the JBP header is a failure. if you study any exhaust velocity what-so-ever you would know that bends take energy to get the exhaust to flow in a new direction. another failure of this header is its "boxer" sound. they claim its an equal length long tube. well guess what, an equal length header will not have a boxer sound. that sound comes from unequal length pipes. another failure of it is you want your exhaust to be as short as possible to the tail of the car to keep velocity up. the JBP adds length to the exhaust. this goes against everything ever proved in exhaust theory. why would it magically work on these cars? lets see some before/after dyno graphs if you are so sure it works

 

Yup the subie sound is a tell tale trademark of an UNEQUAL LENGTH HEADER...

Even Subies loose 90% of that sound when they switch to equal length runners!

 

Is that the spaghetti header? Equal length is the way to go.

 

FYI... I'm a piping designer by trade.... this is what I do for a living... deal with piping systems.
Please re-write entire post as to not put foot in mouth.

I've flow tested and power tested the header. It gains as much power as a Pacesetter or ZZP.... however it gains far more torque in the midrange as compared to most other headers.
It is nearly equal length, except on runner is about 1/4 shorter than the rest. (Note that I measured this twice.... first time around I came up with different results as posted on RLF, second time around I verified 'near' equal length)
The subaru sound IS NOT from the unequal length of the one primary... it is due to the header not having a rotational collector; two high velocity pulses followed by a short pause, followed by two high velocity pulses.

Further more, there is more to the exhaust than simply 'flow' or having a short exhaust.
Primary velocity in the tube is the key goal here, hence why it makes so much more torque than any other long tube header I've seen.
This has been verified by four other JBP owners I know... three local to me. The header is not a failure... it's the people that believe retarded internet talk that are the failure.


BTW... google 'equal length header'.
And, be sure to email every exhaust manufacture and tell them that 'spaghetti-like' equal length headers don't work.

 

i respect your answer but i really just don't see it working. how would primary velocity be kept high with so many bends that thing has? not to mention they are even more than 180* bends in it

 

In most piping systems, as long as you are mandrel bending with a radius above a certain factor of piping diameter, the wall friction is said to be 'near' the same as a straight pipe.
With that said, the larger the pipe, the larger bend radius. With headers, because you are dealing with smaller diameter pipe, the bends can be tighter without creating bend turbulence, or flow reversion.

Simply put; proper mandrel bends in a header do not hinder exhaust dynamics.

 

lmao all i did was post to figure out a way to get this pretty header in my 2.4, didn't want to start an arguement lmao.

but bottom line, to get it into the 2.4, I have to make one of the exhaust flange holes bigger? either side? and won't doing that cause an exhaust leak?

and how much bigger do I make the hole? it seemed as though I was off by barely a hair, it drove me crazy!

 

Did you try removing the intermediate shaft, and installing it from the bottom?

It might help if you had a friend here with a camera, taking a picture of where your interference is.

 

Slightly bigger making the hole more oval, by using a drill or round file. I placed the exhaust flange onto the bolts, and noticed that one side was not lining up correctly (like you noticed). You would thibk you shouldn't have to do this in the first place but it was the only way it I could think of without trying to put the allen bolts in that it came with. Besides didn't want to mess with the bolts in the head too much, and there's better clamping force with the original design.

 

I have picture, it is not a very clear image. and I followed the instructions and got the header in from the TOP of the engine, and that was ******* difficult!.

notice, im right above the bolt but it is not fitting, i can only get 1 side in, cant get both :S

 

my flange fit with no issuses

the key to installing this is you go from the bottom, collector first, get it up into the cavity, then rotate it around and get it right side up. After that it's just a matter of getting all the bolts tight. You want to leave at least 3 studs in the head to hold the gasket and align the new header.

 

^^ is it necessary to remove the stock studs from the head and replace them with the allen key ones? When I got my header, I didn't get the allen key studs

 

i only used 2 of the allen bolts. i used stock studs/nuts for the rest.

 

kay so then it is not necessary to use the allen bolts. But what difference would it make if I went from the bottom, I got the header in the back of the engine

 

it deosn't i didn't see your post, just don't have to remove the valve cover and stuff that way.

 

well next time I try to install I will go from the bottom. I just wasn't expecting to drill and make the hole in the flange bigger. And in my opinion, that would just cause an exhaust leak :S

 

Bottom is a fair amount easier. I had a hell of time getting it in my auto. And once installed it caused a coolant leak from the crossover pipe. But that only seemed to be an issue on autos cars as it was on a 5spd car before and after mine and neither owner seems to have a problem with it on that end.

 

won't cause exhaust leak if you're making that hole slightly bigger...just don't go crazy. just make it wide enough that it clears which should be miniscule amount. and you should replace your gasket if you're worried about it causing a leak.