in that cam swap article Andy did, the comp hydraulic went to 7000rpm.
http://www.moparts.org/Tech/Archive/bb/Lobe.html

seems like you could get quite a bit more rpm than 5600 with stiffer springs and stiff pushrods, even if you are running a more aggressive rocker ratio.

I've sold quite a few cams with the same lobes as what Andy ran in that test and I can tell you that his results on how high those profiles will go isn't typical.
They are usually "done" by around 6k, and lower as the ratios are increased.

If you go back and check out Dulcichs article on the 446 from October 2005 you'll see how the usual scenario plays out.

The Shubeck/Smith Machine is the best hydraulic lifter for radical lobes/rpm. They have a ceramic puck and can be used on many cams without break in. They are around 1,000 bucks a set but buy only once. I run 200 seat and 425+ over the nose at 7000+. Be vigilant on checking springs as if they get weak you can bounce the lifter and the ceramic has been known to shatter making a real mess. I have been using these for a long time without issue but am fanatical about checking things over.

Do you have a link to Dulcichs article?

You'll have to try a search and see if you can find it.
I have the actual magazine.

Mopar Muscle oct 2005

Try this:

http://www.hotrod.com/articles/mopp-0510-440-engine-dyno-test/

WOW! Both very good articles.

Also a great post here with a lot of good info!

The question for me is what HYDRAULIC lifter was being used in the two different tests?

There is some interesting info in the 446 build article dyno numbers of the later tests that they don't talk about, but the results bear it out.

bumping this, i'm curious if the y07 got any more rpm out of his combo...

I am still interested too! Our weather has not been good so the car still sets.
Thanks for the bump and I will check back in once I can get the new spring pressures tested.