Im going to get my H/Cat/E and I keep hearing these terms come up.

1. What's a bottleneck and how does it restrict flow? Where is it? How can I remove it?
2. Where is the A-pipe ?
3. Where is the B-pipe?

Thanks in advance.

 

no one? Please answer these!

 

I'll try to answer this:
1- You have a bottleneck when your exhaust suddenly gets narrower at a spot. There are about 4 bottlenecks in a stock ITR exhaust (not looking at header and cat). First, the flange near the cat. Second, near the flange to the axle back. Third, where the tube goes into the muffler. And fourth, the muffler tip (inner tube). The exhaust is 57 mm OD except at these four spots. I think the most important bottleneck is the first one near the cat. You can remove this by sawing it off and putting a 57mm or 60mm or 2.5" flange on it. If it's bigger than 57 mm, it should taper done to 57mm.

2- A-pipe is the second piece of the header. It's also called the secondaries.

3- B-pipe is the piece from cat to axle back (muffler).

 

I'd say that about sums it up

 

Thanks.