Solid vs. Hydraulic Roller (Performance)
 

It is common knowledge that a solid roller will out perform a hydraulic roller at the cost of durability. The question is how much HP / Torque / Performance advantage does the solid really produce? I will use my motor as an example for the solid roller and let some of the engine guru's give opinions on how much less a hydraulic roller would produce. My motor is NA 598" with 10:1 compression. The heads are Dart 355 CNC with a match ported Dart single plane intake. The carb is a Nickerson stage 5 1250 Dominator and I use a 1" open spacer. The exhaust is CMI Sport Tubes, which are true headers and finally the cam is a 264/270 dur. @ .050" lift on a 114 LSA installed on 112 intake CL with .740" lift and .020" lash HOT. The motor has not been dynoed, but in the boat it seems very "happy" from 3000 to 6400 RPM. It has a decent idle and enough low end power for its application (23' cat). So, if the solid roller were replaced with a hydraulic roller what could be expected?

Craig

Re: Solid vs. Hydraulic Roller (Performance)
 

Craig,
What spec Hyd-roller are you you considering running? It would be nearly impossible to apples to apples baseline this solid roller to a comparable Hyd roller due to design considerations.
Bob

Re: Solid vs. Hydraulic Roller (Performance)
 

Good point Bob!! I really have no clue? It would have to be determined based on my motor and a marine application. If the hydraulic duration at .050" were very close to that of the solid roller my guess is it would be a poor idling cam due to the slower ramps requiring more seat to seat duration. I guess I am just looking for an educated guess as to how much difference exists between a properly specified hydraulic roller compared to a properly specified solid roller. I guess for now we can assume my solid roller is properly specified since the motor idles well and has very good power throughout the entire RPM range.

Craig

Re: Solid vs. Hydraulic Roller (Performance)
 

if your not going over 6500 i would stick with hyd roller but as you know the 7500 rpm passes that the AGITATOR made i think you know it has a solid roller seeya :drink:

Re: Solid vs. Hydraulic Roller (Performance)
 

The "741" sure won't get it done........ :rolleyes: I asked the various cam company experts about this for my old 632", consensus was a LOSS of 125HP :eek: over the solid roller I ran...of course lack of lift was the killer IMO. :drink:

Re: Solid vs. Hydraulic Roller (Performance)
 

I looked into the liquid roller cams and they all seem kinda whimpy by solid comparisons. I think you are too big to "not loose a lot", going backwards. I talked with a few cam companies and they start out real small.. I quiz them on the big stuff and they shriek. So for now I will stick with the solid roller.. well lets say I am going back to it. Cant keep a flat tappet cam in my motor, so wheels it is.. the axleless kind.. See if that works..

Re: Solid vs. Hydraulic Roller (Performance)
 

Dick,

I guess you have decided on Shubeck lifters.. I hope they work for you. We all know you deserve a break with cams and lifters lately.

Re: Solid vs. Hydraulic Roller (Performance)
 

Yeah Vinny,, thats the choice. I am a sucker for the new stuff. I ordered them a while back. Hoping to see them under the tree, but if not. Well the water is gettin hard here, so I have some time.

Dick

Re: Solid vs. Hydraulic Roller (Performance)
 

have you tried the crower 66291 with the high pressure pin oiling

Re: Solid vs. Hydraulic Roller (Performance)
 

Schubeck radius lifters make MORE power than roller lifters....... :p They are light and need much less spring. I witnessed on my old motor

Re: Solid vs. Hydraulic Roller (Performance)
 

???

Re: Solid vs. Hydraulic Roller (Performance)
 

I have no real intentions of changing cams at this point. I just like to bring this topic up occasionally to see if anyone can truly answer the question. I agree that there would be some significant performance losses in my application if I were to try a hydraulic roller. Now the radiused Schubeck deal is very interesting. I know JDNCA1 ran them and they dynoed very comparable to the solid roller, but he only put 4 or 5 hrs. on them before getting his new boat. Hopefully Mr. Gadgets has good results to report next fall and maybe this will be an option for all of us to consider. Thanks for the replies!!

Craig

Re: Solid vs. Hydraulic Roller (Performance)
 

Yeah!... let someone else be the guinea pig on those things... I'd like to know their longevity..... :D

Re: Solid vs. Hydraulic Roller (Performance)
 

Seeing as that you are maxing about 6400 RPMs then I would say you wouldn't see much difference in horsepower if everything else were the same. You would however spend less time in valve train maintenance every season if you used the hyd-roller.

Roby

Re: Solid vs. Hydraulic Roller (Performance)
 

Robyw1,
It may seem that way, but the characteristics of hydraulic vs solid lifters cannot be compared on an apples to apples basis. A hydraulic roller cannot open the valves as quickly as the solid so for the exact duration at .050" numbers the hydraulic roller will need more seat to seat duration. This holds true for durations @ .100, .200, etc. Realistically for a hydraulic roller to idle well the duration @ .050" is going to be something less than the solid roller's duration at .050, and the lift is going to be less as well. All of this obviously will have an effect on how the motor performs from idle to WOT. I just thought it would be fun to ask how much? Really the hydraulic roller must be chosen without considering the soild that is in the motor now. Size the cam for the motor and its application and see where it ends up. Since we all know the solid roller size it will be hard to not just select the largest hydraulic roller we can find, which will likely be too large for the application, but it may compare in numbers to the solid. Anyone out there have a proven strong performing hydraulic roller for this scenario?

Craig

Re: Solid vs. Hydraulic Roller (Performance)
 

.740 lift...those poor valve springs, are you cooling them with oil?

Re: Solid vs. Hydraulic Roller (Performance)
 

B4more,
I am not running spray bars for additional cooling. Net lift is actually only about .720!! :p These valve springs are made for endurance applications and so far after 15 hrs. they have only lost a few pounds on the seat. Time will tell, and if they make it to 50 hrs they will be replaced regardless of seat readings. :cool: 50 hrs for me is 2-3 seasons!

Craig

Re: Solid vs. Hydraulic Roller (Performance)
 

Which ones you runnin?
We're havin good luck with the Isky tool room golds...hyd cam 248/258-.607/.618

Re: Solid vs. Hydraulic Roller (Performance)
 

Isky Tool Room Golds # 9945. I have heard good things about all of Isky's springs. Nickerson did my heads and these are what he recommends. He feels I should be able to get 100 hrs out of these without a problem.

Re: Solid vs. Hydraulic Roller (Performance)
 

Thats good to hear...my guy Jason Saris says 200hrs for us. :cool:

Re: Solid vs. Hydraulic Roller (Performance)
 

I kinda meant everything else being the same as in other than valvetrain. I would predict the numbers would be very close if we wern't exceeding... say 6500 RPM

Roby

Re: Solid vs. Hydraulic Roller (Performance)
 

This is your engine. :D:D:D

Re: Solid vs. Hydraulic Roller (Performance)
 

This is your engine on pushrods :D

Re: Solid vs. Hydraulic Roller (Performance)
 

Any Questions?

Re: Solid vs. Hydraulic Roller (Performance)
 

That is one beat-up SBC!! Can you put your finger on the series of events that led to that? It almost looks like maybe the lifter siezed and held the valve open which hit the piston!! Ugly!! :D

Re: Solid vs. Hydraulic Roller (Performance)
 

I'm not sure it is all the same engine (although it might as well be) I did a search on Yahoo for blown engine pictures. Some of them were too scary to post :D

Roby

Re: Solid vs. Hydraulic Roller (Performance)
 

:eek:

Re: Solid vs. Hydraulic Roller (Performance)
 

Matching the camshaft to the engines application and rpm range is far more important then what type of cam used. Power gains or losses can be offset with this. Sure an engine may feel like its making power, but when one is tweaked the gains can be considerable.

Chris

Re: Solid vs. Hydraulic Roller (Performance)
 

The bigger the motor, the more it will benefit from a solid. 572" + and a solid will start walking away even @5000....hydralic just can't open and close the valves fast enough regardless of lift.

Re: Solid vs. Hydraulic Roller (Performance)
 

I totally agree Chris!! That being said if the correctly matched cam of each type were compared how much difference in performance? My 598" package was a proven combo that Nickerson uses on a regular basis. He claims dyno results from this package have ranged from 800 to 840 HP. According to WPM my boat needs 750 HP to do 110, and with this motor it does 115, which makes me feel like it is inline with what Nickerson claims. So is 800 HP attainable with a hydraulic roller all else being the same with this motor in some of your expert opinions? Would the accdeleration be comparable? Where will the hydraulic roller suffer compared to the solid? Appreciate all replies. This is a fun debate for me and I am really surprised nobody has any solid answers, only opinions!! :cool:

Re: Solid vs. Hydraulic Roller (Performance)
 

You can make 800hp using hydraulic rollers.
My engines are relatively mild 572's:
8.5-1, Iron Merlin heads, 8-71 TBS, no intercooler, custom grind Crane hydraulic roller cam

Running rich on the dyno (9.3 AFR)-
5,200, 6# boost (1-1 ratio): 754.9 hp
5,578, 7.07#=801.5 hp

5,400, 7.7# (5% over)= 798.5 hp.....
it'll spin to 6000

Due

Re: Solid vs. Hydraulic Roller (Performance)
 

Wette,
Yes it is doable with a hyd roller. Now that I know what your goal is power and MPH then yes. You may also what to consider running a hyd lobe profile and mechanical lifters. This gives excellent power production and since the opening and closing ramps and flank area is not as aggressive as a solid roller lobe you can run a lighter seat pressure, ie around 170# @ seat.

The 572 package I worked on a few years back made 725 HP @5200 with a hyd roller that was in the 250 range and it was onlya 9 to 1 engine.

There are no solid answers in this business, just goals to be reached. Each engine needs to be designed to reach that goal. You take a customer of mine that has to use flat tappet solid stuff with OEM 990 heads with a CID limit of 470. He gets 730HP to 750HP out those engines. Good numbers, but then you take a Cup engine that is 12 to 1 and 358CID limit and a flat tappet cam and they make 835 to 850HP. It is what you have to work with to accomplish the goal.

chris

Re: Solid vs. Hydraulic Roller (Performance)
 

Craig,
I have the dyno sheet on RLW's N/A 540, 305 CNC chamber AFR, 1050 Nickerson, Hyd-roller 236*/240* @ .050" .625"/. 630" on 112*
700.9 Peak TQ @ 4900......1.3 lb/ft per CID
718.4 Peak HP @ 5900.......1.33 hp per CID
Translate that to 598 CID
777.4 peak lb/ft
795.3 peak hp
It would appear possible that with the proper component changes 800 HP is possible
The acceleration would be close up to peak TQ for the Hyd-roller (5000 RPM)
The .050” numbers are not as spread as would first appear due to the fact that you need to pull approx 8* duration at the valve from the solid to account for lash.
The significant advantage of the solid is its ability to maintain Dynamic Valve train Stability under conditions the hydraulic is limited due to:
Plunger deflection
Insufficient spring force
component weight
lofting
RPM limitations/lifter collapse
Roller lifter rate of rise per * only limited by side loading of lifter in its bore.
Bob

Re: Solid vs. Hydraulic Roller (Performance)
 

Here is what my friends 588’s made with 9:1 compression and dart iron heads and hydraulic cam. I do not understand any of the #’s other than the hp, rpm and torque.


RPM CBTRQ CBPWR FHP ME% FA+FB BSFC
4600 725.3 635.3 133.7 81.9 256.6 .44
4700 728 651.5 139.3 81.6 271.2 .44
4800 724.7 662.3 145.9 81.2 274.9 .44
4900 730 681.1 152.6 80.9 285.4 .44
5000 724.4 689.6 159.6 80.1 281.3 .44
5100 724.3 703.3 166.5 79.8 285.7 .44
5200 722.4 715.2 173.8 79.3 291.9 .44
5300 722.6 729.2 181.1 79 293.6 .43
5400 721.9 742.2 189.5 78.5 304.1 .44
5500 723.8 758 198.6 78.1 304.7 .43
5600 720.5 768.2 207.8 77.5 321.6 .45
5700 715.1 776.1 217.3 76.9 328.2 .45
5800 709.1 783.1 226.9 76.3 334.9 .46
5900 703.8 790.6 236.8 75.6 342.7 .47
6000 690.8 789.2 246.9 74.9 350.7 .48
6100 683.7 794.1 257.6 74.1 351.8 .48
6200 680.4 803.3 269.6 73.8 361.1 .48

Re: Solid vs. Hydraulic Roller (Performance)
 

Thanks for the info gents!! Boatless can you find out the particulars of the cam used to make those numbers? Thanks!

Re: Solid vs. Hydraulic Roller (Performance)
 

He purchased the engines second hand in a boat and they had the dyno sheets. He like me, doesn't know squat about them other than what the dyno sheet says.

When you say "Translate that to 598 cid" do you mean using all of the same components OR adjust the components accordingly to fit the larger displacement? Thanks, Chris

Before I met Rudy Dryden our present motor builder in Wilmington DE, I would never have considered hydraulic rollers.
Our previous high hp applications for or over 25 years including my Pro mod race car engines always ran big solid cams.

At this point I see no reason on a blown boat application to run a solid lifter cam with higher spring pressure and lash beating the valve train to pieces.

By using higher than recommended spring pressure ,the proper lifter as well as the correct pre load we get more than 3 times the longevity than previously attained with solids and still spin our 565CIs with high Helix 1471s past 6500 rpm's at will ,and make over 1250hp on pump gas along with Methanol injection which comes in at 8lbs of boost.
I know another well known boat engine guy that is now running hydraulics on his big stuff as well.The down side for the builder is just like running big fat jets in your 2 circuit Dominator is that they don't get to tare them down every season with washed down cylinders and beat up valve trains.

WOOOOAAAAHHHHHHH.

Every one of you guys is working to the extreme on every application that you are posting.

There is not one apples to apples application.

Solid lifters whether roller or flat tappet will yield better horespower or torque, and you know it, based on equal comparison of lift vs. duration on the same cam. on the same CI.

Problem is, no engine builder will waranty solid anything because of need for maintenance.

Work on that argument for a little while.

I am not looking for the extreme, I just want to build somthing similar to a Hawk 750 that will run for 500 - 600 troublefree hours with normal maintenance. Personally I don't really care about making 750 hp I just want a high torque curve from a 588 or 598"motor that will be happy propped to turn 5400 - 5600