ok so i'm looking to find a cam for my truck.. the engine is a 90 318 which is still the la block.. oo its a rollor motor if that maters..

my questain is... my running a 650 holloy 4 barral street master intake, headers..

so whats the biggest cam i can run.. i really,really like the sound of this truck.. http://www.youtube.com/watch?v=nMtu6P1C1U8 Which hes running a 513lift 240 duration... somone help me i need a cam and really need to know what does what. what cam speics make that awesome sound.. can my 318 take it..

 

That's alot of cam for a big truck. The lift does not affect the idle lope like the duration does. For driveability I would not recommend more than 230 ish duration as that is moving the power band up alot. As far as lift goes, go as high as you can for your drivetrain/ piston heights. Lest we forget a new torque converter for automatic. That truck has pretty open exhaust too. In all fairness, the main question is: What are you building the truck to do? Having a .600 lift cam at 280 duration sounds cool, but drives like crap under 4000 rpm since the vacuum is nonexistant at that rpm. Are you building the engine to match the cam? If not, then you will not realize any meaningful gains. Wider LSA= flatter torque curve. Most aftermarket cams are ground around 108-112. The 108's have more peaks when dynoed as opposed to the wider lsa's being more smooth as they cover the spectrum. The smaller LSA does produce more torque and HP, but at a higher RPM. The roller cam is more expensive than older styles. Most have their cam reground if not an all out build.

EDIT: One of your questions were comparing a carburetor to the cam, which is not really comparable. The cam should be chosen based on a set of components used, like the intake and heads. If you run stock heads with a large cam, you will hurt your overall driveability, because the heads will not support the cam in the upper rpm range. The intake should also be chosen for the ideal RPM range. Hence a dominator intake (highrise style) is for 4000-8500 rpm, and a dual air gap style is for 1500-6500. The cam is chosen based on what you want, but you may need to change the cam based on what you have.

 

i personally wouldn't have that truck with that cam. as siggie said it pushes your power band up way high. in a truck you really need the torque at lower engine speeds unless you lighten the hell out of it and run it on the strip.
it wouldn't fun to drive offroad i wouldn't think because you just wouldn't have any low end power. you'd have such a high stall converter it'd be nuts. if you want a race truck then that would be cool. would be way fun.
i think of it this way. i had a 3.0 ford wich made power around 5grand. not so good for towing. was hard to pull out without heating up the clutch. i hated it for towing. empty that truck would fly like a bat out of hell though. i had an old 2.9 ford it was the opposite. no high end power at all. was like driving a wall head on into wind. towing and offroad was effortless though. i never had it in 4lo. ever.
as siggie said it depends what your gonna do with it when it's built.
like a stock intake makes great low end and no high rpm power (short runners on the iside for the magnums) and m1 moves that same power band up (longer runners)

 

yea i know that would be too big but sounded nice..

well my truck will be used for lawncare but yet i'll still a kid so i want to beat on it but want it to have some power and sound good doing so.

anyone know any ok cams without being a arm and a leg.

 

old la 318 just pick a cam that's meant for trucks and youll see a boost youll love provided you can handle the incread flow wich seems to me you can as long as your exhaust after the headers is able to.
you could port and polish the heads or just get some for it.
if it were me though i belive i'd pick up a magnum for it. maybe juice it before you install it. you already have everything besides the motor pcm and wire harness.
would be an easy install. that get you a very nice boost. my 96 is a bone stock mag 318 auto with 3.21 gears 4x4 crew cab and it's got plenty of power for me. towes great and all so maybe that would be a good option for you?
im partial to mpi and our mags though. you really can do quite a bit with what you've got now just remember to keep your power band lower for towing or you will regret it.

 

It is not necessarily the parts, but the accessory parts that add up all too quick. As far as cams go, you might look into changing the lifters instead of a cam swap. I would really really impress upon you looking into buying heads with a cam swap. They are very complimentary. You could clean up your original castings and buy thinner head gaskets, but with ultimate power comes the ultimate pricing. If this is going to be a work truck then I would NOT DO A THING to it. Keep it stock to minimize complications. I am sure you could buy a roller engine for the price of a camshaft and tear it down to modify it for a later project. Then as you gain real interest, you could buy used eddy's or a nice cam/intake moly rings, pistons ect. and then swap the entire thing when the time comes.