[Skip Fix]

Darby I understand where you are at,and why, just questioning those that start off doing it. As Tom V has said "engineers do things for a reason" must be a reason the cam guys usually use a SR on a SR cam and HR on a HR cam, or a SFT on a SFT cam etc.

The hydraulic lobes generally don't have the "lash ramps" built in so act more aggressive on the ramps but a true solid can be even more aggressive. I know my first solid roller idled with much more vacuum than a much small HFT cam.

[grandville455]

Understand, I think it is just the fact that solid rollers make more power would be my guess?

[BruceWilkie]

Hydraulics roller or flat are limited in ramp rate primarily because of the hydraulics.

Solids, roller or flat use a lash ramp to gradually absorb valvetrain slack. Hydraulics are more like shock absorbers, but they cant be pushed as hard or they begin to collapse. Main reason you cant run as steep of a ramp with a hydraulic.

The steeper the ramp the sooner you are into higher flow area of your heads.

Lash ramp on a solid also is designed to set the valve down on its seat as gently as possible. This helps control valve bounce at high rpm. Again the hydraulics ramp rate is gentle and slow on the closing side as well to prevent valvetrain separation and lifter pump up. By design it has to be slower than a solid.

Although its done fairly often, using a solid lifter on a hydraulic lobe will tend to be noisier and a bit harder on the lifters and valve stems in terms of wear/tear. As mentioned the lash ramps are specially ground to close up lash at a smooth rate on opening and open up lash at a smooth rate on closing side. Functionally doing what hydraulic lifters do on a hydraulic profile.

Excess lash on a solid or hydraulic is hard on valvetrain parts because you remove the cushion of the lash ramp or hydraulic device.

Solids can run lash tighter than specified (right up to point valves dont close 100% and get burned) without mechanical issues. Its generally suggested not to increase lash by more than .004" max or you risk valvetrain damage.

That brings the question ...what is really safe lash if using a solid on a hydraulic profile? Answer is... PROBABLY more than.004", only because the hydraulic profile has a gentler ramp rate than a solid profile has after its off its lash ramp. (And tighter you go the greater risk of burning a valve)

My advise... spend the extra now for the solid roller. Even a street SR cam will be a gain. More often than not better everywhere in the process. Bullet Comp or Erson all have some nice lobes to chose from.

[ponjohn]

Originally Posted by BruceWilkie

Hydraulics roller or flat are limited in ramp rate primarily because of the hydraulics.

Solids, roller or flat use a lash ramp to gradually absorb valvetrain slack. Hydraulics are more like shock absorbers, but they cant be pushed as hard or they begin to collapse. Main reason you cant run as steep of a ramp with a hydraulic.

The steeper the ramp the sooner you are into higher flow area of your heads.

Lash ramp on a solid also is designed to set the valve down on its seat as gently as possible. This helps control valve bounce at high rpm. Again the hydraulics ramp rate is gentle and slow on the closing side as well to prevent valvetrain separation and lifter pump up. By design it has to be slower than a solid.

Although its done fairly often, using a solid lifter on a hydraulic lobe will tend to be noisier and a bit harder on the lifters and valve stems in terms of wear/tear. As mentioned the lash ramps are specially ground to close up lash at a smooth rate on opening and open up lash at a smooth rate on closing side. Functionally doing what hydraulic lifters do on a hydraulic profile.

Excess lash on a solid or hydraulic is hard on valvetrain parts because you remove the cushion of the lash ramp or hydraulic device.

Solids can run lash tighter than specified (right up to point valves dont close 100% and get burned) without mechanical issues. Its generally suggested not to increase lash by more than .004" max or you risk valvetrain damage.

That brings the question ...what is really safe lash if using a solid on a hydraulic profile? Answer is... PROBABLY more than.004", only because the hydraulic profile has a gentler ramp rate than a solid profile has after its off its lash ramp. (And tighter you go the greater risk of burning a valve)

My advise... spend the extra now for the solid roller. Even a street SR cam will be a gain. More often than not better everywhere in the process. Bullet Comp or Erson all have some nice lobes to chose from.

Bruce-

There is no doubt that a SR grind will improve power but at what expense to valve springs?

Can a street SR grind be run long term without changing springs every season?

[Cliff R]

Just a couple notes on solid roller to HR comparisons.

Two examples, no names given, as both customers read these threads, but don't post on here.

One of them was using the Old Faithful grind from SD, and was talked into a "custom" flat solid roller on a 110LSA from one of the Vendors. It was considerably bigger at .050", but I don't remember the exact cam specs, or the advertised numbers.

He did the swap, and all he got for his efforts was degraded idle quality and not quite as user friendly right off idle, cruising, etc. Ran about the same ET and MPH as the OF cam. Needless to say, he was quite disappointed as it was a very expensive swap.

Another customer was running a solid roller in the 240 @ .050" range, 248 come to mind but it could have been 242. In any case, it was also on a 110LSA, and the owner was taking steps to make the car a bit more street friendly.

This included the addition of an OD transmission, swap to Q-jet over the big custom Holley, etc.

He swapped the SR for the Old Faithful cam, as part of the effort to "de-tune" the set-up. It ran the same in ET and MPH as the larger SR. He noted that the engine idled better, and drove better right off idle, cruising, etc. Beyond that, nearly as he could tell, no difference in power production anyplace.

Morel of the story, the solid roller needs to be chosen considerably larger than the HR, to get the same thing done. I'd estimate at least 10 degrees, if not closer to 15 degrees @ .050"......FWIW.

I would also add here, that Dave at SD has one customer who logged over 15,000 street miles with the "hybrid" set-up, no issues. This is what made me want to give it a try, and the fact that my last engine had a built in "rev-limiter" using the HR's. Jeff Kauffman at KRE told me the same thing about the HR's. They make great power, but he sees them start to go "funny" on the dyno right around 5800rpm's with standard HR lifters and typical valve train weight that we use with these engines.......Cliff

[slowbird]

Originally Posted by Cliff R

Just a couple notes on solid roller to HR comparisons.

Two examples, no names given, as both customers read these threads, but don't post on here.

One of them was using the Old Faithful grind from SD, and was talked into a "custom" flat solid roller on a 110LSA from one of the Vendors. It was considerably bigger at .050", but I don't remember the exact cam specs, or the advertised numbers.

He did the swap, and all he got for his efforts was degraded idle quality and not quite as user friendly right off idle, cruising, etc. Ran about the same ET and MPH as the OF cam. Needless to say, he was quite disappointed as it was a very expensive swap.

Another customer was running a solid roller in the 240 @ .050" range, 248 come to mind but it could have been 242. In any case, it was also on a 110LSA, and the owner was taking steps to make the car a bit more street friendly.

This included the addition of an OD transmission, swap to Q-jet over the big custom Holley, etc.

He swapped the SR for the Old Faithful cam, as part of the effort to "de-tune" the set-up. It ran the same in ET and MPH as the larger SR. He noted that the engine idled better, and drove better right off idle, cruising, etc. Beyond that, nearly as he could tell, no difference in power production anyplace.

Morel of the story, the solid roller needs to be chosen considerably larger than the HR, to get the same thing done. I'd estimate at least 10 degrees, if not closer to 15 degrees @ .050"......FWIW.

I would also add here, that Dave at SD has one customer who logged over 15,000 street miles with the "hybrid" set-up, no issues. This is what made me want to give it a try, and the fact that my last engine had a built in "rev-limiter" using the HR's. Jeff Kauffman at KRE told me the same thing about the HR's. They make great power, but he sees them start to go "funny" on the dyno right around 5800rpm's with standard HR lifters and typical valve train weight that we use with these engines.......Cliff

We run typical valvetrain parts & it peaks at 6200-6300 & sees 6700-6800 in the 1/4. Hyd lifters work just fine for us. Not saying we wouldnt see a gain going to sr lifters but at this point we see no need to.

[grandville455]

Originally Posted by slowbird

We run typical valvetrain parts & it peaks at 6200-6300 & sees 6700-6800 in the 1/4. Hyd lifters work just fine for us. Not saying we wouldnt see a gain going to sr lifters but at this point we see no need to.

Brian, what kind of spring, and spring pressures u running? U using light valves and ,retainers too? What size pushrods?

[tom s]

I have told this story before but will tell it again.Some years ago when I built my first RA V engine Comp had just come out with their high lift hyd roller cam.I bought the complete cam and kit through Reath Automotive who was building the engine.After some conversation with Joe Reath and others I called Comp and talked to Dean Harvey and asked if they were OK with the setup running over 6500.He said he would get back to me.After a day or two he called back and had us send the complete kit back and sent us solid rollers and springs and instructed us to set them up at 200 on the seat and set them at 6 thou and the rest is history.This was maybe 12 years ago.I have been doing it that way ever since.Now after many years past the fact have been proven by many that you can indeed run the hyd roller lifters with heavyer spring rates and and make HP to the 7000 range.Im going to pull my solid rollers and put hyd in with 180lb seat pressure.The reason is im driving the cars many more street miles now that im retired anddont want to abuse the solid rollers.A few years back I got lucky on a tear down to find one lifter was going away and was just starting to touch the cam.I replaced them and have been just checking them a little more often.FWIW,Tom

[Steve C.]

Example mentioned by Cliff...

"He swapped the SR for the Old Faithful cam, as part of the effort to "de-tune" the set-up. It ran the same in ET and MPH as the larger SR. He noted that the engine idled better, and drove better right off idle, cruising, etc. Beyond that, nearly as he could tell, no difference in power production anyplace."

The solid roller was a XE grind with 242/248 degrees duration. Weight was added to the vehicle with all the changes. No back-to-back performnce testing was conducted between the two cams that I am aware of, it might of run slower with only the cam change, we won't know. The improved idle resulted in the change to a wider lobe separation, the previous 110 lobe separation was not harsh by any means. Some might suggest the change to the Q-jet had its effect on the off idle response over the Holley carb He now has put air conditioning on the vehicle, changed from a 3.89 gear to a 3.50 gear (Ford 9-inch), improved the exhaust system ... he is a happy camper. OH by the way... he is running upwards close to 200 poundes seat pressure !!



.

[grandville455]

We'll we will find out soon enough here with mine , I also only run the ferrare 5000 series valves,and they and Dave both said not to push them with too much open or closed pressure, I will be switching to some titanium retainers to help this deal out also.

[slowbird]

Originally Posted by grandville455

Brian, what kind of spring, and spring pressures u running? U using light valves and ,retainers too? What size pushrods?

Comps beehive springs with their retainers, Ferrea stainless valves, 5/16 pushrods I believe ( cant remember for sure). Spring pressure around 170

[slowbird]

Sorry engine now has 3/8 pushrods

[grandville455]

Running quite a bit of lift? Guessing u run the better 6000 series valves too?. I had taken a look at these comp beehives, 26056-16 Kinda lift restricted tho

[Steve C.]

Beehive valve spring. Higher RPM With Less Spring, Means More Power and Reliability.

David Vizard has run a Big Block Chevy valvetrain mass with a XE solid roller with 242 at .050" to over 6000 rpm ( 6200, if I remember correctly) with a Beehive spring at 150 lbs seat pressure.



.

[grandville455]

Well since I am going to use a titanium retainer I should be good to 6500, Dave told me before that with just upping the pressure and running my chrome moly retainers I would be good to 62-6300 .., He has a great luck with the these cranes and titanium retainers, cliff runs the same setup. But I would bet he has less pressure than what I do now, cause i just checked my 4 yr old springs and they were only 120@1.800! Granted I run more lift than cliff , or I did with those springs, so it may have killed them some more, but I bet he doesn't have 150 on the seat, I would bet he is close to my current new springs of 130@ 1.800 being his are 4 yrs old also, But He hasn't raced near as much as I have either in those 4 yrs so who knows, I guess we won't know til he checks them

[Ron H]

Darby, I went 4 pages in and then skipped to here.

Why not get an actual solid roller cam and springs to match, lifters and pushrods?

No point staying with the hyd cam and trying to match springs to fit it. For the cash, the gain you will see from a solid roller cam will be well worth it compared to the minor gain you will see changing all this stuff and staying with a hyd roller cam profile.

http://forums.maxperformanceinc.com/...lid+roller+cam

The first cam listed here will still be streetable and run much better than the hyd will. You are buying the other parts anyway...

Oh and 4200 stall should be fine with it as well.

[Ron H]

And if you actually want to step up to the plate and run into the 9's.
http://forums.maxperformanceinc.com/...lid+roller+cam

[grandville455]

Ron It all sounds good, but I only have the 5000 series valves and I was told not to push them with spring pressures that a true solid roller will need, If I decide to turn these heads into more over the winter Dave will upgrade all the stuff then, til then this is what i got and am going to run.

[Torment]

Originally Posted by ponjohn

Bruce-

There is no doubt that a SR grind will improve power but at what expense to valve springs?

Can a street SR grind be run long term without changing springs every season?

Not asking me... but yes. Keep the lift in check and buying top quality springs and you should have very dependable results.

[BruceWilkie]

Originally Posted by ponjohn

Bruce-

There is no doubt that a SR grind will improve power but at what expense to valve springs?

Can a street SR grind be run long term without changing springs every season?

Alot depends on springs chosen and to some degree the profile. Mystic is running a .440 hi torque lobe and 1.7 rockers with Manley Nextec springs. More strip than street(1.5 seasons iirc), 2nd season went from 1.7 rockers to 1.8's (.792 lift) same springs. Dont know if he has neded to change them for this season or not. PAC springs also noted to live even longer life than Nextec or so I've heard.

Nextec(Manley) selection does have springs suitable for lower lift "street" sr profiles. In both "Nextec" and "Manley" spring selection catalog. Alot of circle track racers run Manley or PAC.

Kaase installed Nextec springs on the heads for the Ford I built. Claimed he got great service life. Good enough for me.