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Old 11-24-2015, 07:31 AM   #39 (permalink)
oldtamiyaphile
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If reducing friction is the goal, what about roller rockers? I understand they aren't available/ won't work for Geo Metros (and OHC engines), but they would achieve the desired results, no?

Quote:
Originally Posted by Old Mechanic View Post
Maybe they should go back to the suction operated intake valves. Talk about low spring tension.
F1 engines use pneumatic valves. No springs.

Also, in my Fiat, the valves are hydraulically opened, the springs only close the valves, essentially halving the amount of time the springs are exerting friction on the cam (and friction is going to be minimal during the closing phase).
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Last edited by oldtamiyaphile; 11-24-2015 at 07:38 AM..
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