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Big block hydraulic roller cams OK to 7000 RPM?

Posted By: PorkyPig

Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 05:58 PM

I see other brands supposedly getting hydraulic roller cams to run strong to RPM levels I always think require solid lifters in big block Mopars. Is this because those are generally small blocks with lighter valves, maybe using limited travel hydraulic roller lifters, beehive springs and stuff that isn't usually used (or available?) with big block Mopars?
Posted By: Dunnuck Racing

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 06:07 PM

Thats the main issues ,valvetrain weight and the proper lifters that don't deflect causing internal leakage. The correct oils help hydraulic lifters also,weather flat tapped or roller.
Keith
Posted By: CompWedgeEngines

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 06:08 PM

You need to use the right lifters, the right cam profile, and properly selected springs. Some Chevy guys going 7500 rpm. Everything has to be chosen accordingly.
Posted By: MR_P_BODY

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 07:12 PM

Quote:

You need to use the right lifters, the right cam profile, and properly selected springs. Some Chevy guys going 7500 rpm. Everything has to be chosen accordingly.



And the chevy guys use rev kits to help take
weight off the springs
Posted By: Streetwize

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 07:21 PM

my 517 Max wedge loves turning 7200 with a fairly healthy Bullet Hydraulic roller, iv'e had to trigger my tach shift light sooner because it gets there so quick. Pulls like a solid roller in this motor and throttle response is more like a comp eliminator car than a lot of even solid rollers.

My heads (Chapman/Zeus Stage VI's) also run the Race W2 billet hold-down blocks, I believe they are much more stable than cast in pedestals on big blocks at higher RPM. not sure it contributes significantly to the valvetrain stability but I'm quite sure it helps some.

Ron Silva I think runs the same Bullet HR (if it's not exact it's PD close) in his 501" small block and that thing revs like a banshee too. I'm real happy with the Bullet HR grinds, I think Bullet and probably the Cam Motion LS grinds are on the cutting edge of where you can get with a HR lobe and stabil valvetrain.
Posted By: MR_P_BODY

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 07:42 PM

Quote:

my 517 Max wedge loves turning 7200 with a fairly healthy Bullet Hydraulic roller, iv'e had to trigger my tach shift light sooner because it gets there so quick. Pulls like a solid roller in this motor and throttle response is more like a comp eliminator car than a lot of even solid rollers.

My heads (Chapman/Zeus Stage VI's) also run the Race W2 billet hold-down blocks, I believe they are much more stable than cast in pedestals on big blocks at higher RPM. not sure it contributes significantly to the valvetrain stability but I'm quite sure it helps some.

Ron Silva I think runs the same Bullet HR (if it's not exact it's PD close) in his 501" small block and that thing revs like a banshee too. I'm real happy with the Bullet HR grinds, I think Bullet and probably the Cam Motion LS grinds are on the cutting edge of where you can get with a HR lobe and stabil valvetrain.



Wise... whats the spring pressure on your Bullet HR
and if you dont might what are the specs... I'm thinking
I will change my 416 over to a HR vs the solid roller
in there now when I get that engine out of the Rampage
Posted By: Streetwize

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/08/13 08:24 PM

Mike,

Intake HR 316/370 264/179 CRS (symmetrical)
Exhaust HR 331/365 268/179 CRA (asymmetrical IIRC)

The 179 is the .200 lift durations

108 LDA
In +6 at 102

I gotta look up to see what I have on the springs, I can tell you they're actually mild Crane endurance solid roller springs I already had. just a bit over 500 over the nose if I remember right. These heads flow 335 @.500 and 361 @ .600 so I didn't need a ton of lift to make the target power. Was really surprised the first time we wrung it out, feels for all the world more like a hemi than a wedge.
Posted By: Streetwize

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 02:16 AM

Meant to add that the Chapman heads use 11/32 stem BbC length 2.25" valves that seem way lighter than a comparable BBM 2.14 or 2.18, also I'm running Ti retainers and spent a lot of time on setting up the ideal rocker sweep and lateral clearances, I think that helps a little bit too.

Also it's a b motor so the pushrods are comparably lighter and stiffer too, I think it all adds up, not to take anything away from
the bullet lobes.

Back in the mid 90's I crewed with a couple of guys in the early days of Pro 5.0 and way back then Bullet was cranking out all kinds of HR grinds for us to try, I think they saw the potential before most other cam mfgs did
Posted By: MR_P_BODY

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 02:56 AM

I have one Bullet cam but its a solid roller and I
am thinking of a hyd roller... and I want 7000 rpm
for the rest of my set up(I dont want to start changing
gears and conv)
Posted By: gregsdart

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 12:58 PM

The new Hemi uses hollow stem valves I believe, as does the 5.0 Ford motor for performance and high rpm stability in the valve train. If a guy wanted to take a hydraulic to the limit, there are a lot of things that can be improved, as mentioned. Beehive springs come stock on LS and New Hemis for that reason. Good (not cheap with the proper specs) valve springs are an absolute must. Titanium intakes, though expensive, would help a lot. Not going beyond needed weight in the pushrods, and finding nice light lifters all help.
Posted By: CompWedgeEngines

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 02:25 PM

You learn a lot about hydraulic roller set ups when working on boat engines. These guys that run the big twin and triple
screw 500- 572 ci boats put way more of a beating on the vslvetrain than anything here. The sustained rpm and occasional prop release will test the limits of everything. We arent really discovering anything new here, other than the typical Mopar builds,up until recent couple of years, hasnt considered hydraulic roller set ups. There was a fairly significant failure rate on some cheaper built big name lifters, so that scared some people. The guys that were using hi quality hyd roller lifters did not have issues. As stated early in my other post, its all about proper choice of components and application....
Posted By: MR_P_BODY

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 03:39 PM

Quote:

You learn a lot about hydraulic roller set ups when working on boat engines. These guys that run the big twin and triple
screw 500- 572 ci boats put way more of a beating on the vslvetrain than anything here. The sustained rpm and occasional prop release will test the limits of everything. We arent really discovering anything new here, other than the typical Mopar builds,up until recent couple of years, hasnt considered hydraulic roller set ups. There was a fairly significant failure rate on some cheaper built big name lifters, so that scared some people. The guys that were using hi quality hyd roller lifters did not have issues. As stated early in my other post, its all about proper choice of components and application....



What is considered a better hyd roller lifter that
can take a few extra pound of spring pressure(maybe 50-100)
Posted By: CompWedgeEngines

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 04:43 PM

PM sent..
Posted By: Streetwize

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/09/13 08:08 PM

Mine are about 6 yrs old and are (pre chapter 11) Crane units that I'm very happy with. Not sure they still make them or if the 'New' Crane make them to the same level of quality.
Posted By: CDoering

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/10/13 05:17 AM

I know Crane is at least making the big block lifters again as I bought some a few months ago.

Chris
Posted By: BradH

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/10/13 05:51 PM

If you expect to turn that sort of RPM and aren't restricted from using solid roller lifters, why would you want to run hydraulic rollers?
Posted By: 72Swinger

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/10/13 06:30 PM

Ive wanted to run a good HR on the street for a while but think its safer to go solid and run springs I know can take the RPM. At this point im thinking the Lunati Voodoo .600 solid roller would give me the most smiles per miles.
Posted By: Thumperdart

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/10/13 06:34 PM

Quote:

If you expect to turn that sort of RPM and aren't restricted from using solid roller lifters, why would you want to run hydraulic rollers?

EXACTAMUNDO.............I understand challenges and what not but step up or step back unless you plan on spending big bucks for the best of everything and that`s why I went w/Isky`s solid body lifters in an un-bushed block, .065 wall 3/8`s p-rods, h-sharp rockers and a custom solid roller grind I personally came up with on a liveable lobe design.........no brainer 8+ years later.
Posted By: Streetwize

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/10/13 07:43 PM

Hey I'm not choosing sides but the technology gap is shriking quite a bit. LS motors in what the low 8's with juicers and turbo's

I could have went solid roller but any more power on my motor would have been all upstairs and any more than I have would probably start eating up the stock 230 block. Like I said with My heads i didn't need any super high lifts (and the springs to go with it) plus I already had the lifters and springs left over from my old (somewhat milder) 508 RB.

From scratch I agree there's no real advantage except the occasional lash and maybe valvespring life if you've gotta have higher lifts/durations to get you to the power level you want. And as said earlier if you have a creatively plumbed turbo you might think twice about not having to do hours of plumbing removal and reassembly just to set lash (if you otherwise might not even have to )
Posted By: MR_P_BODY

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/10/13 07:52 PM

Quote:

If you expect to turn that sort of RPM and aren't restricted from using solid roller lifters, why would you want to run hydraulic rollers?



Maybe because I'm sick of hearing all the valve noise...
and I run a tighter lash than called for
Posted By: dodgeboy11

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/11/13 06:07 AM

Quote:

Hey I'm not choosing sides but the technology gap is shriking quite a bit. LS motors in what the low 8's with juicers and turbo's




Here's one without juice or boost.

http://www.youtube.com/watch?v=ltYLS_KZQV8

Car was running in the 9's when I was at the school.
Posted By: 451Mopar

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/12/13 08:03 AM

I was thing a hydraulic roller would be quieter too, but it seems to be just about as loud as a solid roller, or maybe I'm just hearing the roller rocker arms, rollerized timing gear, and roller thrust bushing?

I think a rev-kit where the springs press on the top of the lifter body would help if you want to run high RPM with a hydraulic cam?
Posted By: rickseeman

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/12/13 02:24 PM

I can't swear to anything in a big block but my Drag Pak Challenger has a hydraulic roller and you shift it at 7000. It also has very light springs. Big block valves would be heavier.
Posted By: gregsdart

Re: Big block hydraulic roller cams OK to 7000 RPM? - 07/12/13 02:40 PM

Time for a dyno test!! There is an article on a BBC motor, about 560 cubes? making 1,000 hp, and running hydraulic lifters. If those guys can do that, the Mope should be able to run 7,000 with the right parts. I would think a high ratio rocker would help significantly too.
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