Performer RPM Cam and Manifold.... Good riddance!
I'm convinced that the Performer RPM cam is too much for street use. I'm gonna lift out the engine again, and replace the cam to something more "streetable".... while I'm at it, I'm also gonna lose that Performer RPM manifold to replace it with something that will fit under the darn hood!... Hind sight 20/20.
Does anyone know the camshaft specs for a stock 350 / 350hp? Also, does anyone have recommendations for a "close-to-stock" cam that will work with my 64cc Performer RPM heads (#60899)?
1969 Corvette Convertible (build date December 14, 1968),
L-36 427, 390 hp (3963512 block; 3964290 heads), Muncie M-21, Monza Red, Black Top & Black Interior. VB&P Gymkhana 550 lbs/inch coil springs, Bilstein Sport shocks. In progress... full body-off restoration.
1972 Camaro Z-28, Rally Sport, Cranberry Red/Black Stripes.
LS-6 454/425, Muncie M-21, 9.8:1 CR, Lunati 60204 Voodoo Cam (Dur 276/284, Lift .554/.572), Holley 3310-3 (750 CFM), Weiand 8019 Stealth Intake, 3.73:1 Rear, Flowtech Headers 1.75" Primaries, Chambered Tube Exhaust, Custom Works GT Coil Springs, Hotchkis Sport Shocks.
Gone but not forgotten
you can get a "stock replacement" cam for the 350HP Hydraulic from Speed Pro which is a division of Sealed Power they should be availabe from most speed shops.
Question what rear end gears are you running? that is a major consideration in cam choice.
The 350/350hp (L-46) cam is reproduced by Federal-Mogul/Speed-Pro as their #KC-1095R (kit with cam and lifters); 224/224 duration @ .050", .450"/.460" lift, 114*LSA, takes their #VS-739R springs. Nice street cam.
fine69, it's hard to recommended a cam with so little information. We know you have compression chamber volume of 64cc. Also needed would be...
Compression Chamber Volume - 64cc
Head gasket thickness -
Deck height -
Piston valve pockets -
All the above numbers will equal compression ratio -
The above needs to be known to order the proper cam, but I'd think you want something with alot of duration to avoid detonation. And as stated your rear gear ratio if not stock. You can call Comp Cam at 1-800-cam-help and see what they might recommend also. Not that I'm a Comp Cam fan, I just remember their number
I'm sure the members here at CAC can help if you can supply the missing information.
Thanks Bossvette. I believe the rear gears are the stock ones.
Originally Posted by bossvette
I think you'll be happier w/ less cam ... I almost said just that a while back:
Originally Posted by fine69
Originally Posted by Jack
1095R is also same cam as in L82. I think it wise to step down from the RPM cam ... but I think the L46/L82 cam is a bit small for your 64cc/4spd ... suggest another choice is Federal-Mogul/Speed-Pro KC-1062R (kit w/cam & lifters)
Originally Posted by JohnZ
valve lift .468"/.480"
duration @ 0.050" 220°/231°
1062R also takes their VS739R springs but the edelbrock springs should do well.
Speed-Pro tech line 1-800-325-8886 ... ask for Jim ... he's not in India ... he's right here in USA, he's been w/ the company for a long time and he's been pretty darn helpful ... he's also a real car guy ... not just a csr.
I binned the Performer RPM cam in my 81, as I have said previously it pulled like a train all the way up to the rev limiter but was a dog under 3000rpm and in town it was terrible to drive. I was riding around in second gear just to keep the rpm up in the sweet spot, needless to say this was not only noisey but expensive as it guzzled petrol like you wouldn't believe around town. I opted for a CompCams XE270 which if I remember correctly was advertised as a tourqey 4x4 cam with slightly less lift but still a decent RPM range, much smoother idle and decent tourqe at lower rpm and worked well with the rest of the Performer RPM kit.
I'm really confused here! I am going with a 383 stroker with 5.7" rods, 16cc dished pistons which should net 10-1 compression w/ performer rpm 64cc heads according to the block builder. It will be running through a 700R-4 into 3.08 rears. It will also have a tuned port injection system. The builder quoted me cam specs with just slightly less lift and duration as the ones Jack gave for the performer rpm cam and said it would be great for a street car. Then I read this thread and am starting to have doubts! I don't plan on racing the car, I just like the sound of a fairly radical idle. I'm not concerned about vacuum cause if there isn't enough, there is always an electric vacuum pump. I don't know enough to have an educated opinion so here I am again asking for help. Thanks, Art
I forgot to add that a 2000 stall speed converter was recommended.
Gone but not forgotten
well you had better be concerned about Vacuum if you are going to use a TPI. The majority of conversion TPI systems are speed density which depend on a MAP sensor (reads manifold vacuum)as one of its main triggers. If you have a constant vacuum from an electric pump it will play hell with a computer. Make sure you get a computer friendly cam.
Originally Posted by Art Jett
FYI I ran a Engle 274H with numbers of 234 duration .480 lift in my 383 when it was carbed; it ran like gangbusters from just under 3000 on out with a 2400 rpm stall converter. when I put the 383 in the 76 with a TPI I used an Isky computer friendly cam with slightly more lift but with about 217 duration it pulls from off Idle and is much more smooth then the Engle was.
Originally Posted by JohnZ
Thanks, Jack. Yes sir, you were most certainly correct about this beast of a cam... and I made the wrong decision with the setup.
Originally Posted by Jack
How do you think the Speed-Pro KC-1062R will do for street driving -- with respect to torquw and drivable RPMs?
I called the Speed-Pro tech line, but Jim was not available. The tech was somewhat helpful.
Originally Posted by JHL
It sounds like I'm re-living your past experience, particularly the driving in 2nd gear to keep the RPMs while driving through town. Also, it's just so noisy and obnoxious.
I was not able to locate the specs for the CompCams XE270.
I am hoping that I will be able to replace the cam without having to remove the whole engine/tranny again.
Call the guys at Lunati and tell them what you want to accomplish. 662 892-1500
This is the one I used.
Com Cams Xtreme 4x4 X4270H Part # 12-243-3
Described as Strong mid range and throttle response, likes headers, gears, 2200rpm + stall.
RPM Range 1800 - 6000
I think I'd better go with even a little bit milder cam than that cause you are running a 4-speed w/3.70 and I have an auto w/3.08. I don't want to have to rev it like a race car to pull away from a stoplight!
Thanks for the input.
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