97 F150, 4x4, 5.4, supercab....wanting to put headers and compatible/matching exhaust on my truck. looking at Gibson for both. Want to be able to use my spare tire space underneath, maintain towing ability (dont know why dual exhaust would hinder that but have read it might somehow). Want more power, better fuel efficiency...better sound, sure, but not so concerned with it. Need advice. Gibson, yes? can I use my spare tire space....also looking at a Fabtech or RCD 4-6 inch suspension lift...? Is there another brand/model I should be looking at and why? any advice greatly appreciated.

also, have seen CFM readings for different sizes of pipes.....what does it mean, what should I look for, what does it do performance wise?

 

From what I know and have learned, Gibson is good. Whether or not you can use a spare tire, well, if you go to the Gibson website, you can see what package is compatable with your truck. If there are any special circumstances or modifications in particular to your vehicle, they will add a referenced note next to the item, providing of course you are adding this to a stock vehicle. Good luck. I am in the market for a gibson exhaust myself. Happy hunting.

 

I looked at Gibson before I bought my Magnaflow kit, and it seems like all of the Gibson exhausts are designed to work around the stock equipment, meaning that you *should* be able to keep your spare tire right where it ought to be.

The CFM notes you saw are flow rates for various...things having to do with your exhaust. Basic rule of thumb is that higher flow is good, to a point. If you're pushing out more than you're sucking in, you should expect to see good high RPM power and comparably lower low RPM grunt out of your truck. If you tow a lot, it'd be worth considering, but my advice is to get what you think sounds best and what's proven to make good power and simply not worry about it, because just about any exhaust modification (to a point, I don't agree with pulling the cats off and throwing straight pipes in unless you've a turbocharger, and that's because I've seen the huge difference that can make; or running true duals because V engines really like exhaust scavenging that you can get with a good x pipe - that is when one exhaust pulse will help "pull" the next one down the pipe and out of the engine) will be an improvement over stock.