Roller Rocker Question

[moparmaniac59]

Hey folks,
I am at a loss for making a decision here. I am putting together my 543 stroker and need to choose a set of roller rockers to go with my Cam Motion (custom grind) hydraulic roller cam. I am using a set of fully ported Stealth heads (440 source). I value the opinons here and have heard good and bad on using the needle bearing roller rockers vice bronze bushing type roller rockers. Should I use them (needle bearings) or not. What's a good choice? Harland Sharp, Comp, Crane, Lunati, Proform ect?? Aluminum shafts/rockers vs steel? The more I look, the more choices I see, the more I become DUH??? It seems the more expensive sets have needle bearings. I am basically building (as my machine shop builder puts it) a "grunt" motor. About 600-650 HP street/strip motor with about 80% driving being street. I am trying to keep the cost down, but don't want to be rebuilding it because I used a cheap $400 dollar set of rockers when I could have spent $600 and gotten twice the quality. I guess I've said enough to figure what I am looking for. Thanks for any input!! Jason, just sell me your set up!!!!


                                             Matt B.

[bb71challenger]

For the street you want longevity with your rockers so I would get the comp cams steel ones. There are other good choices but for peace of mind I would get steel.

[moparmaniac59]

Thanks. What about needle bearings vs bronze bushings?? Is it true about the "hot spots" and uneven loading with the needle bearings??

[Chryco Psycho]

from an engineering stand point needle brgs make no sense to me you still have a film of oil in between the 2 surfaces so you will not free up power with reduced friction & you minimize the surface area from probably approx 1sq" to 100th of that , I have seen hard shafts with major grooves in them from using needle rockers , ........ nothing about this makes sense to me especially when you add in the hassle of fishing out needle brgs from an engine when one fails
 I have always used bushed rockers & steel or Iron for street use not Alum

[moparmaniac59]

I tend to agree with ya Neil. I am a machinist  by trade, but I work marine equipment. A roller can reduce friction (thus a roller cam) but with the rocker you definitely loose surface area. I (after much debating) went with the Hughes Racing cnc billet rockers and shafts. Looks like good stuff. I hope so!!


                                            Matt B.

[The Cuda Guy]

For the street you want longevity with your rockers so I would get the comp cams steel ones. There are other good choices but for peace of mind I would get steel.

 

[nivvy]

Harland Sharp ....... Hands down....... They have Caged needle bearings..... at 600+HP parts failure can happen with anything!

I still cant believe no one said about what spring pressure you will be running....... 

Can you guess which "bushed" rocker this is 

[The Cuda Guy]

Harland Sharp ....... Hands down....... They have Caged needle bearings..... at 600+HP parts failure can happen with anything!

I still cant believe no one said about what spring pressure you will be running....... 

Can you guess which "bushed" rocker this is 

No.... but I bet your going to tell us arent you!

Don


 

[nivvy]

not until you tell me how much open pressure the comp cams one can handle 

440 source one's are rated to 600lbs open pressure........ 

Indy Will tell you not to run there rockers with too much spring pressure.... atleast there honest...... 

For roller cams yous need to run higher spring pressures also cudaguy 

[moparmaniac59]

I was gonna say that looks like a Comp. rocker. I think I'll be right at 600 spring pressure, but I will have to ask Kurt (owner of Magnum Machine in Chesapeake VA) who is building my motor. I trust him and have basically given him the reigns. I just ask him what to get or what he needs. I know he said the springs that came with the Stealth heads will "have to go". I almost got the Harland setup, but I shyed away because of the needle rollers and went with the Hughes racing setup. I hope it works out OK. I was hoping you would chime in here. Thanks for the input. I hope my rocker doesn't split like that!! Kurt expects this 543 to make 600-650 HP!! Should be fun!!

                                            Matt B.

[nivvy]

opt for the cryo treating with the hughes rockers.... 

[nivvy]

FYI... spring pressure you need to know the spring rateof the springs also.... etc


open pressure = seat pressure + (lift X spring rate)

example:

Seat pressure 300lbs + (.600 lift cam X 500in lbs spring rate) ='s 300 + 300lbs seat pressure is 600lbs OPEN pressure... 

[71chally416]

The Jesel "800/800 rule": Anything with less than 800 lbs of open spring pressure or less than .800" of valve lift doesn't need needle nose rollers.

[bb71challenger]

C'mon Stroker, anyone can find random pics of broken roller rockers. So you are saying that in a percentage type situation that aluminum harland sharps will outlast the steel comp cams rockers? I dont buy it. I too have seen the huge gouged out shafts you get from needle bearing although I dont have pics handy. To be brutally honest I bet Crane ductile iron rockers would outlast both the comp cams and the harland sharps put together!

[nivvy]

opinons vary..... high HP cars stuff will break regardless for sure they ALL will..... but again how much pressure did you say the comps are good for

If your building a 600hP car and cant afford to maintain it then you should be building a 600hP car.. 


Not trying to argue here.....