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I'm getting ready to freshen up the SBC 383 in our wingless sprint and want to change to aluminum heads. I have not torn the motor down yet so I don't know what pistons it has in it since we just bought it late last year. My questions are how do you know what head to buy? We are running alcohol and Hilborn injection if that makes a difference. Not sure of the cam either, all I know is it's a solid flat tappet but want to go roller. I want to go with T&D or Jesel shaft rockers for the heads. From what I've been reading I should be looking at a 215cc head with larger intake valves. I would also think a small combustion chamber to keep the compression up for the alcohol. I was comparing the sizes and thinking of buying the Brodix ASCS 360 legal head but I don't need a restricted head in an open motor class. Can someone give me some advice on heads so I know what I should be looking at and is changing to an aluminum head worth the extra $$ opposed to cast?

Thanks
 

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Make sure your CR is up there for alcohol.The air flow needs to be enough for the horse power you want to produce.The formula is different for alcohol because the fuel produces less heat.
rocker shafts are a greAT idea for the higher rpm.If you have no rules about heads then consider the 15-18 degree heads. The theory is the same as gasoline,just the fuel produces a different amount of heat/power.
 

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Before you tear it down,you need to leak it down to see where that engine is at.

Really can't give you recommendations without you giving more details of the parts you have.As a example,I wouldn't tell you to go to a bigger head with the wrong pistons or stock rods and rod bolts spinning it up higher.

All of our Alky engines are 13.5 to 14 compression.Ignition hot spark matters too.Bigger jets and air feed holes on carbs are apart of the puzzle too.

So leak it down,I.D.the parts and post what you have.
 

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http://www.warsprints.com
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Discussion Starter · #7 ·
Before you tear it down,you need to leak it down to see where that engine is at.

Really can't give you recommendations without you giving more details of the parts you have.As a example,I wouldn't tell you to go to a bigger head with the wrong pistons or stock rods and rod bolts spinning it up higher.

All of our Alky engines are 13.5 to 14 compression.Ignition hot spark matters too.Bigger jets and air feed holes on carbs are apart of the puzzle too.

So leak it down,I.D.the parts and post what you have.
Thanks 1Gary. I will post what I find out. I watched a show (Horsepower TV) I believe where they bought a 383 crate motor from Patriot built for alcohol. They tore it down to show the parts and then reassembled it for the dyno. This motor had FT pistons with valve reliefs, an Eagle rotating assembly, Roller cam, Patriot heads using a .015 compressed head gasket and an alcohol carb. It showed this motor making in excess of 600HP and 550+lbs of torque. Does this sound right or is it just TV?
 
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