My 2002 for f150 with the 5.4 has developed a pretty bad crack in the passenger side exhaust manifold, and the ticking/tapping sound that it makes when going down the road at any speed is starting to drive me nuts!
So, I've been considering having a shop replace the stock manifolds with some type of header. The problem is, I've heard shorty headers don't really do much in terms of HP gains or sound over stock manifolds, is the true? I've heard longtubes are the way to go in terms of gains, but then the shop would have to run a completely new exhaust system. I've also heard that both types of headers love to blow out gaskets and often need the studs re-tighened, is this true?

I'd greatly appreciate any feedback/opinions this.

Thanks, Chopper

 

Any header will have to have the stud re=torqued at least 2 times after install

There are header gaskets available that are almost fool proof, and when torqued properly the first time will last

The shorty header manufacture depends on what one is better than the others.
Some shorty headers are equal tube, just like the long tube, just depends how much you want to spend.
No matter what header you put on, you will still be restricted if you don't put on a free flow cat system, and a free flow exhaust system.

 

and to add to what Charlie said, once you put on a free flow system to take advantage of the headers, you will then probably have to add a tuner to turn off the CEL that you will get due to the low back pressure high flow exhaust system.
my opinion is it is not worth the money spent for the minimal power gain.
you would be better just using stock manifolds.

 

Mod motors aren't like the overhead valve motors. they breath well, like the old hemi's

 

unless you put a k&n filter in the air box, then they starve for air after the pos filter plugs up with dust.

 

That's good to know that if I find the right gasket it will stay torqued after the first two times.
If I got shorty headers I would probably keep the exhaust that I have right now which is just stock exhaust without a muffler, at least for a while. Thanks guys.

 

IF you oil itright. If not the dust goes in the engine

 

I tried JBA shortys first. No real performance difference. Went to kooker long tubes. I replaced the flowmasters with a magniflow dual 2.5 in and .out with x pipe in it. Huge difference. Cut a few tenths of quarter times. Theyusually add about 30 hp to a 5.4

 

I gutted my cats on my F150. I used simulators to make the emissions show right to the ecu. No inspection where I lived. They don't test emissions here. My Dodge has a empty cat. I fixed it by using a adapter to move the rear O2 senser away from.the flow of the exhaust. I just scanned it. My emissions are right again. It was throwing a code before I fixed it