408 aluminum head choice for 500Hp
With a solid "street" roller with approx the same specs as the one Brian used there would very little if anything in it. Virtually all the dyno programs inputs don't differentiate between hydraulic roller and solid roller, why do you spose that is? I will admit if you have a VERY serious engine that makes power at high RPM a solid roller is a better choice.
It would be interesting to get Brians views on this 'leaving 100 HP on the table statement'
I hope he adds his opinions too.
As far as mine.... I said "upwards of". Not "100hp". As I've said, not every engine will leave that much, and I'm sure some could find more. You're also placing 100% of the gain on the camshaft. It's not just the camshaft but rather the setup and the amount of re-engineering for the solid roller that "finds" power and rpm. Stuff like additional static compression and higher cylinder pressures, fixing as best one can the poor lifter angles when the block is bushed, alleviating some of the pushrod angle issue, the cam lobe design, the lack of lifter compression absorbing lift early in the lift cycle, and a possibly lighter valve spring pressure requirement all add up to more power.
On the dyno sim remarks... I don't "suppose". I know that it's because most dyno SIMULATOR programs couldnt tell you the difference between 7° more exhaust duration at .100 lift and a ham sandwich. Simulators take a curved lobe shape and turn it into straight lines in order to make calculations based on valve position. They average cam shapes, flow values, and manifolding science in order to plot a pretty little line and convince people to buy product. Put the engine on a dyno to get closer to truth, or preferrably in a car and run it down the track to get solid reality.
Now on the camshafts - Solid roller lobes do not have "exactly the same" shape as a hydraulic roller. You are correct in that an identical lobe with a solid body lifter would make the same power. It would carry the power curve to a higher rpm too, and not need as much valve spring to do it. But if a builder spends four figures of your money on what I believe is properly prepping the block and buying all the required hardware for a solid roller, and then specs one that is similar to a hydraulic profile, or simply doesnt take advantage of what it lets him do, you really spent money with the wrong guy. The power will come from taking advantage of everything I mention. It comes from what a solid roller profile enables a builder to do as a result of running one as opposed to a drop in hydraulic roller.