Dual exhaust vs. single pipe?

[Tristan Smith]

For the new ZX I am running dual exhaust with an x pipe. Believe it is 2.25 in diameter pipe. I found a complete exhaust cheap, with headers (I won't even speculate about how good the design is on the headers) so it is easy for now. Of course I plan on running the stock motor this year. I may change things up when I finally build a race motor.

[billf]

Chris,

I too have pondered this question. My original thoughts were to end the exhaust into a single pipe (3 in) open until it proves to be too loud.

If I could point out, the exhaust pulses of the V 6 are even on each bank, which is different from V 8's, therefore the equalizer pipe is probably not needed. If you merge to primarys into a common pipe, the equalizer (balance) pipe is created, anyway.

When I actually get the car project started, I will go this route for the simplicity of it.

I'll remain curious which option you choose.

Bill

[JeffYoung]

It's going to be a while before I even look at my ZX. I have a set of Stillen headers, not sure what they are worth, but would sell them to you for a fair price. If you aren't interested, understand.

Red, if I were you, I wouldn't spend big bucks on headers and exhaust until the motor is built. Then talk to Burns.

For the new ZX I am running dual exhaust with an x pipe. Believe it is 2.25 in diameter pipe. I found a complete exhaust cheap, with headers (I won't even speculate about how good the design is on the headers) so it is easy for now. Of course I plan on running the stock motor this year. I may change things up when I finally build a race motor.

[RedMisted]

Red, if I were you, I wouldn't spend big bucks on headers and exhaust until the motor is built.

Why is it critical to have the motor built first?

[planet6racing]

There is a great article in this month's Racecar Engineering regarding exhaust design. I'd recommend reading it, running through some of the calculations, and making a decision from there.

[JeffYoung]

A "built" IT motor will breathe differently than a stock one, and the exhaust should be built (in a perfect world) to account for that. Check out the spreadsheet on the Burns Stainless page and see some of the parameters they use to build a custom set of headers and exhaust -- some of those parameters can change with an IT build.

Why is it critical to have the motor built first?

[RedMisted]

A "built" IT motor will breathe differently than a stock one, and the exhaust should be built (in a perfect world) to account for that. Check out the spreadsheet on the Burns Stainless page and see some of the parameters they use to build a custom set of headers and exhaust -- some of those parameters can change with an IT build.

Jeff:
That sounds about right. But where I am now with money, I couldn't afford to do the IT engine build. In the meantime, I'd still like to modify my exhaust for any gains that can be realized.

[JeffYoung]

Understood. Then, what I would do is buy some off the shelf headers, and have an exhaust shop with some race experience build you a "rough" no cat straight exhaust, and run that for a few years until you build an all out IT motor.

[RedMisted]

Understood. Then, what I would do is buy some off the shelf headers, and have an exhaust shop with some race experience build you a "rough" no cat straight exhaust, and run that for a few years until you build an all out IT motor.

That's what I'm thinking. Just keep it simple until I can really go to work on the motor. Thanks for the help. I'll do my research for when that day comes.

[Tristan Smith]

It's going to be a while before I even look at my ZX. I have a set of Stillen headers, not sure what they are worth, but would sell them to you for a fair price. If you aren't interested, understand.

Thanks, but the ones I have seem to be a Stillen knock off. As a matter of fact, just about every aftermarket header I have seen looks the same. Like a Stillen knockoff. Maybe it's "THE" design, and maybe custom headers will need to be fabricated down the road. All problems for later. Hopefully the cage will be completed by next Saturday and the build can finally start to move forward.