i needa cam expert
can someone tell me the difference between these cams.
one of these will go in my 408, if i go with the hughes i don't have to change springs.
hughes: heh 4246 al - 555/569 lift 242/246 dur lsa is 108
lunati voodoo 405 - 533/552 242/252 lsa is 110/106
how will these cams act compared to each other?
i'm going for 10.5:1 compression and mildly ported eddy heads.
When you have cam specs this close, you'll really want to know the flow rate of the heads in and out.
History first. Split duration cams;
Split duration cams came around in order to help the engine breath better since the exhaust port doesn't get all the used air and fuel charge out. This leads to a contaminated charge next time around.
They were first designed to help stock heads.
Knowing the flow rate of the stock head, the industry played around with various exhaust durations. Crane Cams had about 10 - 12 degrees more exhaust. Excellent for stock heads.
With ported heads, the amount of duration on the exhaust can possibly be decrease. How much depends on the flow rate of the ports. To say, "Mildly ported heads" leaves alot to imagine.
Another thing, ramp speed of the cams profile will have an impact on power. A faster rate will produce more power.
What exact Comp cam you have is also a major issue to how the engine will act and make power.
On the Heuges cam, you only list 1 number, being 108. Is that a 108 centerline or where it is installed. The Comp Cam is listed with 2 numbers.
Lower the centerline number, the more top end pop the cam will have as well as a ruffer idle.