At what point do GM heads not cut it?
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At what point do GM heads not cut it?
Im tryin to cut down on the build so that i can get it on the road now and then over winter get the parts that take a month to get. Like AFR heads. So im wondering what kinda power or PSI yall think i should limit myself to with GM cast heads. Ill be at about 9.0-1 CR with 72cc heads. I know its all in teh tune i got that part down pat but at what point would it become a issue.
Also i tried search 3 times and it appears to be borked. I woudl much rather have just searched out the answer as im sure this is asked and i just missed it.
If u have any input and maybe my parameters of teh answer dont work for ya then answer it the way u can make it make sense. Thanks Guys
John
Also i tried search 3 times and it appears to be borked. I woudl much rather have just searched out the answer as im sure this is asked and i just missed it.
If u have any input and maybe my parameters of teh answer dont work for ya then answer it the way u can make it make sense. Thanks Guys
John
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661rwhp on the stock bottom? Is there a forged setup in your garage ready to go?
Theres 750+hp setups running 317 cast heads. Some have gone to 900hp without lifting. What are your goals? Are you keeping the phamspeed kit? That way you can determine if a GM head will get you there, so you can save the $.
Theres 750+hp setups running 317 cast heads. Some have gone to 900hp without lifting. What are your goals? Are you keeping the phamspeed kit? That way you can determine if a GM head will get you there, so you can save the $.
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Have gone 157 mph at 3450 lbs (gotta be close to 1000 at the crank I think?) on stock 241 castings (ported)...20-22 lbs of boost. No problems thus far have around 30 passes on it.
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uhhh ok well that settles that lol. Every Engine builder i talked to said no way in hell over single digit psi lol. Obviously that is conservative but 170 mph sells me lol. Ill get other heads in teh winter.
Also i do have the forged engine now but i made 630ish for about 6 months with not a single problem. I attribute alot of that to my partner in crime Jerm, aka Zombie. He got me a great base tune for the car and i did some minor tweaking to make that power at 11.0 afr at 12 psi. I was happy but not enough.
Im definatly still gettin darts or afr's not decided on that yet. Anyone have any ideas on how big the bowl cold be ported on dart or afr heads to get a bigger CC size? Or is there a point where its takin away from teh mechanics of the combustion chamber mechanics? Thanks for the help guys!
John
Also i do have the forged engine now but i made 630ish for about 6 months with not a single problem. I attribute alot of that to my partner in crime Jerm, aka Zombie. He got me a great base tune for the car and i did some minor tweaking to make that power at 11.0 afr at 12 psi. I was happy but not enough.
Im definatly still gettin darts or afr's not decided on that yet. Anyone have any ideas on how big the bowl cold be ported on dart or afr heads to get a bigger CC size? Or is there a point where its takin away from teh mechanics of the combustion chamber mechanics? Thanks for the help guys!
John
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So you asked if GM heads would cut it...you get replies that say yes they will cut it way past the power you want...and then you say:
I don't get it? What was the point of making the thread if you had your mind made up already? lol
Im definatly still gettin darts or afr's not decided on that yet.
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I don't get it? What was the point of making the thread if you had your mind made up already? lol
170mph on 317 heads here.
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Originally Posted by 99SS-T
I attribute alot of that to my partner in crime Jerm, aka Zombie. He got me a great base tune for the car and i did some minor tweaking to make that power at 11.0 afr at 12 psi.
John
John
P.S. got two other local guys making around 600 rwhp on stock motors and they have been doing it for 8 months now.
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Originally Posted by JAvenger007
Is zombie running 317s also?
My setup is an uber budget build, i'm quite happy with it too.
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I'm hoping to hit 650rwhp & 800rwtq this weekend with my 317 heads. I'm at 9.3 CR & running ~ 14 psi. I think if you use good gaskets & bolts (studs) you'll be fine. I think your stock bottom end will go away long before the LQ9 heads develop a problem.