i just want to know what is the difference between these two cams and what is the ideal usage for each??

y

A 'solid' cam uses a 'solid' lifter. A hydraulic cam uses a lifter that has an internal cylinder that holds the rocker/valve clearance to 0. The advantage to a solid is that it weighs less and thus, all other things being equal will rev a little higher. The advantage to hydraulic is low maintenance.

Additionally, the solid provides more accurate valve timing, quicker valve acceleration, and can 'ride' a more intense lobe than a hydraulic cam. All told, you gain maybe 5-10% torque with a 'high-maintenance' :rolleyes: solid flat tappet. Use to have a link to n2performance where there was an excellent piece written on solid v hyd camshafts. After reading it, there is no reason to not use a solid grind in anything that is performance oriented , except sloth.

Well, I'm sorry that is not correct. There is still very few small solid grinds for your typical 8.5-9:1 street motor. Harold has some small SBC grinds, and if Lunati thinks there's a demand for them, I'm sure they'd roll out a line of 250-270 duration solid cams that would be tremendous street cams.

Think that for Comp cams users, it would be really interesting to see the difference in their solid and hyd XE grinds. I recall a magazine article some time ago, and the difference between a solid and hyd cam was only a few ponies in a 350. That shocked me. Would have guessed more. Don't recall if the test was flawed, but I would have expected more.

I was a little surprised on my hyd roller to solid roller swap, wasn't as much power there as I thought. Not sure if it was the cam itself, or what, but.
The guy doing the swap did say something quick to the tune of "if the cylinders were getting filled before.." so maybe the power difference wouldn't be that great unless you had a woefully inadequate hydraulic in there before.
That being said, I like the feel of the solid so much better.. Better sounding, revving, feeling, alot smoother For a limited use vehicle, I like it better so far.
But, I don't know if I'm die-hard enough to need one. "set it and forget it" has its appeal too..

I know some will disagree with me here, but IMHO you really can't go wrong with a good grind that is correct for your application whether it is hyd. or solid, solid has a few benefits, but hyd. is far less work.
This sort of question I would probably base on how much you drive the car, but that is just me.

matt

Gene,

I read that test "hydraulic/solid" and it was flawed. They used "advertised" duration matches giving the hydraulics an edge and closing the results to near 0.

I've learned through the years that in every comparison I've seen a magazine do, there is usually some flaw to skew the results toward what the author wanted to prove. Build the combo so the caparo part fixes the mismatch.

Ditto Greybeard on that big time too!!!

I LOVE THEM APPLE'S to ORANGE'S TEST'S!!!

pdq67

and remember that when they degree a similar pair of cams and say there's little or no difference between the solid FT and the hydraulic FT they are using a SOLID FT lifter to degree the hydraulic cam!! The compression of a hydraulic lifter is never seen while degreeing.

Also, lash effects seat duration significantly with the solid FT cam. When I degreed my Comp Magnum 294s the adv duration was in the mid-280* range while .050 duration was just over 250* :eek: (cam card specs 294* advertised, 248* @ .050)

If you were to compare that to the 292H (the hydraulic cousin of the 294s) you'd find the hydraulic cam has more seat duration and less 050 duration.

Solid FTs are just plain more agressive! They get the valve opened quicker . . .