For those not familiar with headers and the benefits they provide:

Headers are one of the easiest bolt-on accessories you can use to improve an engines performance. The goal of headers is to make it easier for the engine to push exhaust gases out of the cylinders.

During the exhaust stroke, a good way for an engine to lose power is through something called back pressure. The exhaust valve opens at the beginning of the exhaust stroke, and then the piston pushes the exhaust gases out of the cylinder. If there is any amount of resistance that the piston has to push against to force the exhaust gases out, power is wasted.

In a normal engine, once the exhaust gases exit the cylinder they end up in the exhaust manifold. It is here that exhaust gases from one cylinder build up pressure in the manifold that affects the next cylinder that uses the manifold.

Headers contain an indiviual pipe for each cylinder which come together in a larger pipe called the collector. The individual pipes are cut and bent so that each one is the same length as the others. By making them the same length, it guarantees that each cylinder's exhaust gases arrive in the collector spaced out equally so there is no back pressure generated by the cylinders sharing the collector. The longer these pipes are, the more efficient the "scavenging" effect of exhaust gasses takes place, thus more HP is generated...

 

Pacesetter LT's all the way

 

I don't have the pacesetters yet but thats what I'm goning to put on.

 

Pacesetter LT's for me but with a twist. Custom ceramic coating from a local shop...

 

will these perfectly replace the old exhaust manifold and will it pass smog?

 

I have a set of BBK's on the way, they are a short header and directly replace the factory log. I got them because I have 4x4 and really don't have the money to make alot of power but wanted some better performance and fuel mileage. Oh yeah and price for em ya can't beat it at $299 shipped got em at Moe's.

Johnnyk

 

^^^1^^^

I ordered the JBA shorties, because I couldnt afford the long tubes and just wanted to help her breath a little better. They will be assisted by 2 12" magna flow mufflers.

 

i have a 03 4.7 and the exhaust as stock goes like this....manifold to two resinators, one resinator has a sensor in back and front of it (o2) then they combine into one cat...is it worth putting headers on this truck and is there neway i can go true duals without messing up the comp?

 

How much do the Pacesetters run?...how hard is the install?...how hard is the install for some JBAs? Thanks all

 

If the 03 4.7L exhaust setup is anything like the 05 4.7's then those two "resonators" right behind the manifolds are catalytic converters and the converter you were talking about was the muffler.

The converters on the 05 4.7 are right behind the cats on the y-pipe and then the two down pipes are ran into a collector and into the muffler then on out the tailpipes.

Not tryin to be a smart *** or anything that just confused me because i thought that all the 02-05's has the same exhaust setup.