Hey all, just got a question. Has anyone heard anything about the Edelbrock Performer RPM roller cam? I am currently running their RPM hyd. flat tappet cam with the stock stamped rockers in my 402. I did some playing around with Desktop Dyno, and to swap in that cam, would give me about 50 more HP and 80 or so ft.lbs of torque more. Does that seem fairly realistic with swapping out my stamped rockers for a set of roller rockers as well. Here is my current cam profile: RPM Hyd. Flat tappet
240/246 .560"/.573" 112 LSA 19 valve overlap

New cam: RPM Roller
237/245 .625"/.639" 112 LSA 17 valve overlap

I know many ppl on this site hate Edelbrock cams, but playing devil's advocate for a sec, would this be a feasible swap given the virtual performance gains, or am I more than likely going to be disappointed in the results. It will be about $400 for the cam and rockers.

Anybody have any ideas at all, even just based on the profile and swapping to a roller valvetrain, regardless of cam manufacturer?

I have no experience with Edelbrock cams other than I know they're just repackaged cams from another mfg. sold at a higher price.
I think instead of going after a particular cam,it would be easier to figure out what you want performance wise,or what your ET goals are.
What's the rest of your combo? rear gears? If you've run the car before and have the timeslip,post that too.

Basically I'm running a 402 with SpeedPro forged pistons, stock closed chamber heads(96.4cc), RPM intake, RPM cam, Edel 750 carb, headers, Mallory HEI, and 3.31 POSI. I figured the roller would give more a little more performance without sacrificing current driveability plus should be fairly matched with the rest of my combo without having to change anything else aside from the cam and rockers. My goals are mid to high 12s...

You don't need a roller to run mid-high 12's with a 396
I think you'll need 3.73 gears too,no matter what cam you plan on using if your goals are mid/high 12's
Do you have a timeslip for your current combo?

In a 402, a hyd roller that size will be too long at the seat. I just installed the Comp NX279HR [279/294, 230/242, .537/.541 on 113LSA installed at 108ICL]in my '70 spec 402 motor. Car is crisp, but idles at about 950-1000 RPM to get any vacuum (13"). Drop it down to 800 and the vacuum drops right off. The seat durations on that cam are most likely a lot longer. You could run anything, but I would suspect, that roller in a 402 will be especially lazy on the bottum end. I already had the roller lifters and springs so I went with it.

Sure to get crtiqued on this but hyd rollers come in 2 categories, good torque cams for low compression / low rpm motors and cams that need a lot of static compression to work right. Motors in the middle , I think are harder to size. JMHO!

Chris, I don't have any timeslips yet, I built the motor two years ago, it has about 10K on it, I guess my whole thing is not wanting to sacrifice everyday driveability, hence 3.73 gears. I drive the car a good bit on the highway and the 3.31s seem to fit well for my needs, I guess I was just hoping for the best of two worlds, being able to keep the driveability on the highway/street, and have something to break into mid 12s with if I went to the track.

Did I mention this is a hyd. roller cam that I am considering not a solid roller cam, just to clear any misconceptions.

Ed,I kinda figured the RPM cam you mentioned was a hydraulic roller smile.gif
Obviously,there's more than just the cam to consider when it comes to an ET goal..its the entire combo that matters.With that in mind,and for what my opinion/experience is worth (not much)
I'd run the car as is,and see what you got.It will be much easier once you have a timeslip to gauge where you want to be,compared to what you have.
Running it first before changing anything..now that would be worth it.
BTW..
Very,very cool ride you got there..I like the sleeper big block mode graemlins/thumbsup.gif

i have heard that the eddie cams are from crane . how true this is i cannot say

Actually, that is pretty good advice Chris, I may be barking up the wrong tree. I should indeed establish a baseline and see what I have going with my current setup, before I invest the time and money to potentially be disappointed. Thanks for the good comments on the car, maybe we'll get to meet up at Musclepalooza 2.

nvr2fast, on paper it sounds like you have more motor then my 396 which is punched out to 414ci and you have more gear then my 2.73's for sure.......im running 107 mph in the 1/4 which would be good enough for 12's with proper gearing a just alittle more stall......then what i have now.......

im running a smaller 233/239 @ .050 cam,750 holley ,rpm intake headers,Full exhaust, in a 3900lbs car.

just in tunning alone i have achieved 5 mph thru the 1/4 and theres more left!......

so i would say tune on that bad boy and get it to the track......more then likely you have 50 or 60 hp waiting to be found thru the carb and timing and such.......just as i found thru my combo.....

looking thru your homepage ..nice car....i noticed you say your heads are stock......if you was interested in freeing up some more hp with min. cost.....remove the heads and do some porting...nothing major clean up all the runners of there casting and blend the bowl and rework the short turn radiaus...this alone with a simple hand drill and dremel tool will give you 3 or 4 mph in trap speeds which is about 30 or 40 hp gain......i have done some back to back testing on this on my own cars and see the gains myself with no other mods......its not rocket science ...just a matter of doing it.....you have the combo there just needs to be fine tune....you have a lot of power waiting to be released.....and 12's will be easy with your current motor.......

Thanks dd, I appreciate the compliments, I have considered doing some porting and polishing on my heads, however, I have heard from many that it would be a negligible improvement. If what you are saying holds water, it would most definitly be worth the cost of new gaskets and some time exercising my drill and dremel.

I will probably still use the car as it sits now as a baseline, and when the time comes to take her down the 1320', I will be able to determine what needs to be done. I feel that my goals are not far-fetched, and if it is a matter of tuning and making my heads flow more efficiently without compromising my current setup, I would definitly be content, especially if the mid 12s can be had.

Whoever told you that porting and polishing heads isnt worth it just doesnt know how to port heads. If you do a bad job, than yes, the gains arent worthwhile and you can sometimes hurt your performance depending on the kinda job you do. The cylinder heads are one of the biggest dictators of how much power an engine cam make. Think of the camshaft as the "brain" of the engine. The camshaft has a pre-determined of what it wants to do, how much power it wants to make, and how high it wants to spin(just like you yourself, or your brain has thoughts about what you would like to do). But, if the heads dont allow it to happen cause they cant move the air required, its not going to happen. I Want to leap tall buildings, but my legs dont seem to agree with me. A good port job in any scenario will show gains, sometimes more substantial than others depending on the app. In your case, you have a nicely built engine, yet stock heads. You are definitely in a position where a good port job can really wake that motor up. Might as well start by nailing down the tuneup for a baseline before you take the engine apart and do anything to it. But if you do choose to port the heads, here are some links to show you where to start.

http://www.replikamaschinen.com/auto_chevy.html

http://www.babcox.com/editorial/us/us110128.htm

Head porting obviously works when done right...according to my cars weight and timeslip I have at least 25 HP over the desktop dyno rating of my motor with a stock 882 head flow profile.

People say DD overrates power to start with so I'm assuming that means my gains could be more than the difference between the numbers?

All I know is that most people consider track results to be accurate at judging HP and I've got extra power from somewhere...