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Tailites
11-21-2014, 09:42 AM
anybody done any research on HP losses thru the valve train?

need to find out how much HP is required to run the valve train on a 302

tulowd
11-21-2014, 10:01 AM
anybody done any research on HP losses thru the valve train?

need to find out how much HP is required to run the valve train on a 302

Don't think it is significant when compared to ring tension/friction, oil friction cavitation on the crank, blower drive losses etc.

Lightening the moving valvetrain (lifters, pushrods, valves, retainers etc) by one gram adds app 50 rpm potential according to some NASCAR and other engine building blogs I ve read.
ie) Edelbrock undercut stainless steel 2.05" intake valves weigh 118g each
Ti versions for the same size and height weigh app 80g each
38g x 50 = 1900 rpm potential

Retainers are cheaper to lose weight, altho not nearly as much

If you are talking about frictional losses, I would think hydr roller would be the lowest, since that's what the OEM s are using for efficiency and emissions.

Tailites
11-21-2014, 10:35 AM
yep...was thinking cam ramp rates & springs mostly...not weight so much

reason why I asked...its interesting how easy the engine turns over

when theres no cam in it...so there has to be considerable HP loss just to move the valve train

tulowd
11-21-2014, 12:50 PM
hmmmm I wonder.....maybe cause all the valves are staying closed all the time, lol

ie) you're converting to a 2 stroke this way