hey, i am in dier need for a pros opinion on a quality brand name for good underdrive pulleys, headers except for long tube headers that will give me pretty damn good power and sound, and if i should replace my spark plugs with carbon ones. this is for my 2002 mustang gt with borla cat-back, K&N cold air intake, and throttle body spacer.

 

Well UDP's won't help much with that.I'd say an X pipe and gears would be my next mod's if I were you.NGK make's some good plug's.

With the X pipe and gears your car will be louder and feel like you gained alot of HP.

 

IMO the Steeda pulleys are the best, but I didn't feel a power gain by adding them though I'm sure I gained something.

 

I'm not a pro but I do have Steeda UDP's and fit and finish are superb.Headers other than long tubes...I have Bassani mid-length and they sound good and according to a test in MM&FF a full Bassani exhaust gives about 17.4 RWHP.One more thing about pulleys,don't get piggybacks.You can get the non piggyback type from Steeda and March.