performer RPM package

[silversurfer74]

Hello all, any of you have experience with the Edelbrock Performer RPM package? (heads,cam and intake). I have a '74 L-82 and wanna wake it up. Look forward to hearin' from Y'all!

 

[tomtom72]

Hi, I have not used their packaged mods, but I called them first with my 'wake up my SB chevy' request. They told me that at the time they did not have a package for my usage ready for market. How about that for honesty! They also had suggestions for competitor's components that I might consider, along with advice for the one product of their's I was going to use(performer rpm intake manifold). With their help and advice I was able to put together a nice package of their intake, holley carb(my idea), and a Comp Cams cam(their suggestion to call Comp Cams). If I were doing it again I would go to Edlebrock just based on the way they dealt with me way back! tt72

 

[Glensgages]

tomtom72:

My buddy's hot-rod shop has dealt with Edelbrock repeatedly, and on several ocassions, they've advised using a competitor's part rather than their own (in certain instances)...

For this reason alone, I always try to use, or at least consult, with Edelbrock, when I'm pondering modifications.

 

[silversurfer74]

Any idea why the comp cam over the RPM?

 

[tomtom72]

Hi Silversurfer, My specific request to Edelbrock was about a 350 chevy marine engine. They did not have anything for my applicationat the time. The motor was based on the med. duty chevy truck motor, and I was not looking for high rpm power, rather more power in the 1500 - 5500 rpm range. Edelbrock said I should look for a cam with a split profile, mild lift increase with exh. lift greater than intake lift(to handle marine exh. restrictions); duration of about 280 or a little less, and fast opening exh lobes. In a marine motor without headers the intake side is not the problem, it's the exh side that hurts ya. They gave me a short course in cams, and said if I waited about 6 mos. they might have something for me. You know I would have waited, but winter is when you work on your boat so you can enjoy it all summer. No surprise, I followed their general teachings and got a perf.RPM intake with a holley 4550/650cfm and a Comp cams 268Hi Energy cam kit(pushrods,springs, rets.,locks,guideplates,screwstuds,roller tip rockers1.52 ratio,timing chain set,lifters). Stock flat tops,1.90/1.58 stock(pocket ported)heads and S/S head gaskets=9.3 c.r. about. All that added 20 mph to top speed at about 5500rpm, with the right prop ofcourse, oh yea stock exh. sys.,very restrictive. 4000 lb 23' boat, imagine what a matched system can do for a car? Oh yea, single I/O, not twins.

 

[Bob Chadwick]

silversurfer74,

I'ms sure you are aware of this but the Performer RPM intake can be difficult to fit under a stock hood due to height constraints.

 

[silversurfer74]

Good point!

I went ahead and bought the RPM heads, and cam. But only a (Power-Plus polished Chinese copy of the) Performer (not the RPM) intake for clearance reasons. Edelbrock guys say I'll sacrifice about 10HP on the top and pick up 10-15 LB FT on the bottom. Sounds less like a compromise and more like bonus! I haven't done any work yet due to the fact that we (Wife & Son) are moving to Florida soon. Don't feel like tearing down and running into time consuming setbacks. Reason for the move? Officially a job transfer. Let it be known that transfer was applied for based heavily on Minnesota's sports car season Vs. Florida's. See Ya, Silversurfer74

 

[curtis]

right about the RPM intake. the performer fit mine, but was real tight to hood with air cleaner on. Love my comp cam. 262H Extreme Energy. Vortec heads. a real torque monster at over 400 lb/ft horsepower not that far behind. Just don't put a giant carburetor on it. 750 cfm is plenty or you lose all your throttle response around town. I am dumb about the L-82.......is that a 350 or what?

 

[silversurfer74]

Ah yes, the L-82...Yeah it's a 350. It was the replacement for the AWESOME LT1. Not as brutish and powerful as the LT1 (which had a solid lifter cam and very high compression), but the mid 70's were a time of meteocrity as far as horsepower and fashion are concerened. Differences (upgrades) between the standard 350 and the L-82 were as follows: L-82 had;

impact extruded pistons (forged?), more aggressive cam profile (still an emissions regulated abomination), forged crank, higher compression (9.0:1) heads w/ 2.02/1.60 valves, and *****in' finned aluminium rocker covers.
Feel free to chip in and add anything I forgot.
I do like the L-82, it was a good engine considering the constraints it was dealt and the amount of performance it delivered...BUT, a guy always want's a little more.
See Ya, Silversurfer74

 

[MoeJr]

The L82 cam was the same cam they used in the 350/350HP engines of 1969.

 

[silversurfer74]

That, I did not know. Would the Edelbrock RPM cam actually be an upgrade then?

 

[MoeJr]

Yes the performer RPM cam would be an upgrade.


L82 Cam specs:224/224 Duration at .050 and 450/460 Lift.

Performer RPM Cam Specs: 234/244 Duration at .050 and 488/510 lift.

The RPM cam is pretty healthy in a 350 and you'll need at least 10:1CR to get the power out of it. If your car is an automatic you will need a stall converter of about 2500-2800 rpm to make the car feel snappy off the line. One of the reasons an L82 sometimes feels weak off the mark is because with only 9:1 CR the factory cam is soft under 2500 rpm. I would think your engine would produce peak hp around 5800 RPM with the Perf. RPM cam. I hope this helps.

 

[silversurfer74]

You bet it does. My combustion chamber volume is 64cc so compression will be requisitely high. Coupled to the M21 4, should have no problem getting the RPM's I'll need (except maybe for a few burned clutches). Thanks for the info.

 

[silversurfer74]

Is anyone currently running the same set-up? Haven't put mine together yet and want to hear the good bad and ugly first-hand.

 

[Jack]

With a new intake in the cards ... I might've considered Edelbrock E-Tec "vortec" heads ($60-$120 more than rpm) ... Summit K1107 cam&lifter kit (same grind as rpm but about $105 less) ... a polished Power-Plus 52006 "Vortec Cyclone" intake (about $10 more than P-P 52000). About same overall buck$, but with improved vortec-like combustion chamber design.
JACK:gap

 

[zgator]

For what its worth,I have a 71 Z/28 that came with a 79 L82 Vette engine and I went with the Vortec heads and Edlebrock intake from Scoggin Dickey and it was like a whole different engine and that was with no cam swap.A great deal!!

 

[Scooter76]

Which head is better Iron Vortec's or peformer rpm? I currently have vortec's on my car right now, but also have a set of new peformer rpms . I like the vortecs but I am itching to try the rpms just to see what they will do. From what I have seen the vortecs flow a little better on the intake side & worse on the exhaust side than the RPM's do. Any opinions?
thanks

 

[curtis]

Scooter, check out this info from Super chevy Magazine. Might help to answer some of your questions.

http://www.chevyhiperformance.com/techarticles/41598/index4.html

I also run the vortecs with comp cam 262 extreme energy. very streetable, great torque. My engine is like the Dangermouse engine you may have read about. In my opinion, the higher price of the aluminum heads and the small gain in power is not a good deal. You can gain quite a bit of Horsepower by getting rid of the factory windmill and using a good shroud and electric fan at a lot less cost than the upgrade to aluminum heads. I'm cheap!!!! and broke..

 

[Scooter76]

Curtis

I am running basicly the same setup as you, except with less cam. Crane 266
210/210 .469/.469 (1.6rockers) Overall I like the power of the vortecs. Mine have been upgraded with screw in studs & dual springs good to .550. Peformer vortec manifold & a Jet stage 2 Qjet. It runs really nice. I also have the dual spal fans. I have a set of new in the box Peformer rpms & a regular peformer manifold that I aquired some time back. I was wondering if it would be worth the trouble to try them out or to save them for a nother project. Thanks.

 

[Flared69]

I have an original 69 L46 engine (350/350). Replaced manifold (Performer RPM), carb (holley 650, but soon to either be a holley street avenger 770 or a edelbrock 750), and cam (Compcams 12-224-4 - the second cam listed here: http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=219801&prmenbr=361)

Past two days I've been replacing the heads on her. Just waiting on a spring tool and some replacement pushrods to arrive (new heads are on nicely, about 1hrs work to go). With the intake & cam, on the old 750 I used to have, I was pushing about 400ish hp). With these new heads i'd like a bit more.

Oh and they're shiny too