B-pipes? What's out there these days?
 

What are people running in their fits for best performance gains?

Looking at what's available on the market these days it's slim. Is Megan Racing the only company with a 2.25" B-pipe? A-spec and T1R (if you can find it) are 2". Anyone know of any companies making a 2.25" B-pipe?

Megan is what I have on my GD. I think I could only find it and T1R when making my purchasing decision two years ago. Really I think I just bought Megan because it was less expensive and I had the Megan downpipe too.

Spoon makes a 60mm one... Its made to order so there WILL be a wait if you order new. It was about a 4 month wait for mine.

Not sure about J's Racing but I believe they are least made a titanium mid-pipe at one point.

J's is only 2". The titanium is beautiful but that price tag hurts.

B Pipe
 

I hade to google the term 'B-Pipe' to understand this discussion. So 'B-Pipe' in this thread is referring to the section of piping after the catalytic converter and before the muffler? Or are you guys including the cat converter in this as well?

Someone else can correct me if my wording is wrong, but I think for purposes of this thread and in general the b-pipe is synonymous with the mid-pipe, or the pipe that connects the downpipe to the muffler just aft of the rear axle. The downpipe refers to the pipe between the b-pipe/mid-pipe and the header.

Both correct. The midpipe, the exhaust pipe that connects from the cat to muffler.

This is also for a GD3.

02 08 Jazz Fit JDM 2 25" Catback Exhaust System Stainless Steel Canister System | eBay Has anyone used the generic eBay exhaust downpipe and mid pipe with other available axleback exhaust? The one linked is 2.25" piping and from reading I know that most aftermarket B pipes like the T1R, Spoon & ASpec for the GD3 is 2". Has anyone tried the 2.25" piping above with say the Apex SV catback or OEM Honda HFP axleback?

There is NO HFP catback for the Fit just for the record. Its only an axle back muffler.

Typo on my part I meant axle back lol.

Are you asking if anyone has used an Ebay axle back muffler?

the megan pipe I have is 2.5" piping with a necked down ends 2" to fit any axle back.

J's is 50mm and is a nice lightweight piece of titanium though you can get it in 304 stainless steel as well.

Why necked down instead of 2" all the way through?

I've argued this concept with some guys in the past, saying that the exhaust should taper down slightly about a half inch or so, from the header all the way down to the muffler exhaust. I always thought this would be a good way to keep exhaust velocity up as long as it was not a restriction. I'm talking about starting a larger than stock then tapering down a half inch. Interested in knowing what your reasoning is for the piping diameter reduction (Just to fit any axle back?).

it's not the way I would have done it, that is how megan manufactured it. I actually cut off the piece they used to neck it down so my exhaust is a solid 2.5" from turbo back. I used their b pipe since i bought it for cheaper than I could fabricate it myself.

I'm asking if anyone has used an eBay full catback exhaust, but just the b-pipe section with another different axle back. A full catback is $120 or so shipped but I hate the N1 style axle backs they come with, I already have a T1R VIP axle back. I wanted to know if the b-pipe from the eBay catback would bolt to the T1r without any modifications.

I would imagine any b pipe would bolt up to other brand products.just be careful with the pipe sizing correctly fitting with no leaks.

B pipe
 

I'm actually in the market for a B pipe now. I HATE waiting for manufacturers to make something but am a little hesitant to go with a muffler shop's crushed bend piping. After constant reading, 2" pipe seems to be the magical number to shoot for in an N/A Fit. 2" from the 2nd cat converter to the muffler.

I currently am using a 2" muffler now. I may wait just a little longer before moving on this. Looking for minimal gains from this mod (1-3hp). This on top of an expected 2-4hp from the muffler change.

What other exhaust mods are you doing/have? I wouldn't hold your breath on companies making mid pipes for the GD3. Megan Racing is about the only company that continues to make a mid pipe and other exhaust parts. The pipings size though is 2.25" but tapers at the end to 2" (STUPID).

if you dislike the crushed bends that exhaust shops do then order madrel bent elbows online and bring it into the shop so that they can weld those in.

If you were closer to me I would help you out with a custom setup.

I only have a 2" piping at the muffler. The tapering down sounds like it makes sense to keep exhaust velocity up but better to keep it same diameter all the way through I always read.
Edit: Here's an example of what I was talking about when I said I read about exhaust tapering in different places.
Autospeed Article

"In this particular application, an exhaust was wanted that would be 2-inch off the turbo, running through at least a 2-inch cat converter (typically, the cat is the most restrictive part of a free-flowing system, so going larger than nominal pipe diameter is better), a 2-inch resonator and then a rear muffler which would be either 2 inch or a little smaller. (Why would smaller be OK? Almost all factory cars reduce their exhaust diameters as you travel towards the back of the car. Whether that’s because the cooling exhaust gases take up less volume – or some other theory – the bottom line is that the factory engineers don’t have a problem with this approach, and it doesn’t harm power. Some aftermarket turbo kit suppliers also do this.)"




EXCELLENT idea! Not sure why I didn't think of this before. Feel like an idiot now. Thanks! I'll work on this possibly Monday since I'm off work. Man, this is exciting. Lol! Was considering 2" all the way through but 2.25" may be the ticket. Thinking 2.25" is more for 175-225hp range though.