how good are 317 heads for LS1
#2
Banned
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Id keep the 317's in reserve if you do decide for the forced induction, but for a NA application, there are a lot better options. The 317's bump your compression down, but they flow ok. I would invest in 243's anyway over even ported 317s for a NA motor. Should get half a point of compression and they flow well with good velocity and you can really port the exhaust side out well. Just my 2 cents.
#3
Id keep the 317's in reserve if you do decide for the forced induction, but for a NA application, there are a lot better options. The 317's bump your compression down, but they flow ok. I would invest in 243's anyway over even ported 317s for a NA motor. Should get half a point of compression and they flow well with good velocity and you can really port the exhaust side out well. Just my 2 cents.
#5
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If you are dead set on Forced Induction put the 317's on.
Personally I would put the 317's on after they were ported by one of the sponsors on the right, put in Brute speeds forced induction cam- stud the motor and get ready for boost in the future.
You could always clean up and port the 317's and hold on to them untill you go FI.
FI is expensive- look into it and understand how much it will cost before you put the 317's on.
Personally I would put the 317's on after they were ported by one of the sponsors on the right, put in Brute speeds forced induction cam- stud the motor and get ready for boost in the future.
You could always clean up and port the 317's and hold on to them untill you go FI.
FI is expensive- look into it and understand how much it will cost before you put the 317's on.
#7
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That's because the 317 and 243/799 head share the same ports. The only difference is the cc of the chamber. IIRC the 317 has a 70cc chamber and the 243 has a 64cc chamber. IMO.. if you are seriously thinking FI; install the 317's unported and crank up the boost to compensate for the cost of port work, you'll reach your hp limit without the cost. I would look at a conservative cam for the compression loss, that would help out if you are that worried about it. You should have around a 9:5cr without doing the math. Just a thought for you as I'm sure you've noticed, people practically give 317's away just to clean out their garage, and they flow better than the 241's.