RPM ?s

72 Demon said
4. I have a Comp Cams 260H and an AussiSpeed 4bbl manifold I intend to install. Should I upgrade the valve springs, too?

Yes, you should always upgrade your valve springs to match an aftermarket camshaft.

72 Demon said
5. Have read that there are problems with oiling the camshaft at high RPM. True/False/Comments?

I'm aware of COMP cams having oiling problems/flaws, but not slant six cams in general. Most experienced slanters seem to have gotten away from Comp cams. There is an Erson group buy you can find out about over on slantsix.org that I'd recommend as an alternative. I'm not running one of the group buy cams (spec'd by Doug Dutra himself), but I'm running one of the last "standard" Erson 270 cams, and I'm very pleased. The only nice thing about Comp Cams with regard to slants is that their website is bigger/better. The Erson takes more effort, but it's worth it.

72 Demon said
6. If you have grenaded a 225, how did it happen? (If this get's too big, maybe I'll enlist a site admin & start a separate thread.)

Mine spun a main bearing. Does that count as "grenaded"? Gave me the opportunity to build my long rod engine, which I love.