I have an exhaust leak I have been trying to fix forever.

It is the passenger side where the y-pipe meets the manifold.

I am thinking the manifold is no longer round where the y-pip seals it.

If I am going to replace it, I might as well upgrade.

Anyone have any input on the Stainless JBA shorty headers

2004 4.0 5 speed

 

RonD will probably chime in a little later with a more detailed analysis. But basically headers are not an "upgrade", they don't increase power they just move the powerband to a different RPM range.

However, you will definitely be upgrading the finish on you headers. I think some stainless JBA headers would look good under the hood, and from what I have seen most people have been very happy with the JBA headers. Most reviews say they are not worth the money, but if you already have to replace them then IMO you should get the JBA headers.

 

Thanks for the input. JBA was stating a 16hp increase at the same 4872 RPM

As for looks... This truck is used and abused, not polished and pushed so I could care less

 

I haven't researched this stuff for a long time, but I am pretty sure that the 16 hp number you are quoting is JBA's claim when you add their headers, exhaust and ignition wires. Theoretically if you are gaining 16 hp at 4872 RPM, then you are losing hp elsewhere. Just keep in mind there is no way you will gain 16 hp throughout the powerband.

IMO they ARE an upgrade over stock and I would get them if I was in your situation. Just trying to make sure you understand the facts.

 

Think about that for a second.. 4872 RPM.. when are you ever at that RPM range unless maybe WOT?

 

Yeah, you're ******* the hell out of it at 4872 RPM

 

Some reading for you guys
http://www.jbaheaders.com/assets/dyno/04rangerdyno.jpg

 

Like I said, those numbers are for headers, exhaust and ignition wires. Still, you can see you are losing low end power. How many times are you at 4872? The JBA dyno clearly shows that stock has more power at 2200 rpm. Guess what rpm you usually cruise at at 65 mph? Ford isn't dumb, they tune their engines/exhaust to get the most fuel efficient numbers at the EPA mandated mph.

Also, keep in mind that was a study published by JBA, not a third party.

 

And that is why I asked. The chart shows at 2400+ the headers surpass the stock setup.


I already have a full stainless exhaust since mine rotted off 2 years ago and I was also looking at wires since mine now have 185k on them

 

Got it. Well yeah you should get them, the 4.0 loves those higher RPMs