Quote:
Originally Posted by madmaxx
What do you guys think about this cam for a 427 stroker?
Intake Duration at 050 inch Lift: 236
Exhaust Duration at 050 inch Lift: 248
Duration at 050 inch Lift: 236 int./248 exh.
Advertised Intake Duration: 299
Advertised Exhaust Duration: 327
Advertised Duration: 299 int./327 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.574 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.595 in.
Valve Lift with Factory Rocker Arm Ratio: 0.574 int./0.595 exh.
Lobe Separation (degrees): 110
I had one for years but it required 450 lb open and 220 seat to keept the valves from floating, I used ford racing stock hydraulic lifters with no ill effects. Last time I spoke with owner he had 40K on the engine.
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I like to run a little more lift and with a modern cylinder head, unless you're drag racing, there's no need to split the duration by 12 degrees. Most of the newer heads, such as the AFR pieces, Trick Flow, etc., have exhaust flow that is way over 70% of the intake side. You can run a 3-4° split and cut the overlap way down.
The intake duration at 236-238 is about where I'd head for a 427. I have some lobes that I like that are not noisy, not overly lazy, and not overly aggressive. You lose a lot of cylinder pressure with advertised durations way over 300 like that.
For spring pressures, I can turn 6500 on a SBF with a hydraulic roller and 150/375 spring pressure. It takes a correctly designed lobe and eyeballing the weight of the components.