[RoyLeoGracie]

SBC: does anyone know if its' a big deal to use Lunati/Crower solid roller lifters in a gen 1 block with a hyd roller cam? What is the difference in a hyd roller cam compared to a solid roller cam other than the higher lift and longer duration generally found on solid roller cams. My current heads will not support over @.500 lift and I am using a stock converter for now.

Thanks,
Roy

PS, I got a great deal on some solid roller lifters I couldn't pass up and its' easier to measure for correct pushrod length with a solid lifter.

[Packard V8]

Yes, it has been done, always for reasons as wrong as yours. Solid cams have a gentle ramp to take up the clearance. Juice lifters stay tight on the cam all the time, so no clearance ramp. Since you have to have some clearance with solids- between .0005" and .009", depending on the cam profile and whether the heads and block are iron or aluminum - adjustment is critical and will have to be done often.
No, it shouldn't be done - bad science and a pain to keep the lifters adjusted on the knife edge. A couple of thou too tight and disaster happens; a couple of thou too loose and it is like the castanet tango under there. Some cam profiles in some aluminum heads will drive you crazy with the noise.
Maybe, you should either make a buck re-selling the lifters or buy the right solid roller cam. For every semi-successful runner there is a failure, sometimes a blown engine.

thnx, jack vines

[wmhjr]

There are people doing this for different reasons, and who will disagree with your assessment that it is not sometimes worth considering. I'm not talking chevies, but I would seriously disagree that keeping them in adjustment is either a pain or that they come out of adjustment easily. Even Crane and Bullit will tell you there are times that it may be worthwhile. BTW, lash in such a config on a poncho should be between .006 and .008. Of course, this may be off topic as the valve geometry is different between pontiacs and chevies.

[curtis73]

In general its a very bad idea. Without that lash ramp its just asking for trouble. A hydraulic lifter doesn't need that ramp, but putting solid lifters on it and adding lash will punish valvetrain parts. The lash takeup will be like hitting the whole thing with a sledgehammer. The constant hammering will make short work of things.

[RoyLeoGracie]

Thanks for your replies gents, nice to know I'm not the only one on this forum on a Sunday night! Curtis73 talked about a "lash ramp" on a solid roller cam. I imagine the solid cams may also be stronger than a hydraulic. It is clear I will need to use a solid cam. The difference between solid & hyd roller cams was my primary question and as I'm sure most of you know the staff at Jegs/Summit could not give me an answer.

Thanks,
Roy

[wmhjr]

OK, let's be accurate here, yes?

We all have opinions. We ought to be a bit more clear about stating something as pure fact when in fact it is an opinion. This is a perfect case.

Simply throwing solid lifters in on a hydraulic roller cam because you happen to have them is not a great idea. There has obviously not been specific thought as to the cam profile, the desired engine build, etc to determine what combination might work. So on that note, I agree that most likely the OP ought to swap out the solid lifters for hydraulic lifters. We have no idea of the cam that the OP has so at a glance it isn't a great idea.

That being said, let's also correct some other statements to show that they are opinions and clearly not necessarily factual. I respect the opinions of the other posters in this thread. We don't all have to disagree. But let's at least be open to the reality that these are just opinions based on individual knowledge and experience. And we all have different experiences.

There are other reasons to use solid roller lifters on a hydro roller cam. One might be concerns about valve float while still wanting the specific profile of a hydro roller cam - not to mention that solids in theory do make a bit more power (read recent mag article directly comparing solids to hydros). Not all hydraulic cams have the same profile. Setting valve lash to between .006 and .008 - so long as the rest of the build is correct - is not difficult and not in any way dangerous. Seat pressure doesn't need to be anywhere near where a solid/solid combo needs to be. It needs to be somewhat higher than in a hydro/hydro combo but not anywhere near as high as a solid/solid combo. In other words, the heads need to be built to do this. It does NOT "hit like a sledgehammer" and does NOT "make short work of things" - so long as the build is correctly designed. I can point to plenty of people successfully and happily running this combo for years. Crane and Bullet Cams can easily provide info on exactly how to properly set this up, and can provide clear proof that it's a viable solution. One would think that if there were not a very real and viable method for doing this, then the cam and lifter manufacturers themselves would caution you to never do it - instead of providing guidance on exactly how to do it, when, and why.

[F-BIRD'88]

You will often see solid roller lifters offered for sale "cheap" that appear to be a "good deal". They are cheap for a reason. They are all used up.
People that race with a racey radical solid roller cam know that the solid roller lifter takes a beating in race motor. When (Not If but when) they come unglued, often the motor is destroyed. So as preventative maintainence they change the lifters just like you would change oil. It is cheaper to change the solid roller lifters than wait for one to come apart and wreck the motor. Then, they sell the time bomb roller lifters to guys like you that don't know better and lookin for a good deal, to help offset the cost of new. Never buy used solid roller lifters.
No one ever sells good second hand solid roller lifters.

If your valvetrain is limited to .500" you cannot accomodate a roller cam anyways. You will need to upgrade the valvetrain. Get a good flat tappet cam and new flat tappet lifters.
The solid rollers on a hyd roller cam trick is used as a temp set up tp win a race only as it will allow a bit more rpm. It is not recomended to run it in that configuration for extended street time.

Now you know better......

[wmhjr]

You know, people should be very careful describing their opinion using words like "only" and a "trick".

There have been plenty of discussions, research and testing using solid roller lifters on hydro roller cams elsewhere - and discussed in great detail - for far more reasons than a "trick" or to "win a race". And in engines that run for years and years and years without a single rebuild or replacement of lifters. As mentioned specifically, Crane and Bullet will absolutely discuss the intricacies of this particular idea.

Also as previously mentioned, I also agree that solids on a hydro in this particular case are not recommended. There has been no thought to head and valve train build as part of a deliberate design using solids on a hydro.

[RoyLeoGracie]

Thanks guys, I had a great discussion about this today with a Comp Cams tech. All of you make great points based on personal experience and knowledge. There has been quite a bit of thought that has gone into this project and I learn more every day through continued research. The valve train will be good for .6oo lift ,however the heads may or may not "flow" at that rate. Flow testing will be done after I've completed the porting and polishing. The Comp tech said set the lash .004 to .008 and you will not have a problem especially with the BeeHive springs I am using in the assembly.
The key here is using the best parts and combinations you are able to assemble with the time, money and personal labor you have.

Thanks for all your info,

Roy

[woodz428]

I didn't read all the posts thoroughly, but I saw a lot of discussion regarding ramps...but none about the material of the cam. I think that you would wind up wiping the lobes pretty quickly. I know that many of the Ford Hydraulic rollers are still cast cam cores and solid ones "were" steel, since the cam and lifter material need compatibility the lobes wear aggressively. I have inspected several new engines, built by a prominent engine builder that followed the recommendations of the cam company( which by the way, changed with every tech that was consulted) that had lobes going south in less than 3000 miles...I don't consider that long term. At a 1/4 mile a run, if you lose, that may equal many years of service, but if you drive on the street ...that doesn't come close to a year in my cars.

[wmhjr]

Were these engines that had premature cam lobe wear running solid roller lifters on hydraulic roller cams using .006 and .008 lash and correct seat pressure, etc? I'm just curious about this. What were the actual builds?

I'm asking because this is the first time I've heard of it.

BTW, using Comp Cams as an example, both hydraulic roller and mechanical roller cams (for street/strip models such as Magnum) are made of the exact same Aust Tempered Ductile material. Only the full race cams are billet, requiring a different distributor gear.

[RoyLeoGracie]

One last note on this: if the metals are compatible, the lash is .004 to .008, and the dist gears work together then why all the fuss using a solid roller lifter no matter what the lift is? Logical thinking tells me the following: zero valve float, less friction and ease of establishing correct pushrod length use for correct valve train geometry. Other than setting lash I just don't see what the big deal is unless you're shooting for > .550 and 6500 rpm. If anyone can tell me what is wrong with this thinking please do, I am here to learn all I can.

Thanks,
Roy

[oldbogie]

Originally Posted by RoyLeoGracie

SBC: does anyone know if its' a big deal to use Lunati/Crower solid roller lifters in a gen 1 block with a hyd roller cam? What is the difference in a hyd roller cam compared to a solid roller cam other than the higher lift and longer duration generally found on solid roller cams. My current heads will not support over @.500 lift and I am using a stock converter for now.

Thanks,
Roy

PS, I got a great deal on some solid roller lifters I couldn't pass up and its' easier to measure for correct push rod length with a solid lifter.

This sounds like the same logic my wife uses when she see's a sale and buys clothes, shoes, purses or whatever that she has no use for, but she got them at a "great price".

I just get strange looks when I tell her it's money lost whether it's a good deal or not, if it's something you can't use.

Bogie