Rocker arms for 408 build

Idaho said

I look at what's out there in the way of upgraded roller rockers and read stories of poor valve tip contact. Some great some not. I contacted the member here who makes correction kits, but these do not apply to Magnum heads. He had no suggestion for a rocker arm.

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This is a little misleading. I didn't have a suggestion for a rocker that would be the correct length for the RHS/INDY head, when the geometry is correct. A centered pattern can usually be achieved by running a pushrod that is way too short, but that isn't good geometry.

Because the fulcrum to valve centerline is so short on the RHS/INDY heads, most rockers in most applications will be too long. My suggestion, for it to be right, was that the studs would need to be relocated so the roller tip would stay reasonably centered on the valve tip, when the correct fulcrum height for correct geometry was established, via the correct length pushrod. I just don't know of any rockers that will meet that requirement without remachining the heads. If there was a rocker that short currently available, you wouldn't be able to fit anything bigger than a beehive spring in the head without hitting the rocker. The only other option that "might" work, is if Crower will make a set of offset trunnion rockers for you. Be prepared to pay dearly for them, though.

Correcting geometry is an involved process, and I try to make it as painless as possible with my LA kits, but on a Magnum, more work is involved, and it completely wipes out any savings by being able to use inexpensive stud mount parts.