Anyone ever used 11:1 compression pistons with HD CNC ported heads and woods 777 cams?

lookin to see what kind of numbers to expect as well as if anyone has had any problems with detonation or pinging

 

Using CP pistons with MVA heads(110 heads cnc ported) 11.5-1, wood 9f cams, 210ccp. You will be around the same cranking pressure. I will tell you don't even try to tune it yourself or load a break in tune. Have it broken in and tuned on dyno right away. If everything goes perfect you might hit 120hp but I wouldn't bet on it.

 

definitely going to get it on the dyno as soon as possible. Right now it has 777 cams and cp 10.25:1 pistons making 110hp/130tq with rinehart true duals. Switching to D&D fatcat and since i was going to put it on the dyno anyway, might as well work my heads for bigger valves and throw in a set of higher compression pistons since i have them already.

 

You won't gain much in hp with the exhaust switch, rinehart td's are 2" pipes. I'd go boarzilla not fat cat. But once you start trying to make more power there will always be a compromise somewhere. More compression means more fuel and more heat. Head work/bigger valves to make more hp will almost always result in lower air speed at lower rpms. 777's are decent cams but are tq biased as you know. Have a plan with the head work and change cams if the plan makes the cam change something that makes sense with the head work. Otherwise you are spending money on exhaust, headwork, pistons and tuning and won't see much in gains.

 

10.5 is basically where we'd sign off, with that intake closing number.
Scott

 

Would i be better off using an .030 head gasket or just leaving the compression alone?

 

W/O deck measurements, combustion chamber volume, etc, can't give a good answer to that question.
Scott

 

They are the CNC Ported heads from harley

 

Still not enough accurate info for me to say one way, or the other.
Scott

 

approximately 212 ccp with the 777 cam. too much for the street or daily rider... JMHO..... a 50* cam would work better but then you'll need more work to the heads to support the cam.... Don't see the need for a change with 130 lb of torque...