Valve spring diameter question

[Tommy]

The new trick flow aluminum double hump heads have two sizes of valve springs available, 1.460 and 1.470. I've looked at the specs on both heads and can't see a difference except for the spring. The heads with the smaller spring are more expensive and I'd like to know which spring is preferred and why.

Tommy

[x33rs]

The 1.460" spring package is a double spring (inner spring as well). Will have more seat and open pressure, however they don't list any spring specs.

The 1.470 spring package is just a single spring, no damper.

[Tommy]

Thanks, i completely overlooked that. Just compared specs again and I see it now.

Tommy