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Compression ratio help please.

SF87K5

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I am going to be putting new heads and roller cam in my 355 TBI soon. I want to run 9.1-9.5 compression in my engine. The heads I am getting are the World Products S/R Torquer heads and they only come in 76cc Combustion Chamber Volume. How do I go about figuring what size gasket I need to get the compression ratio I want.
Any help or links the this info will be very helpful.
 
Danny.....check your e-mail. I just sent you a Microsoft Excel file that you can use to calculate your comp. ratio. You will need to know alot about your motor to make an accurate calculation. /forums/images/graemlins/waytogo.gif

Oh and by the way...the S/R Torquers come in 58, 67, 72 & 76cc versions. /forums/images/graemlins/waytogo.gif
 
Here ya go. clicky
Type in part# H618CP30
9.38:1 compression with 76cc heads.
Values are calculated with a virgin block 9.250" deck, .025" piston deck height and a .030" compressed head gasget.
That would give a quench of .055".
That is all ballpark figures, you would have to measure it all out to get the final ratio.
Another click
A good read on quench. click
I have a set of Speed-pro's that I linked.
Now that I have to use another block and it will be .030 over I am going with the flattop 2 valve releif version.
8.68 with 76cc chambers, mine are prolly closer to 74 and I am going with a .050" quench. That should put me at 9's door. Which is what the cam I am going to use recomends.
I have never tried to soup up a TBI plant but I would think that 9.0:1 would be plenty, if the sensor detects detonation it will retard the timing and it will run like crap, especialy with todays flavor of fuel.
No need to build a plant that you can't take full advantage of.
Besides just ditching the stock dish pistons for flattops will be a good upgrade.
Read the clicky on quench and it goes into better detail on that.
 
Ben thanks for the e-mail, those are the only center bolt heads that world makes for 87 and up 350 sbc. I already called summit and jegs and the 76cc heads are it.

Powermad Thanks for the info you posted it helped alot./forums/images/graemlins/thumb.gif I need to check with the guy I got my 355 from and find out what kind of pistons he had put it.
 

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