combustion chamber on heads
10-22-2003, 02:54 PM
#1
combustion chamber on heads What does the combustion chamber size affect the most on heads for out ls1 enginges? I am looking into buying a new set of 205cc cnc ported AFR heads and they come with two different sized combustion chambers. I believe the chamber size only affects the compression ratio am I right? So I would want a larger chamber size for high psi FI or heavy doses of N02.
10-22-2003, 03:22 PM
#3
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Re: combustion chamber on heads do a search in internal engine and you should find a very in-depth thread on this topic, and why people feel these heads should outperform current heads. i can only offer a rudimentary explanation.
combustion chamber size is important when comparing flow rates for one. when you can flow 330cfm's thru a chamber at 205cc's, compared to heads that flow 300cfm's thru a chamber at 243cc's, you're increasing efficiency. you're also increasing velocity, which helps lower end torque.
like i said, try to find the AFR post in internal engine. i think it was originally posted by tbyrne.
btw, yes these heads are completely new castings, the first aftermarket castings for ls1's. they are re-inforced all over the place, and they have a .75" deck thickness....very nice for boost :-)
combustion chamber size is important when comparing flow rates for one. when you can flow 330cfm's thru a chamber at 205cc's, compared to heads that flow 300cfm's thru a chamber at 243cc's, you're increasing efficiency. you're also increasing velocity, which helps lower end torque.
like i said, try to find the AFR post in internal engine. i think it was originally posted by tbyrne.
btw, yes these heads are completely new castings, the first aftermarket castings for ls1's. they are re-inforced all over the place, and they have a .75" deck thickness....very nice for boost :-)
10-22-2003, 03:32 PM
#4
Re: combustion chamber on heads I've read the posts on AFR heads and there isn't any real information on the combustion chamber size and what it does. There is alot of info on intake runner size. Why would you want a larger or smaller combustion chamber is my question. What affect does changing the combustion chamber have on the engine? Does it affect the compression? Anything else? I know the 205cc refers to the intake runner size and I think the combustion chamber sizes are something like 65 and 75.
10-23-2003, 05:35 PM
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Re: combustion chamber on heads The AFR heads come with either 66cc or 76cc combustion chambers.The difference of 10cc is about a full point of compression on an ls1 346ci motor.
