over hydraulic...what things to I need to take into account when going with a soid roller cam? Any other parts have to be changed? And on an elementary level, why do the big horsepower motors go with the solid roller? Where does the advantage come in at?

 

Solid rollers allow highr RPM than hydraulics. In turn, they require (and can handle) substantially higher spring pressures. That requires a sturdier valve train, and timing set. In essence, the entire valve train needs to be upgraded. They will require periodic lash adjustments..... ~6K miles/twice a year.... and you will have to disable the knock sensor because of the noise associated with the beefy valve train and lash. You also have to be very careful in the selection of the lifters, because you can get into oiling problems that make them unsuitable for extended street use.

 

When using really high lift cams (.600+) which usually requires really strong springs, hydrolic lifters tend to collapse. At the same time, hydrolic lifters also can tend to do the oppisite, they can pump up and hang the valve open. Plus the solids are more accurate. Most sollid roller cams are billet steel due to their increased load they carry. You will loose the convience of hydro's, you will have to adjust them, and precisly.

 

beat me to it.... but agreed.

 

SR setups are considered to have more power potential, for the reasons given above. However, in the rpm range street motors operate in (up to 6,500rpm or so) a properly chosen HR has just about as much power potential as a SR without the hassles. Pretty much, you probably don't need one if you have to ask

Rich