 AM
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is that the "racer brown" i hear so much about for mopar guys??
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Old 08-31-2006, 12:05 PM
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Quote:
Originally Posted by firestone
The main problem is that it may not run on pump gas with 10.2:1 and iron heads. You could run a thinker head gasket, but then you will probably be hurting your quench which could also lead to preignition. Below is an article that exlpains quench and why it is important.

http://www.chevyhiperformance.com/te...earance_guide/

Adam
An interesting article but it doesn't actually delineate the difference between 'squish' and 'quench', which aren't one and the same.
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Old 08-31-2006, 12:46 PM
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Quote:
Originally Posted by hotrodf1
is that the "racer brown" i hear so much about for mopar guys??
No sir....
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Old 08-31-2006, 12:52 PM
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Quote:
Originally Posted by onovakind67
An interesting article but it doesn't actually delineate the difference between 'squish' and 'quench', which aren't one and the same.
How about this one? I didn't read it but it's supposed to explain both.
http://forums.corvetteforum.com/show...19&forum_id=48

Might look at this one too from KB pistons

http://www.moparstyle.net/forums/sho...ghlight=quench
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