solid VS hydraulic lifters
 

What are the advantages or disadvantages of solid lifters over hydraulic?

carm, i'm pretty new to the fast boat world but can have built many a street and strip motor. you'll lose a little valve lift with hydraulic lifters over solid but you'll save your valve springs. solid are more for racing where every bit counts. i've only ever heard of one person running solid on the street and he was changing springs every 3 months. i've never heard of them in a boat motor besides maybe dragboating. roller hydraulic seem to be the way to go unless you like to pull valve covers alot. Eric

In a high performance application, it really makes no sense to consider anything other than roller lifters. The biggest difference between the hydraulics and the solids is more about cam profile- specifically the ramp. Lift is nice but if the valve is opening slowly, less total volume will enter the cylinder. Solids have (usually) a more aggressive ramp that opens the valve more quickly- that gives you more fully-open time in the rated duration. The downside is it's hard on everything. Lifters, pushrods, rockers, springs & valves all get the beating.

i've only ever heard of one person running solid on the street and he was changing springs every 3 months.

This is no way true.

I'm rebuilding the current motor. It' has solids with roller rockers. So what I'm hearing is I should replace the solids with hydraulic.

It's not the lifters, it's the cam profile. Hydraulics won't fare well with very aggressive lobe profiles. Even though the lift & duration specs can look alike, the solid opens much faster.

When you say solids, do you mean solid rollers?

Keep in mind, the purpose for using a roller lifter is to get the valve open and shut more quickly.

Just the rockers are rollers. The lifters are just plain solid lifters.

A hydraulic roller will give you a boost over solid-lifter cam performance without the hassle of solids.

There are plenty of guys here, including myself, who are running solid roller lifters. Most all of us, are not racers, just high performance everyday use. If the engine is set up properly, you wont have any troubles. Just have to adjust the lash once in a while.

PM or call a guy, RMBuilder on this board. He will answer your questions.