Would there be a benefit to using the stage 1 exhaust valve and the standard size intake valve on a set of heads for a standard bore 430? It seems like there would be less shrouding on the intake valve this way, and the bigger exhaust valve would help bring the intake/exhaust flow ratio into a better range. Just a theory- could be pure nonsense. Has anyone tried anything like this?
Do not know if it would help anything. All I can add is I use split ratio rocker arms 1.50 intake, 1:65 exhaust and does not seem to hurt anything. I suspect that it would depend on the cam grind. It should really work with nitrous.
Funny you should mention this, because, except for having a .030" over 400 instead of a 430, that's what my setup is, although not by choice. The friend that I bought my '67 GS400 from had the machine shop install the larger Stage 1 exhaust valves only, because the small bore of the 400 incher could not take advantage of the larger intake valves because of the shrouding problems. He was running a fairly radical Crane solid lifter cam at the time. But there was never any before-and-after dyno testing done to see if it really made any difference over the regular size valves. The car was only used for street racing, and he could rev it up to 6000 rpm with ease. All I can say is that it ran extremely well with 11.5:1 compression, M/T headers and Holley 1150 cfm Dominator on an Offy manifold. Now I've pretty much restored it back to stock condition, and it still runs fine, even with the larger Stage 1 exhaust valves. Larry
I figured someone probably tried it at some point. Too bad there wasn't any before and after info. On another note, I wonder what would happen if you run a fairly big cam and only put Rhodes lifters on the intake side. Seems like it could give you big torque down low and good horsepower too. Strange ideas. Thanks for the replies.
