I have a stock 390 rebuild going with some minor performance upgrades.
I'm switching to a 4bbl, with the edelbrock performer, adding headers, and I would like a good idling mild cam upgrade. A little better than stock. I know Lunati is good. Is this a good choice:
* Advertised duration: 300 intake/300 exhaust
* Duration at .050 in. cam lift: 223 intake/223 exhaust
* Gross valve lift: .514 in. intake/.514 in. exhaust
* Lobe separation: 112 degrees
* RPM range: 1,500 to 5,000
Or.......should I get the Edelbrock to go with the performer, or the Crane energizer?
Thanks

 

I don't like any of those. First, that Lunati is extremely long duration for a mild street motor. With 300 degrees adv duration on both sides, you'll have a crummy low end, really rough idle, and little or no vacuum. I hope you're not running power brakes or AC. I really question that rpm range, as there's no way that cam will pull from 1500 rpm. I think it's odd that lift is so low, too. It's "area under the lift curve" that you want, and there are two ways to increase it -- duration and lift. Generally, you want less duration and more lift, and longer duration lowers cylinder pressures and robs torque. The reason roller cams perform better is that they permit more lift on shorter durations because the slope of the lobe can be steeper. The Lunati seems backwards -- long duration with only average lift.

Consensus around here is that the FE benefits a lot from a dual pattern cam. I'm using a Comp Cams 255DEH, which has 255 degrees adv on the intake side, and 265 on the exhaust, with gross lift of .469 and .495 and a LSA of 110. It has a listed rpm range of 1000-5500, which is where I'll be operating my engine. I ran several dozen cam specs in Desktop Dyno, and the 255DEH had the best torque curve (peak of 475 lb-ft at 2000 rpm) and was among the best in hp (305 @ 4000). Highest horsepower (327 @ 4500) was from the Crane 343801, which a number of guys here swear by, but it's a higher winding cam and torque was down significantly compared to most others.

I'd suggest you look at any of the dual pattern cams from Comp Cams (along with the 255DEH, they have the slightly more radical 265DEH and 275DEH), Crane (343801, for example), and Crower (292H and the "HDP" series).

 

Melling MTF-4 Specifications


Dur. @ .050: 204 Int / 214 Exh
Adv Dur.: 282 Int / 292 Exh
Cam Lift: .280 Int / .295 Exh
Gross Valve Lift: .484 Int / .510 Exh
Center Line: 107 Int / 117 Exh

I went with this cam and am glad I did. It is perfect, with a very nice idle, great vacuum for power brakes and helps to produce tons of power.

My set-up is a 105 block, 390 bored 060 over, 10.5 pistons, above cam, Edel Performer RPM intake, Edel 600 CFM carb, windage tray, Pertronix ignition, 2.5" dual exhaust with Hooker Max Flows.

 

FrankVA, I'm one of those true believers of the Crane 343801 cam. I used it with a set Rhoads lifters to stabilize the idle. Even so, it has a noticeably choppy idle @ 700 RPM. I'm very pleased with how this cam has worked for me. However, I thoroughly enjoy romping on the accelerator and spinning up to 6250 is a daily occurance. If the '801' is bigger than you need, how about a crane 343941, it has 272/284 advertized, with 216/228 @ 050, .533/.563 lift and 112 LDA. Plenty of lift, not too much duration. If I were choosing a 390 cam for someone slightly less nuts than me, the 343941 would very likely get my vote. DF

 

[updated:LAST EDITED ON 16-Apr-02 AT 02:45 PM (EST)]I'll throw my hat in the ring and vote for the Edelbrock performer cam. I had a Crane in previously and the Edelbrock is way better below 2000 RPM. I can smoke both tires with 3.50 gears, thats got to say something.
After re-reading your post, the energizer is what I had in it. I would avoid it for anything under 2500 RPM. If I had a manual tranny and could keep the RPMs up, it might have been worth keeping. The prices are all pretty close together on all these so that shouldn't be a factor either.
What I liked about the Edel. is that on the desktop dyno, it was already at a level torque at 2000 RPM, any other one was still rising, even though there may have been some with higher peak HP and torques.