Camshaft Basics

Edited= excerpt from Isky site....... http://www.iskycams.com/techtips.php

..........However, High Performance is another thing entirely. Change one factor, let's say in this case, the exhaust system (installing headers and larger pipes) and you have just negated in most cases, the need for that longer exhaust lobe. Now couple this change with a different intake system and camshaft and you have really scrambled the equation. But, wait just a moment. Why is it that so many people (racers & cam grinders alike) insist on running a cam with longer exhaust duration regardless of what equipment is employed? The answer is "habit". Most of them have been somewhat successful in doing it their way and will probably never change unless virtually forced by circumstances to do so..........

Example #2 (Drag Racing) At the drag strip it's a little different and I feel more honest. Here, racers have long enjoyed longer exhaust... duration ......(If I may add specifically for the purpose of "killing" low-end torque) .........

For choosing a cam you will need the following information.

Purpose of vehicle = driver, tow vehicle, steet cruiser, street-performance, street-strip, strip-street, strip only, full out drag car, circle track car, G-touring, full G-machine

Engine you are starting with, junkyard, fresh block, rebuilt block, and what you want to make (stroked, etc)
Power curve desired
Engine type and cubes
Engine stroke and bore
Connecting rod length and rod ratio
Type of cam desired, flat, roller, hydraulic, solid
Exact heads used, flow at .500, and valve diameters
Exact static compression
Quench information, chamber shape, fast burn? etc.
Piston configuration, flat, reverse, dish, etc.
minimum fuel octane desired
Intake manifold type, brand, style
Carburetor brand, type, and volume rating
Ignition distributor, advance curve type, or vacuum, both
any forced induction and specific type
nitrous oxide
exhaust system desired, loud, quiet, short race, headers only

vehicle type
actual vehicle running weight including people and full tank of fuel
proposed rear end gear ratio
slicks or special tires
transmission type desired
if stick shift, weight of flywheel, and type of clutch and friction material

financial ability to make it happen
Power costs money, how fast do you want to go?