1> are they worth anything more than hydraulic cams? i hear they are capable of more aggresive lobe designs, and lose less power since they can't pump up...

2> i hear all different answers behind how often you need to adjust the lash. some say "all the friggin time" and some say every other oil change... i was wondering who runs a solid lifter cam here and how often they find the need to adjust lash...

3> are stamped steel rockers sufficient with locking nuts? or should i really be looking up some roller rockers?

4> any tips for running a solid cam? how about break-in tips for a solid cam versus a hydraulic cam?

If theres a lick of truth to your signiture, i think you have other things to be worrying about. :eek:

tongue.gif That was COLD!

I've run a solid lift cam for over 25,000 miles and have checked lash often. Only had to adjust it twice on a few valves.

This is without poly-locks.

I even get better gasoline mileage with a solid than I did with a comparable duration hydraulic from the same manufacturer.

This is with a mild Crane solid.

For more info and my cam specs, see my web site.

PS: I agree with both of the above posts.

lol, i know. it's for the new motor i'm building. the last thing i have to decide on is what cam, gear, and stall i'm running.

i've heard the solid lifters are a little lighter than hydraulics,therefore allowing quicker ,higher revs and rpm potential.david vizard,a real racing and engine building guru has built and had great success with chevy racing and high performance smallblock chevy's using stock-style stamped rocker arms.he emphasises making sure you use the rocker balls with the oiling grooves.(the hemispheric-shaped doo-dad that the rocker arm adjusting nut tightens down on.)for anyone planning a smallblock project i highly recommend reading "how to build high performance smallblock chevy's on a budget."i learned more from that book than any i have ever read before.

I just bought a set of Elgin stamped rockers for my Son's 331, they look like a quality stamping and are thicker than stock. The grooved rocker balls were supplied and new nuts. About $39 from Competition products. I just hope they will work with the stud girdle we bought. The rocker studs on his heads aren't screw in or pinned so we went with the girdle to hold em all together. I'll measure the valve lift with these rockers and see how accurate the ratio is. Couldn't beat the price though. Bob

Another vote for stamped rockers here graemlins/thumbsup.gif
Grooved rocker balls are a must!

Crane has "Kool Nuts" specifically designed for stamped rockers. FOr any very agressive grinds ( I.e. Comp XS,etc), I would use a posi-lock like that.

5-10% more torque.

Better idle quality and rpm range for any similar grind.

Some degree of tunability using lash.

Need adjustment INFREQUENTLY, except during inital run in, which took 4-5 lashings to take a set.

I am swapping out a Comp XE262 hydraulic for a Comp XS262 solid. It won't be an apples-to-apples comparison because I'm also swapping heads, but I hope to report some positive results in the next couple of weeks. The duration and idle quality of the two cams is said to be the same, but the solid has a fair amount of additional lift, going .477/.488 compared to .462/.469 on the hydraulic.

but the solid has a fair amount of additional lift, going .477/.488 compared to .462/.469 on the hydraulic. When you subtract out lash, it will likely be a wash.

A 262 solid cam is a smaller cam than a 262 hydraulic cam. The reason is the lash. For example, given the same .050" tappet lift for both cams and 1.5 rockers with .025" lash for the solid, the hyd cam will lift the tappet .050" and the valve .075" (.050*1.5). The solid tappet @ .050" lift will open the valve .0375", half the valve lift of the hyd cam ((.050"-.025" = .025 at the point of contact with the valve stem)*1.5 = .0375). As you can see half the tappet lift, in this example, is "used up" taking up the valve lash. The crank will have rotated about 4º more with the solid than with the hyd before the valve starts to lift. The same thing happens on the closing side making the solid cam look to the engine as if it was about 8º smaller @ .050" tappet lift than a hydraulic cam of the same .050" tappet lift.

Being a smaller cam (same .050" for both), the solid will make more torque. I understand, however, even when allowing for this, by using a solid cam 8º larger @ .050", solids will make more torque and power. I haven't ran a solid since the 60's. I may dump the girl's cam I have now and go solid in the future. smile.gif

Thanks for elaborating Pat... I did not have time to type all of that! smile.gif

BTW... the XS262 has about 6 deg more @ 0.050 than the XE262 hydraulic, so in theory, it should ahve a similar powerband and make more torque as you've stated.

Originally posted by novadude:
BTW... the XS262 has about 6 deg more @ 0.050 than the XE262 hydraulic, so in theory, it should ahve a similar powerband and make more torque as you've stated. Yes, at .050 the XE262 is 218/224 and the XS262 is 224/230. Also, I disagree that lash will reduce the lift. At the top of the lobe, the rocker is obviously in full contact with the valve. There is no "lash" to subtract out once the rocker comes in contact with the tip of the valve.This is one reason why solids can make more power...the lobe design can be more agressive and give more lift.

Originally posted by Georgia69:
[QUOTE]Originally posted by novadude:
[qb] Also, I disagree that lash will reduce the lift. At the top of the lobe, the rocker is obviously in full contact with the valve. There is no "lash" to subtract out once the rocker comes in contact with the tip of the valve.This is one reason why solids can make more power...the lobe design can be more agressive and give more lift. Sorry, not true. Lash spec'd is always gross valve lift with a solid FT cam. You must subtract lash to get net lift. I've degreed solid cams and seen this with my very own beedy little eyes ;)

Also, .050 duration spec'd is net. In other words, cam card duration figures are net and lash is already taken out.

For example: My Comp 294s measured 252* duration @ .050 at the valve with 1.6:1 rockers --- slightly larger than the cam card. Net lift was only .536 a full .024" less than the theoretical lift with 1.6 rockers.

But back to the original question . . .

Every oil change is a good guideline for checking valve lash in a high performance engine. It may not have to be adjusted, but its a good idea to check. The cheaper the valvetrain parts the more you will have to adjust valve lash.

Yes, IMO a solid FT makes more power than a comparable hydraulic FT cam. The valve can be snapped open more quickly and solid lifters do not pump up at high RPMs. There are a lot more agressive solid FT lobes out there than hydraulic FT lobes.

"Also, .050 duration spec'd is net. In other words, cam card duration figures are net and lash is already taken out.

For example: My Comp 294s measured 252* duration @ .050 at the valve with 1.6:1 rockers --- slightly larger than the cam card. Net lift was only .536 a full .024" less than the theoretical lift with 1.6 rockers."

.050" duration is always speced at .050" tappet lift. The .050" tappet lift duration as speced on the card is correct. However, measuring at the valve stem, you'll see that the valve cannot come off the seat until the lash is taken up. The engine sees the cam as smaller even though the duration is correct at the tappet.

You are measuring with 1.6 rockers, in that case the .050" dur could be approximately correct. Higher ratio rockers increase duration at all points except seat timing.

[/qb][/QUOTE]Sorry, not true. Lash spec'd is always gross valve lift with a solid FT cam. You must subtract lash to get net lift. I've degreed solid cams and seen this with my very own beedy little eyes ;)
[/QB][/QUOTE]

Now that I think about it, it is obvious you are correct! My bad.

Pat, yes. good point, my cam card says 248* @ .050, newer Comp 294s cams say 250* @ 050 on the cam card. Same grind too. :confused:

And here's another oddity to ponder . . .

with a solid FT cam a higher ratio rocker will also effect seat duration . . . with a hydraulic cam it will not.

Here's why -- with a higher ratio rocker the valve lash (or slack) is taken up quicker so the seat duration increases with a higher ratio rocker. BUT technically one should compensate for a higher ratio rocker by increasing the valve lash set point so that the lifter "hits" the lobe at the same point that it did with the lower ratio rocker.

The looser the valve lash, the more a higher rocker ratio will affect the seat duration. The tighter the valve lash, the less rocker ratio will affect seat duration. So with a hydraulic cam there is no affect on seat duration because there is no lash, only pre-load.

For example:

.022" lash / 1.5 = .0146", .0146" * 1.6 = .0234". So if your valve lash is spec'd at .022" with a 1.5:1 rocker, you should technically set lash to .0234" with a 1.6:1 rocker, .0014" looser to compensate.

.014" lash / 1.5 = .0093", .0093" * 1.6 = .0149" so lash would need to be only .0009" looser with a 1.6 rocker on a "tight lash" cam.

Anyone's brain fried yet? :D

That makes sense. It could effect the seat timing the engine sees, of course tappet duration remains the same.

Changing lash does change seat timing, and duration throughout the entire valve cycling event. One of the nice things about a solid is the ablity to fine tune duration. Just have to stay with certain bounds. Don't want to miss the lash ramps.

There is another issue that should be addressed, the tappet lift point the duration is speced at by the mfg. Most chose an arbitrary lift to measure duration such at .020. The correct lift point is determined by the lash. Duration should be measured using the formula lash / rocker ratio + .004". This gives the tappet lift when the rocker just starts to lift the valve off the seat. A .022" lash should be measured (1.5 rockers) at .01866>". A .014" lash at .01333>". With 1.6 rockers at .01775" and .01275".

We frying some brains, now! :D