newbie cam question, dont beat me! ;)

[shaun]

I see a lot on these boards about cams and everybody is always refering to a solid, hydrolic, or roller cam. What is the diffrence between these types? What advantages/disadvantages does one have over the other? Pictures always help if ya got them!

[Craig]

solid and hydraulic flat tappet cams look like have a flat bottom that rides on the cam lobe.
http://www.jegs.com/photos/817rhlifters.gif
Hydraulic lifters require no periodic adjustment to the valvetrain. They have an internal adjustment if you will, that compensates for valve lash. Set 'em once and you're done.
Solids have to have a clearance set between the rocker arms tip and the valve stem. This has to be done periodically. These rev higher than a hydraulic cam.
Rollers, as the name implies have a small wheel that rides on the cam surface.
http://www.jegs.com/images/products/...3016_small.gif
These also come in hydraulic and solid with the same advantage/disadvantage as a flat tapett cam.
With the roller tip you have less friction at the cam/lifter interface. The roller also allows for a more aggressive cam lobe profile. In other words the ramp that opens the valve can be steeper and get the valve open faster because of the roller.

[shaun]

So when people are talking about solid, hydrolic, and roller cams they are talking about the lifters? why dont they just say that in the first place

[Hotcrusader76]

IMHO...
Stay with hydraulic for a reliable lake boat
Go solid to impress your friends with power
Go roller if you have money to spend....and again....impress your friends with power
As far as the finer details? Stay tuned...I am sure you're going to be in for a ride with that question from many of the heavy hitters here.
Good luck...
Note--I've run Hyd versions just fine....very reliable. My next motor is going to have a solid roller...but then again it's not an everyday lakeboat.

[Hotcrusader76]

Originally posted by Shaun
So when people are talking about solid, hydrolic, and roller cams they are talking about the lifters? why dont they just say that in the first place
Yes, lifers and the camshaft the compliments them...or is the other way around

[shaun]

Are ceritan cams designed to be used with a certian type of lifter? This would make sense then.

[victorfb]

yes. a cam that uses roller lifters is not compatable with a flat tappet. also a roller cam that used solid lifters cannot be interchanged with hydrolic lifters. all cams are designed for that application. so im told.
sorry for steeling your avatar shaun

[Moneypitt]

Be aware that roller cams are a different heat treat due to the fact that they don't have to match hardness with the lifters.(no friction by comparision to flat design) So, you will need a bronze distributor gear to prevent damage to the dist. gear teeth on the cam.....The main advantage to "roller" lifters is they allow extreme valve spring pressures that slam the valves shut at the higher RPMs. These same pressures with flat lifters WILL flatten the cam lobes very quickly. The advice about using Hyd. lifters in a mild river/lake boat is true..There are several quite "hot" grinds available from just about every cam grinder, and they are just about maintaince free. Any solid set up will need some maintaince now and then.........If in doubt, use HYD.....Moneypitt

[shaun]

Thanks for all the great info. Sounds like for my setup hydrolic lifters would be the way to go, unless i am able to find a good set of rollers for cheap.

[Foggerjet]

Not only do roller cams allow higher spring pressures, they require it. Roller lifters are much heavier than say a solid flat, so to keep from "throwing" the lifter off the cam lobe, a double or triple spring is req'd. I've seen race motors with 350+# of seat pressure, WOW.
fog