Difference between solid cam and hyd. cam?

[440valiant]

What it the difference between a solid cam and hyd. cam? Is one more for the street, and the other just for racing? If you get a solid cam what other things would you need(lifter, push rods). Same thing for hydraulic?

thanks:snakeman:

 

[needsaresto]

Hydraulic cam= Less maintenance,quieter operation,many trouble free miles but a less radical cam profile and limited rpms(6000-6500) due to valve float etc.Can be used with mostly stock heads/valve train.Btter suited to a daily driver.

Solid cam= more agressive profiles,constant valve lash adjustments and adjustable valve train,noisy valve train,much higher rpm potential(9000+). Need heads that breath extremely well (major porting).Best for weekend warrior or all out race car.

 

[demon seed]

Now that's a good question

 

[RedFish]

Now that's a good question

And a good answer above too.

 

[Petzschler]

Hydraulic cam= Less maintenance,quieter operation,many trouble free miles but a less radical cam profile and limited rpms(6000-6500) due to valve float etc.Can be used with mostly stock heads/valve train.Btter suited to a daily driver.

Solid cam= more agressive profiles,constant valve lash adjustments and adjustable valve train,noisy valve train,much higher rpm potential(9000+). Need heads that breath extremely well (major porting).Best for weekend warrior or all out race car.

DC's old hydraulic "cheater" cams will go to 8000rpm.

2 reasons why solid cams have more potential, and its all about the lifter:
1. The Lifter cannot collapse
2. The Taper on the Liifter Base (for a more aggresive lobe profile)
"mushroom" lifters are a perfect example of an extreame tapered base.

BOTH cam styles work extreamly well on the street, but in an all out drag car, SOLID would be the weapon of choise.
SOLID ROLLER is the ULTIMATE camshaft.. but that another story...

 

[moper]

The physical differences are as above. The description of where they each would be used IMO is not. The solid cam, due to it's lack of compaction at the beginning of it's lift and faster rates of lift for the same reason, Will make more torque at a lower rpm and more horsepower at a lower rpm point than an ideantical sized hydraulic. Also, perfornance hydraulic cams have certain lifter designs that are just as noisey, and require adjustable rocker arms too...

 

[rumblefish360]

In addition to the above by Needaresto. A basic way to look at the difference between the two lifter styles could be looked at like;

A Hyd. cam can be for as mello as mello gets up to a pretty hot package. Because the lifter can not get a as crazy cam profile as a solid dosen't mean the cam can provide excellent power or get a little crazy.

For best all around enjoyment, a Hyd. cam should be used.

A solid cam can also cover just what I said above on the Hyd. cam, but the profile can be ground for a more intense engine. Theres no reason a solid cam not perform as an everyday duty cam in a everyday car. It's been done for quite sometime. There RPM potentail is from idle to way over the top.

Solid cams are best somewhat radical to radical machines, serious street strip machines to race cars.

Solid cams will need different pushrods to suite the adjustable screw in the rocker. The rockers will be adjustable with or without a roller tip.

Hyd. cams can use both styles of rockers. You'll just need custom pushrods to work. It is no big deal.

 

[D-mailman]

I must disagree with the "constant valve lash adjustments". I know racers who only run the valves twice a season. I run mine more often than that but it isn't 'constant'. Besides,.. done correctly, it only takes about 20 min. to do it anyway, Two or three times a summer for a street strip vehicle would be about right. It is correct that the solid (mechanical) will make more power everything being equal. Comp Cam did a test a few years ago with a small Chevy, dyno test mule, but the results would apply to mopars also. They ground a hyd., solid and solid roller cam to the same specs. It was a moderate cam .550 lift range I believe. The solid flat tappet made 3% more power than the hyd. and the solid roller made 5% more. No doubt do to the reduced friction over the solid flat cam. If you don't mind adjusting valves, there is power to be gained by running a solid but with increased maintenance, a slight increase IMO. This is just FYI. The choice is yours.

Terry

 

[rumblefish360]

I'm with Terry on that. Valve lash adjustments shouldn't be so regular like oil changes. Good mention on the cam test.