Bear with me, I can't make any posts short. What is eveyone's experience with Edelbrock Performer RPM heads for a big block Mopar? Back story: I bought a cheap motor home 440 for my '66 Coronet, a cheap set of redone 516 heads (still small valve) and I have a free/unused Comp cam CL21-228-4. I looked at the combo, still probably 8.5:1 with a big cam and figured it equaled a dog. So I went hunting for a rotating assembly, found a deal on some CP pistons with H-beam rods, zero gap rings, and Clevite rod bearings. Got them home and did some research, and they appear to be for a 4.15" stroke crank. So now the small valve, unported , closed chamber heads go from mildly inadequate to completely inadequate. So, after all that, I have narrowed my head options down to what is available, which is Edelbrocks, or port the iron heads and add big valves. The cost may be a wash. So what is your experience with Edelbrocks? The 84 cc should put me right at 11:1 with a 0.039 gasket. A little higher than I hoped, but livable. Obviously I'll have to get the short block together and do some measuring before I order, but I'd like some feedback on the Performer heads. Or the E-Street heads.
The combo: '66 Coronet 500, street/strip. 727, TCI 11" convertor, 3.54 Dana, Cal-Tracs, Assassin Bars, QA-1 Double adjustables. All steel except for a glass hood, full interior, working heater, etc.
Ran a set on one RB, no problems. Did need some cleanup & porting to get good flow #s (Edelbrock's were exaggerated), and I swapped to a double spring. Stealths on another, stronger RB; I like the OEM appearance, again worked fine, same mods. Folks seem to really like the TrickFlow 240s & 270s, reporting more power.
For anything that doesn't have to be restored/stock, I prefer aluminum heads by a mile: Lighter weight Better flow usually than OEM Easier to port, or repair if need be Less detonation sensitive More CR options depending on application
Ran a set on one RB, no problems. Did need some cleanup & porting to get good flow #s (Edelbrock's were exaggerated), and I swapped to a double spring. Stealths on another, stronger RB; I like the OEM appearance, again worked fine, same mods. Folks seem to really like the TrickFlow 240s & 270s, reporting more power.
For anything that doesn't have to be restored/stock, I prefer aluminum heads by a mile: Lighter weight Better flow usually than OEM Easier to port, or repair if need be Less detonation sensitive More CR options depending on application
My first choice was unported Steaths. Out of stock. Trick Flows are a little bit out of the budget right now, but I have them on my 512 in my Super Bee and like them a lot. I looked into Promaxx(out of stock) and Sidewinder(also seem to be out of stock). Maybe by the time I get the crank and the block bored, some will be in stock, but I'm kind of inclined to buy some things before they are not available, either. I've heard of quality slipping on the E-brocks, and the fact that they are the only thing still to be found is rather concerning. But I'll just have them checked over before they get bolted on.
there's pro's and con's to everything. when i did edelbrock rpms the castings and port window location wasn't great. the rocker geometry wasn't close so there was a push rod expense. i wanted to run factory valve covers and they wouldn't fit, another expense. pro's are spark plug selection and i do think they burn a little cleaner than factory iron. power wise i don't think they make any more power than a ported big valve iron head they replaced and definitely cost a little more to install in the long run. if all you have is '516's then you'll need to do something for heads. 11:1 with pump gas would make me edgy but you'll have to pick your poison.
I bought the RPM heads when they first came out. (don't really want to think how long ago that was!)
I've had quite a few years of good service from them and really can't complain for the $1050 per pair that I paid.
Car isn't very far off from what is being considered, but is 451ci. Really has been a fun combination.
Did not really do much of anything to the heads. I had them milled to 78cc, had the guides honed slightly looser, lapped the valves and had them backcut to the lap line, and I blended in the rough cut opening at the intake/exhaust flange.
More neutral to negative comments than I would have expected. Unless you were running Indy stuff, this was the premier head for over 10 years. Mild street engines? People were using them on a ton of stroker builds and went pretty quick. With unported stealths flowing in the 250's, typical competent ported heads in the 260-270's (real world) and these in the 270-280 range (I think the early ones were really pretty close to 290), I think they are a great choice of head. Until recently, you had to go to truly race type heads until the Trickflows came out.
Not giving anyone specifically a hard time and this is the "Race" section, but I feel these heads saved big block mopar street/bracket engines in the early 2000's as we really had nothing else other than 40 year old iron and horrible Stage VI castings..
There's some stuff in the tech archives about them that is pretty positive. Pretty good step forward when they first came out. Still on my 440 all these years later.
More neutral to negative comments than I would have expected. Unless you were running Indy stuff, this was the premier head for over 10 years. Mild street engines? People were using them on a ton of stroker builds and went pretty quick. With unported stealths flowing in the 250's, typical competent ported heads in the 260-270's (real world) and these in the 270-280 range (I think the early ones were really pretty close to 290), I think they are a great choice of head. Until recently, you had to go to truly race type heads until the Trickflows came out.
Not giving anyone specifically a hard time and this is the "Race" section, but I feel these heads saved big block mopar street/bracket engines in the early 2000's as we really had nothing else other than 40 year old iron and horrible Stage VI castings..
A lot of guys always want the new kid on the block. Edelbrock big block heads easily go 300 plus with minor work. 310-320 with some effort and probably push 330 with a valve change and a little more work. Put on a ported single plane intake and a big enough cam and you have more street, street strip power than most guys want or need.
Ede heads are still as effective as they ever were. What has changed is they’re several hundred dollars more that they once were....... and there is now a competing head(TF) that offers more performance for less cost than buying and modifying the Ede heads to reach equivalent flow numbers.
If I were looking to build a hot street/mild bracket engine, and TF240’s were unobtainable, and there were RPM’s on a shelf somewhere, and I felt I’d be ready for heads before the TF’s were available........ I’d just get the RPM’s and modify if/as necessary.
Re: Edelbrock Performer RPM Heads. - 01/05/2206:18 AM
I got one of the early sets way back when and they replaced my lightly ported 906 heads with big valves that flowed about 255-260cfm. There was an improvement for sure, but because of a camshaft change at the same time, I can't contribute it all to the heads. I had absolutely no issues with the heads at all, they worked well.
With a decent sized street/strip camshaft, flat top pistons, the E heads, 1 7/8" headers, single plane intake and a 750 carb it made 360rwhp (about 450hp) on the dyno-jet chassis dyno and ran high 11s at 115mph in a 3600lb B body with 3.91 gears.
Re: Edelbrock Performer RPM Heads. - 01/06/2210:44 AM
IMO, the E-Street heads are a good bang for the buck. If your not expecting to set the world on fire they are a nice upgrade from the factory cast iron head. I built a real mild motor with them, +.030 440, 9.2-1, MP .528 mechanical cam, 1-3/4" pickup headers. With an M-1 single plane and a 750 Edelbrock carb it made 455hp&508ftlbs, with a Weiand TunnelRam and 2- 750 Edelbrocks it made 469hp&542ftlbs.
