Please explain the difference between solid and hydraulic lifters.

I am going to rebuild, and want to know what the big difference is between the two types of lifters, thanks

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1981 Pontiac FB originally V6, converted to SBC (HEI), Performer RPM, Holley 750 Vac Sec., Chrome Dress up, True Duals, www.peikmusic.com/Projects.htm (http://www.peikmusic.com/Projects.htm)

Hyd's have a certain range that they can self adjust to compensate for wear. The cup the pushrod sits in floats on trapped oil that is force fed through a hole in the side of the lifter.

Solids have the cup sitting against a step in the lifter. Oil fed into the lifter just goes through it and up thru pushrod to rockers.

Solids can be designed with much more aggressive ramps on the cam lobes, so two comparable cams, one solid one hyd, the solid will make more power under the curve, and will rpm higher before floating the valves.

To make the same power with a hyd as a solid, you would need to get one with more duration, whick would kiss off some low end power.

But solids require occasional adjustment, which is why they aren't used much.

edit: use solid lifters only on cam designed for them, and vice versa.



[This message has been edited by angel71rs (edited September 04, 2002).]

So if I want a bad a$$ sounding car, can solids be daily drivers? How ofter do they need "adjusted", is it just the rockers that need spaced?

Thanks

<font face="Verdana, Arial" size="2">Originally posted by BamaZ28:
So if I want a bad a$$ sounding car, can solids be daily drivers? How ofter do they need "adjusted", is it just the rockers that need spaced?

Thanks</font>

Yes, matter of fact, I am also swapping to a solid. There were factory cars that came out with solid camshafts back in the 60's. So yes, they can be used as daily drivers. If you use polylocks on your roller rockers, valve adjustment will be maybe oce, or twice a year. If you need constant adjustment, that means you have something wearing out elsewhere.

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Speed-O-Motive 383 stroker kit,4 bolt 350 bored .030 over,TRW Forged pistons,Moly Rings,Comp Xtreme 284 cam,.540 lift with Crane 1.6 roller rockers,World Products Sportsman II heads, ported and polished with 2.02/1.60 valves, Comp guideplates,Edelbrock RPM intake,Holley 750DP carb,Hedman 1 5/8 headers to 2.5" duals and flowmasters,HEI with MSD6A box,TH350 with Hughes 3000 stall,4.11 gears.

Want a real fun cam? Pick one setup for solid rollers and get the accompanying lifters http://web.camaross.com/bb/smile.gif
You can get even MORE aggressive with lobe profile then without going longer duration...
The cam I picked for my 454 seems huge, but it makes monster torque in a wide, smooth curve.

Solids need adjustment every 3k-10k miles, some go a whole year without needing to adjust the valve lash. Springs can die early though, they will not last like hydraulic springs will.

So these ploylocks? Are they expensive and are the in summit or jeg's? I am looking for suggestions now on the solid cam. It will be in the 350 with aluminum heads. I want at least flat top pistons. I will drive the car maybe 25 miles a day. Thanks for all the help

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1981 Pontiac FB originally V6, converted to SBC (HEI), Performer RPM, Holley 750 Vac Sec., Chrome Dress up, True Duals, www.peikmusic.com/Projects.htm (http://www.peikmusic.com/Projects.htm)

Well, here is one way to look at it:
Tide = Solid
Tigers = Hydraulic
http://web.camaross.com/bb/biggrin.gif

<font face="Verdana, Arial" size="2">Originally posted by BamaZ28:
So these ploylocks? Are they expensive and are the in summit or jeg's? I am looking for suggestions now on the solid cam. It will be in the 350 with aluminum heads. I want at least flat top pistons. I will drive the car maybe 25 miles a day. Thanks for all the help

</font>Yes, they call them Koolnuts in Summit...
look at the Comp Magnum 282s solid cam...great street cam!



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Speed-O-Motive 383 stroker kit,4 bolt 350 bored .030 over,TRW Forged pistons,Moly Rings,Comp Xtreme 284 cam,.540 lift with Crane 1.6 roller rockers,World Products Sportsman II heads, ported and polished with 2.02/1.60 valves, Comp guideplates,Edelbrock RPM intake,Holley 750DP carb,Hedman 1 5/8 headers to 2.5" duals and flowmasters,HEI with MSD6A box,TH350 with Hughes 3000 stall,4.11 gears.

If your budget can afford it, get a hydraulic roller, best of both worlds
One more note on solids, they are noisier than hydraulics, due the lash required. Look at the CompCams tight lash series if you want a state of the art solid cam, that is not too loud.

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Texlurch - 68 Camaro-LT1 w/Hot Cam, TT & TIC coming soon!
" a little spray never hurt anyone, spank you very much!"

http://camaroz28.cardomain.com/id/texlurch