I just got the performer rpm roller cam for my car. The cam card says not to use dual valve springs but to use the edelbrock sure seat valve springs. Also it says the sure seat vavle springs are made to go onto to stock heads with no machining. Is this true? My motor only has 10,000 miles on it since it was rebuilt so the heads are fresh. I bought new comp cams roller lifters that im going to put in. Is there anything else i will need other than the usuall timing chain and gaskets? Also edelbrock sales a valve spring kit with the retainers and locks do i need to buy that or just the springs? If anyone has ran this cam they should have already went through all of this. Im new to the roller cams. Also if anyone has ran this roller cam what do u think about it?

 

I havn't used it but ive read that Edelbrock cams are not too good, their ramp rates suck from what i remember.

 

Those are the hydraulic flat tappet cams that everyone talks **** about not the roller cams. The flat tappet cams have been around a long time and edelbrock has not updated their design thats what people are complaing about. Roller motors have not been around for that long.

 

Ok whats the deal this cam is pretty much solely designed for our cars yet nobody knows anything about it. The cam only fits 87-92 and that is thirdgen territory.

 

The cam only fits those years because it is a factory roller design. There is a small step ground in the front face of the cam where it "locks" against the camshaft retaining plate.

Edelbrock cams are "old." Roller and flat tappet, both. Yes, the flat tappets have slow ramp rates. So do the roller cams. yes, they are more aggressive than the flat tappet brothers of theirs. They pale in comparison to a Comp Xtreme Energy grind.

Examine the cam you are looking at: It has 234/238° of duration @ .050" tappet lift. Sure, that in and amongst itself may seem like a lot. However, look at the advertised duration: 296/300°. That's a lot. In retrospect, the Comp Xtreme Energy 282hr has 230/236° of duration @ .050" tappet lift. Pretty close. Until you look at the advertised duration: 280/288°. What does this all mean? The Edelbrock cam takes 31° to get from .006" tappet lift (or wherever they start measuring) to .050" tappet lift for the intake side. On the flip side, the Xtreme Energy takes only 25°. May not seem like a lot on paper. Until you look at the nose of the lobe, where the power is made, where peak air flow is. Slow opening from advertised to .050" means the valve takes longer to get to peak lift, and stays there for a shorter amount of time. Vice versa, the quicker the ramp, the quicker the valve opens to peak flow area and stays there longer. And the longer the valve stays open at peak area, the more power.

Hell, the comp extreme energy flat tappet cams have quicker ramp rates, if that says anything.

If you want an opinion on the cam, here's mine: get a Comp and get more cam for about the same amount of money. Take that for what it's worth.

 

Hey i know your knowledgeable so whats the deal with the valve springs and what all do i need to do this?

 

Oh and the car has a comp cam in it and it sucks and its one of the exteme energy grinds. But mainly because it is too small its the XE262HR. As far as the RPM cam goes i got a good deal on it and my car is just a cruiser not a drag car so is long as it thumps and runs decent im happy.

 

Oh, sorry, didn't exactly read the part regarding the valve springs. My bad.

Under normal circumstances, I normally suggest running springs matched to the cam. However, due to the importance of the valve spring, I also generally suggest you only run something from a MAJOR cam manufacturer (Comp, Crower, Isky, Lunati, Crane).

All other issues aside, looking at the dimensions for the spring, they are only a single spring (probably have a damper coil). They look to fit the factory spring pocket as they are a 1.265" OD with a .880" inner diameter. The seat pressure looks a tad bit low for a roller. though with the intensity (or lack thereof) with the cam profile, it would probably work. Still, at that, not sure I would do it.

The other issue about the edelbrock cam, look at the lift. It has mid .500's on the lift. Unless you have the heads machined for more lift (mill the guide bosses), there is no way that lift will fit in the generalized .460-.480", which is the factory lift window. So, to run the cam, the heads have to be pulled and sent to the shop for the guide bosses to get milled. So, sure you may get the cam at a discounted rate, but in the end you will pay equal, or even more, than just getting the cam that fits - simply because you have to have the heads worked over. And in the instance that you do have the heads worked over, I would suggest cutting the valve seats out and running Comp 986 valve springs, which are a much more "trusted" spring, so to speak. A proven winner, at least moreso than the Edelbrock springs.

There is a cam swap how to in my sig. Read up, at least, if that is what you refering to when you asked "what all do i need to do this?"

 

The required springs for either of those cams are going to require either screw in studs or pinning the rocker studs. Otherwise, you run the risk of pulling out a stud from the high spring pressure. You don't want that.

 

Hey stekman did u see the latest superchevy they did a dyno test with the rpm cam and the 170cc E-tec heads and made 515HP on 91 octane. The E-tec heads made more power than the Brodix 180cc heads. Not to shaby for peanut heads and a weak cam.

 

Stekman's profile stats
Car: Disabled
Engine: Melted
Transmission: Locked

 

Read all my posts over again in this thread and tell me where I said not to get the Edelbrock cam. I gave you an opinion, nothing more.

Go ahead and build the combo. I will bet my valve train that you will not meat the same power output that they do.

Have a problem with my profile? If you knew the story behind my motor, you wouldn't be bringing it into the issue. With that, leave my engine out of this. Thank you.

 

ok, then why even ask for help? Magazines do not equal real world. chances are they werent 'off the shelf' parts'

 

I agree, Edelbrock cams suck. Wanna know why? They are the same cams GM used 40 years ago. They are carbon copies. Some were good.... 40 years ago. Some of the ones they copied, also sucked 40 years ago, and continue to suck today.

If you are looking for a cam, you are best off looking at the companies that do cams, not just copy bad designs used 40 years ago. Look at Comp, Crane, Lunati, Isky, etc... not Edelbrock.

(BTW - about the profile, yes, you obviously don't know the story behind it. I do)

 

My main reason for saying all this was the flat tappet version of the cam is crap everything says its crap. But the roller is a lot better it a very nice cam and people are not giving it a fair shake. My car has a comp cam in and i hate it. But i guess it comes down to preference. It is way to often that people jump on here and tell others to do this and do that and nothing matches. That is what happened to me i read what people said was good and i wasted a lot of money on **** that didnt work together. Now i am playing it smarter im building a dyno proven package no B.S about this works or that works. I know what power this stuff makes and i know where it makes the power. I highly recommend to anyone to build a combo package that has been proven. It is way to often that people build expensive piles of junk that dont last and dont make the power that they thought they would. Maybe i shouldnt have came out and attacked you like that since you were trying to help but im just tired up people misleading others.

 

sounds like you had your mind made up before you posted, why even ask for opinions on the cam then?

 

Oh and like i was saying the flat tappet is a old design that is crap. The roller cam has not been around for 40 years so STFU and come again. You people need to keep up to date on this stuff. The rpm probably runs like **** when u dont match it to a combo. Its made to work with the rest of the RPM stuff. The comp cam or any other cam for that matter was not specifically designed to work withe the RPM stuff. Im going for a package not mixing and matching thats where u run into problems.

 

This is where its a VERY good idea to talk with the cam manufacturers, with all the details of your engine and its intended use (and be honest... dont say "race" if it only sees the track once or twice a year, and the rest is just to work and back) and have them make a reccomendation. Beleive it or not, they will probably be able to give you a better recomendation for your given combo, than 99% of the people on this or any other message board.

 

With my motor im not looking to set any records if i break 400 horse on the motor after everything is done than i will be happy. I also understand that magazine will strecth stuff and make it look better but they do that to everything. But they still show u what works and dont work.