lifter tick?

[SteveSRT8]

As someone who has a hydraulic roller motor that easily revs past 7500 rpm in a flash I don't know why anyone would imagine that solid lifters are mandatory.

There's a few small displacement engines revving higher with hydraulics, they can yield all the revs you need...

 

[Trav]

Not mandatory but small displacement engines like bikes with hydraulics do not deliver the performance of mechanicals, they have a much lower (4,000 or more) RPM limit.
I guess we have to agree to disagree.

http://www.cranecams.com/bulletins_listview.php?s_id=11

http://www.popularhotrodding.com/tech/0712phr_hydraulic_roller_valvetrains/

http://www.compcams.com/Pages/419/camshaft-breakdown.aspx

 

[DBMaster]

"Agree to disagree."

 

[The_Eric]

I think that what Trav is trying to say, is that when things get REALLY HAIRY in the cam department, that solid is the way to go.

Last I knew the "practical" limit of a hydraulic lifter was 400-450 lbs of open spring pressure. With some of today's wild cam profiles, 600, 700, 800lbs open pressure are needed to control the movement of the valvetrain. I think some applications are going with even more pressure!

Still, for the majority of us, the hydraulic lifter is darned hard to beat.