Thread: Heads Port and Polish, Cam, etc

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The 08-301-8 likes 9.5:1 to 10.75:1 static compression ratio. Currently, according to you, the motor is at 10.50, so it is just on the edge of almost having too much SCR for the cam that's in it now. You want to move to a 08-443-8 which wants 10.5:1 to 12.0:1, so it will be on the other leading edge of almost needing more SCR. You're closing the intake valve at "X" degrees after bottom dead center now and when you go with more cam, you will be closing the intake valve at "X+" degrees. You will be extending the intake valve closing point, which means that compression in the cylinder cannot begin until the piston is further up the bore than it is now at valve closing. There may be enough additional fuel and air pushed into the cylinder by atmospheric pressure with the new timing and valve lift to make up for the deficit of piston position in the cylinder with the later intake valve closing position........or there may not. I see you between a rock and a hard place. You need more SCR, but the available fuel quality will not allow it. And you darned sure don't want to enter the threshold of detonation. If there is E85 within 20 or 30 miles of you, I'd sure be looking at changing the whole mess over to alcohol, along with a new set of pistons delivering maybe 12.50 or 13.00 to 1 SCR and twisting a 08-444-8 cam. You may have heard the hot rodders axiom from back in the '50's......"If some is good, more is better and too much is just right."

Now, as far as the heads, I stand by my statement to change over to Airflow Research heads, 220 cc intake runners.
https://www.airflowresearch.com/220c...cylinder-head/

Scroll down and look at the flow of the Race Ready head at 0.550"......you could be over 0.550" lift by using 1.6 intake rockers and leaving the 1.5's on the exhaust......304 intake and 225 exhaust......ZOWIE. I tried to find the flow on those Fosdick RHS heads, but it eluded me. OK, that's all I've got.
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