I've been doing alot of research on cams lately. Among the dozens of threads I've sifted through, I've seen multitudes of sigs with each listing people's individual setups. After comparing/contrasting alot of these different setups, the way in which people arrive at each of their respective power levels seems to boil down to two basic approaches with regards to camshafts:

1. Run as big of a cam as it takes to get to my goal, regardless of the rest of my setup. "Go big or go home."

2. Build up everything around the cam, and/or run the smallest cam I can get away with.

One thing I can say, is that this isn't as cut and dried an issue as who has the most money. There seem to be just as many people on either side of the coin whether we're talking about bone stock engines, or fully machined/forged/ported setups. I've seen just as many guys with built 383's with stage ____ heads running Lingenfelter 211/219 or Crane 227'ish cams, as I've seen guys with bone stock engines running CC306 or GM 847'ish cams....and vice versa. It's an interesting dichotomy.

I've posted a poll to get a feel for the general consensus, and would like to open up the floor for discussion with this question: which philosophy do you subscribe to, and why?

 

I am conservative and like a sleeper approach as well as good driveability. My small LPE 211 cam w/ LPE heads and all the bolt-ons did just as well as a lot of big cam setups a few years ago and I was able to pass a sniffer once I would swap out for my dual cat y-pipe (LT headers). I felt I had the best of both worlds.
Now I'm going big cube, solid roller however the cam is still rather tiny compared, but it has been noted as a proven performer and allegedly has an idle like a LT4 hotcam so I'm awaiting to see for myself.
As most anyone who's done multiple combos will say... it's all in what you want as well as doing your homework and making sure you choose the right combination to fit your application.

 

You don't have the correct choice, which is in the middle.

Rich

 

Pick the cam that will get you the goal you want, and then PROPERLY support that cam by picking the correct gear, stall, etc.

I'm somewhere in the middle really.

My cam isn't big, but it's by no means small.

 

I agree with this, the support components is what determines the effectiveness of any cam. A 26x/27x .750/.750 solid roller in a stock block with manifolds and stock stall and 2.73's would be far slower than the same car with a LT4 hot cam gears and a stall.

As long as your general set-up compliments the cam you can go big or small or right in the middle.

 

Cam is part of a system. If all the parts work together = happiness. If they do not = To pick the right cam, you not only have to know cams, you have to know yourself. What is important to you? What are you willing to give up? Cams are an exercise in compromise - you don't get something without giving something up.

TINSTAAFL

Rich

 

Can you elaborate on the reason(s) why you would choose a camshaft any bigger than the smallest one necessary to achieve your goal(s)?

 

That's quite different from: "..run the smallest cam I can get away with."

Rich said it well.

As you both said, achieve your goals. If you do that, does "size" really matter? How about we just lie to others about how big we (or our cams) are..especially if they satisfy the needs?

I'm always surprised when folks talk about designing an engine around a cam. If you can figure out what valve timing and lift the ENGINE wants to provide you with the results YOU want, you can then make a cam to do that. Well, you do have to stay within the limits of your chosen parts and physics of what can be actually be done. Figuring out what the ENGINE wants is the tricky part.

I like your quote form Smokey: "One test is worth a thousand expert opinions." - Smokey Yunick

Perhaps a thousand accurate simulations is worth at least as much.

 

Really? How?

You just got really warm with this statement. I'll tell you what about later on. Suffice it to say, that despite appearances, this thread is not about me.

 

Get the best/biggest heads ya can afford and build the engine around them. The flow,RPM's,and CID will determine the cam.

 

I agree. Spend the money on your heads. You can make very good power with excellant heads and a smaller cam. With bad heads and a big cam you will not get the results you are looking for.

 

I would vote for this.

 

I can't help but chuckle at this idea of a middle size cam being "correct," because no matter which way you slice it (small, medium, large), you're going to compromise somewhere no matter what you run.

Where at and how much the individual is willing to compromise deems what is "correct."

 

this is a correct statement. to me, the middle acknowledges compromises on both sides of the equation while still getting the most out of set-up despite the compromises.

 

We are getting pretty metaphysical here! Kind of like the "Zen of the camshaft". You can't talk about the cam in isolation. As others have alluded to, you start with an idea of what you want - a goal. And you must have an awareness of limits - financial, time, physics. And you meld these together into a harmonious whole.

It's easier to work out a race cam than anything else because it's relatively easy to define the goal. In the case of drag racing, to get down the track as quickly as possible. Fuel economy, emissions, and that sort of thing are irrelevant. As long as you can drive through the pits, drivability is not important. But even with a simple goal, you immediately have to consider the system. What is the weight of the car, what tranny will you use, is it an 1/8 or a 1/4m car? What are the best heads you can afford? What fuel will you use? Carb or FI? Nitrous? A blower? And so on. Once these variables are defined, you can start to think about cam specs. In the end, the right choice is unlikely to be the biggest cam or the smallest one. It will be the right one.

Bret designed a cam for me a couple of years ago that was a masterful compromise. Useage was street and strip. The car has a blower and nitrous is used intermittently. The car has to run on 100 octane unleaded as cats and a full exhaust are used. That's a tough one!!! I bet he made lesss than minimum wage figuring that one out.

Rich