Exhaust outlet modification

[NSX/MR2]

Does anyone in here have any idea how to make the air circulate better in the stock exhaust system, (to gain hp,) beside going with an after-market exhaust system? Do I gut the exhaust and go with straight pipe/down pipe? Do I need to play with the cat. converter or what? If so, how can this be done? Any special tool that i would need? Keep in mind that I intend to tackle this dilemma myself.

Thanks,
De

 

[Soichiro]

Home Made Headers and Exhaust

This is an EASY project! First go out and buy a mandrel bending maching, a heli-arc welder and a supply of stainless steel tubing in various diameters. Then make some headers and exhaust pipes. I would do this in a series of 1/4" increments in lengths and 1mm increments in diameter. Put one set on, do a series of performance and dyno tests and record all values. Now take that set off and put on a slightly longer or wider set. Repeat all the tests. Don't forget to test EACH header length against EACH exhaust length and EACH tubing width to find the optimum. I'm sure you can do this in under 6 months time and the tools should only be a few thousand dollars. Get ready to save at least $1.85 over an aftermarket design which provide proven horsepower and torque gains. Foohey on them, do it yourself!

 

[j14nsx]

Aren't you forgetting a CNC mill to cut out the flanges, and SS plate to make the flanges?

 

[ss_md]

As the above posts suggest you are not going to save money doing it yourself. Header building takes more than some pipe and bending tools. You are better off buying an aftermarket header and exhaust system, you will save alot of time, money and grief.
If are you trying to accomplish a specific exhaust tone then you could try to build an exhaust system after the cats. The best bet is to purchase mufflers from Flowmaster or other manufacturer, then have a shop install them. Just my $.02.

 

[maomaonsx]

home depot!

 

[NSX/MR2]

This definitely looks tough. Will have some thinking to do. What I want is better breating, and better sound altogether than just the typical upgrade. I got the Comptech exhaust before, and found it to be ok. I just thought, with some ingeniuity, this would work.

I thought that Mark Johnson has a down or straight pipe system for the NSX.