clutchdust
Millionaire Playboy
OK, here's my take on the issue. A mild flat tappet 383 will end up making about the same power as a mild 350 roller. Figure other things being pretty much the same, a roller is worth about 25-30hp over flat tappet and the extra 33ci displacement is worth about 25-30hp.
I like the roller for the obvious advantage of reduced friction but that's only half (less, actually) the advantage. The reason rollers are so much better than a flat tappet is how quickly you can open the valve and how much longer you can hold it at peak lift. Of course, the only downside (aside from upfront cost) is you need a little stiffer spring to handle the additional mass of the roller valvetrain. So if you compare a flat tappet cam and a roller cam with the same duration, the roller allows you greater lift within the same duration and you can pop that valve open so much faster. That's a major advantage to filling the cylinder.
Of course, the advantage would be both roller and increased displacement. Now, I'm not a huge fan of the stroker motor personally because it reduces the piston's dwell at TDC, and that reduces combustion pressure at the time of the event. But that's a torque vs horsepower argument. Blah, blah, blah.
But I'm just an expert on the internet.
I like the roller for the obvious advantage of reduced friction but that's only half (less, actually) the advantage. The reason rollers are so much better than a flat tappet is how quickly you can open the valve and how much longer you can hold it at peak lift. Of course, the only downside (aside from upfront cost) is you need a little stiffer spring to handle the additional mass of the roller valvetrain. So if you compare a flat tappet cam and a roller cam with the same duration, the roller allows you greater lift within the same duration and you can pop that valve open so much faster. That's a major advantage to filling the cylinder.
Of course, the advantage would be both roller and increased displacement. Now, I'm not a huge fan of the stroker motor personally because it reduces the piston's dwell at TDC, and that reduces combustion pressure at the time of the event. But that's a torque vs horsepower argument. Blah, blah, blah.
But I'm just an expert on the internet.