Cams - For computer .vs non-computer

Hi all,

I'm in the midst of a mild 350 build-up and am down to 2 cam choices, one is a Crane, the other is Comp. There are others on the list, but these are shortlisted.

here are the specs:

Crane (114142)

RPM: 2.2-5.2
ADV: 272/284
@50: 216/228
Lift: .454/.480
LSA: 112

Comp: (12-209-2)

RPM: 2.0-6.0
ADV: 275/277
@50: 216/229
Lift: .462/.482
LSA: 110

My target is about 300hp +/- 25 (probably minus!) and I'd like to get at least matching torque at the bottom/midrange.

The crappy (cracky!) heads I'm using are the 624s with 202/160 valves with some very mild cleanup/port matching. Pistons are KBs and good for about 9:1.

At this point I'm more about building the bottom-end up, so the top is more of a budget. I have the 670 Holley SA and a Weiand Stealth intake.

Bottom line question is, after all this.. ahaha. the Crane says it is for computer-assisted vehicles.. but I like the spec.

Q1) Is there something I am missing in the spec or the construction of the cam that I cannot use it for a non-computer setup?
Q2) Any other cam you might recommend for this mild build?

Regards and thanks,
Nigel

You might want to email Crane and/or Comp and give them the specs on your engine and any other relavent info. like your rear gears, tire size, vehicle weight, model, etc. I know Comp has an online form that you fill out and email them for their recommendation. I have a relatively mild 350 and they recommended the Magnum 270H (12-211-2) for me. Click on the link below and when the page opens up look on the left hand side and click on "CAM HELP ONLINE". This will open up the form you have to fill out.

http://www.compcams.com/information/whatsnew/

Thanks Nova71 .. will go there now to see what they have to say.

The cam you speak of is on my list also.. however it fell slightly short as it is one of the most aggressive of the bunch with dur Adv - @50 = 46/46.

I don't want to push the cracky heads I have to much, and the two cams I'm looking at are less aggressive at 56/56 and 56/48 respectively.

Cheers and thanks again,
Nigel

Computer-controlled cars rely on MAP, MAF, and several other sensors that are easily messed up with lumpy cams. The main difference between "computer" cams and regular cams is that they typically have a wider LSA and careful use of duration to make sure the vacuum signal is steady enough for the computer to operate the engine.

It doesn't matter as much with a carb; when the carb gets a vacuum pulse it pulls in some fuel, but the computer (and knock sensors if equipped) get very easily fooled with a cam that's too lumpy.

In your case it shouldn't matter since you're dealing with a traditional SBC, but in some cases the cam itself is different; like for instance the 350 LT1 cam is a bit different since there is no distributor drive gear and no fuel pump eccentric, but when dealing with traditional architecture like you will be using; no worries.

You might consider putting some money in some used performance heads. I know you said you're on a tight budget, but they'll make a lot more difference at this level than the cam. With either one of those cams you could pretty easily have 350 hp or more with some Vortec heads... and they're pretty cheap, too.

Thanks Curtis!

I had to rework some of my cam numbers also as the advertised durations are diff for Comp .vs. Crane cams.. the end ranings didn't change, however the Crane is a little more aggressive than originally thought when "equalled" to the Comp.

This time round I wanted to build up a solid bottom end... as heads are relatively easy to swap out (and cams actually as well).

It's going to be a fun journey and thanks again for your help.

The "journey" is up in cardomain for those who might want to visit.

Nigel

http://www.cardomain.com/ride/419184

Curtis is exactly on the money, your about to go through just what I have.
I have a 91 350 and found the computer very limiting, cams to start, though I went with the Edelbrock part #2102 version of the cam your looking at, same #'s. it was just cheaper since I lived about 3 blocks from the Edelbrock production plant.
you'll notice a difference, power curve is wider and the motor simple runs much better with the after market cam, BUT, even though the techs say it's ok for the puter controled 350's there is a bit of idle search problem with these cams, at least 4 other people I know who have the crane or others ground for the puters have the same prob, though none of us would go back to less cam since the problem is not that bad.
again, BUT! after 4 years of throwing parts on my truck I'm a little disapointed at the results a bit, I'd say because of the limitations of the computer.
A good cold air intake, headers w/high flow exhaust all the way back, cam and an all new MSD ignition, is where I stand and though better, it's not impressive, not like when I threw these things on my old 440, or any of the 6 camaros I have worked over.
I have a nice set of vortec's to install, BUT! whats the use since my 400 or so cfm Tbi wont deliver much to the rest of the high flow componants.
From experience on this I can say that either of the cams will make a difference the puter is just way too limiting.
I'am at point in my build where I'm trying to figure out how I can get around this problem on a budget, but after I figure that out I'll probably want a bit bigger cam.
I dont know what your spec's are but as for me? after the parts I installed I'm sure I'm no where near 300hp, maybe 250 or so if I'm lucky with a tail, a wind, a little disapointing.
what I've got is a 91 GMC 2500hd, 350 w/a 4L80e<--beefed, heads are the 65cc swirl combustion and a 4:10 rear, I have been told by GM tech's that 190 hp is what the truck spec's at stock, and as I said I don't believe I got to any more than 250hp even after the parts I have thrown at it, though I feel I gained some torque as well it peaks at a higher rpm and for a longer range than when stock, not as much at low rpm, not bad just different.
My overall long winded point is you may want to consider other upgrades you plan to make rather than just a cam that will work "with the computer".
because working in those paramiters is limited.
just passing on my experience's.

Thanks FuzzyPuppy!

this was a very old thread for me but welcomed none-the-less...

Engine is pretty much all together save for the ignition.... one thing I did not make clear on my initial post was that I am building a non-computer controlled engine, and stuffing it into a '97 Talon body.

Kind of a modern-made-classic -- to steal from that Taco Bell commercial with the whole class-made-modern thing. :p

Right now I'm busy designing the mounting frame under the hood, and rebuilding the Jag XJS rear-end to put the power down.

Cheers,
Nigel