cam vs. coilbind

[bang]

hey.

how many mm gab should i keep before coil bind? have coil bind at 22 mm lift. my heads flow up to 20mm is 2 mm clearance okay before coil bind?

[Stripped66]

Follow the manufacturer's recommendation. The clearance at coil-bind contributes to damping spring harmonics, so you don't necessarily want to increase this clearance significantly, especially if you're suggesting running 20mm of valve lift...that's going to require some serious valvetrain, so setup is not trivial (shimming the spring, using offset keepers, or cutting the spring pocket should all be considered to achieve proper clearance). 2mm is in the ballpark of what many manufactures recommend, but not knowing what springs you're running I couldn't say otherwise.

[bang]

running k800 and pauter 1,5 roller rockers.

[Stripped66]

K800 is the wrong spring for 20mm of lift.

[jaqo]

k-800 coil bind at 1.085
http://www.kmotion.biz/springdat.htm
http://www.kmotion.biz/instht.htm

[Udo]

K800 is the wrong spring for 20mm of lift.

I think the same. 20mm you need other springs. i have some nice PSI now but have no results

Udo

[Jonny Grigg]

What spring would you use with that kind of lift. When mocking up my motor this summer we ended up with 17mm lift, which was right on the knuckle of coil bind.... But my rockers measured out at 1.55 instead of 1.4 so have now gone to Pauter. I haven't mocked back up yet to see what I have got......