Whats a good exhaust for my 2003 F150 5speed 4.2L? There's a flow master on it right now, can't remember what series though. I got it for $45 at the local junk yard off another F150. Cut off after the cat, took it home and threw it in. I think the truck had a bigger motor than mine. Just trying to see if there's something better out there.

One more question. After putting on the exhaust that's on now, when I give it gas it kinda whistles. Kinda sounds like a turbo on a diesel. Just want to know if it's good or bad? Is it not getting enough air now? or what?

 

Magnaflow SI/DO is the best exhaust for a 4.2. You could get headers also but its not necessary!

 

Flowmaster 40 series is the least import sounding exhaust for those things.

 

magnaflow is the best overall exhaust for a 4.2. flowmaster gives it a deep idle tone, but when u get above 2500 rpm, it sounds like a ricer. like trimble said, get a SI/DO, it sounds the best, especially when u have it paired with a CAI(cold air intake). I have a few sound clips in my sig. they arent the best, but hope they will help.

Best of luck!

 

Thanks for the input you guys.