Originally Posted by 65smallblock
Fair enough. Have you ever seen someone place a set of headders or aftermarket intake on an otherwise stock motor and and actually get worse performance? I have, many times. A lot of times it comes down to killing back pressure or booster signal. Especially the latter. Some aftermarket intakes work well on a stock motor but probably about half of them are simply a bad match because they are designed for WAY higher flow capacities than the average street rod will ever see. Even more often Ive seen guys spend their cash on a complete aftermarket exhaust to see very little or no gain when they could have had a really good set of heads for about the same $ and realized some huge gains. Of corse your mileage WILL vary, which is part of the reason I say this. I think a lot of suggestions are generalized and assume that the poster is building a balls to the wall beast, and therin lies the problem.
I'll agree that some intakes are way overkill, most single planes fall into this catagory.
I just shake my head and sigh everytime I hear someone on the "not enough backpressure" bandwagon. Any backpressure is a bad thing, the reason they loose power isn't because of a loss of backpressure but because they have excessive ex. duration and it shows when you have a free flowing exhaust- when its choked down you need a little extra duration. The power loss isn't a result of a "lack of backpressure" but excessive ex duration- present on most stock cams and even a LOT of aftermarket ones. Stepping from a stock intake to a very mild dual plane is almost never a bad idea though. sure things like heads and a cam help too, but when it's about $1000 for a set of heads or $50 for a used intake... well you see the choice most people willt take. I do it all at once on my engines- pull it out and do heads, cam, intake, headers,pistons, the works- but for someone just wanting to go bit by bit the intake and exhaust are usually the best first step, then the cam, and finally the heads. (heads and cam together is the best bet, but most people do ehads last because of the price).
You can use a crap intake and get worse results- but the same is true for any part- it just takes a little bit of brainwork to make sure is all matched.