I've seen a build(s) where people add heads, intake 'n such; yet attain 400 horsepower using a stock cam. I just read another post where someone recommended using the stock camshaft on an engine build. Now, if one is able to get 370+ horsepower on a stock cam, why not just upgrade the cam (even if it's just a bit) and get more horsepower?? Am I missing something obvious? Streetability? Durability? Cam won't match heads mabe?

 

Anytime you hotrod an engine, particularly with a cam, you effect the life of the engine. If the cam is already well suited to the goal and just improvng the head/intake nets what you need, you've increased reliability and longevity.

In my opinion of course.

 

I have seen those sorts of articles too...pretty interesting
As far as I am aware, the stock cam is cheaper and the idle and normal driving is smoother and from lower revs (but remaining lower overall)

Adding a cam can add power, torque and up the rev range.

 

A cam really affects where an engine makes power in relation to the rest of the parts. Some people like the better idle and better compatibility with EFI of the stock cam, maybe they're not concerned all that much about where they're moving power around at. You can make good power with a stock 302 HO cam for instance, but you can more finely tune the engines power to what you want by getting a different cam.A cam can make the difference between an engine with good power, and an engine with good power that runs well

 

This is true. On a sidenote, I find it extremely amazing that smog legal heads + stock cam can net over 400 horsepower. Seems like the legal stuff is the best, blows my mind.

 

I think it's cuz too many people look at hp and not torque, and don't understand the relationship between them. A lot of the street legal stuff makes good hp cuz it makes good torque and is efficient.

 

Yea, for street applications, torque should be one's goal . . .

 

but you can get cams designed for off-roading, or 4x4 stuff which will have more grunt on the bottom than your stock cam..... so a different cam doesnt always mean upping the powerband

 

Ok, I'll be the N00B. What is the relationship between HP and torque?

 

HP = (torque)x(RPM)/5252

This is by definition and doesn't change. Most dynomometers measure torque and rpm then the horsepower is computed. Note HP = Troque at 5252 rpm. You will see this is true for every dyno sheet when the measurements go to at least 5300 rpm.

Of course this begs the question "If torque and horsepower are related by an equation, why say hp is for bragging and torque is for the street?" This is because engines build peak torque at lower rpm than peak hp. So for daily driving where the engine spends most of it's time between 2000 and 4000 rpm, youare not using your peak horseposer, but you are in the band for maximum torque.

For a relatively simple but good read, check out
http://vettenet.org/torquehp.html

Hope this helps.