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Author Topic:   Floating Valves
tlkdlw
Dirt Full Roller

Total posts: 42
posted October 21, 2005 07:12 PM  
Need to have a better understand on what valve float is and what causes it.Also how to prevent it or cure it.

Thanks Terry

rocket36
Dirt Freak

Total posts: 209
posted October 21, 2005 11:59 PM  
at high rpm, the lifter can jump (float) off the top of the cam lobe, thus the valving staying open longer than required.
the most common cause is due to inadequate spring pressure to suit cam profile & rpm or plain out way to much rpm.

James Ott
Dirt Maniac

Total posts: 131
posted October 23, 2005 04:52 PM  
The way I understand it is the valve is travelling so fast that lifter actually looses contact with the cam surface. The valve stays open longer than it should. But the real trouble is when the lifter slams back into the cam or the valve makes contact with the piston. Higher springs pressures will allow you to get more RPM before valve float occurs.

tlkdlw
Dirt Full Roller

Total posts: 42
posted October 23, 2005 10:15 PM  
Thanks guys that gives me a good understanding of what it is and how to avoid it.

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