I have enjoyed running my Ed head 496 for about 10 years and this year it got some meaningful road track time... and hammered a lot harder. At the end of the straights it is seeing 6250 RPM or more. I have the rev limit set at 6,500. I am thinking of pulling it for inspection, freshen and better oil pan.

When I do, I am debating valve spring upgrade to make sure it stays happy at 6,250-6,500 RPM. I am running a fast MM lobe flat tappet, .55" lift and 243@.050 duration with stock Ed springs. Comp 10 degree locks. I think the basic Ed spring may be getting marginal at higher revs in this setup. I'm debating a moderate double spring or the Comp beehive. Suggestions welcome.