[kwon]

I was thinking about running an hks supper dragger on a n/a 73' 240z. I have a 6 into 1 header right now with 2 1/2 exhaust pipe that runs into a muffler at the end of the exhaust. But then I read some posts and it seems everybody is running there mufflers a couple feet behind the header to create back pressure/ horse power. What are the pros and cons of each set up. What kind of probblems will I run into.

 

[FlameZZZ]

1st you must realize that it wont make any noticable difference on a car that only makes about 165hp, do what u think sounds cool and dont bother about what other people say because most of them r only guessing.

 

[Roadman]

Hi kwon---------------FlameZZZ is right, you won't gain much hp with just the exhaust system mod on a stock Z. Having said this, I can tell you that the setup you have is probably better at high rpm ranges, especially with the 6 into 1 header. Adding a muffler or resonator near the header would tend to restrict the system and perhaps give you a little more torque at lower rpm's. To take full advantage of modified exhaust systems, you must also upgrade the carburetion and the cam.

Roadman

 

[winoman]

Ditto Flamez

Everybody has so many opinions about this and it is mostly just splitting hairs. Just do what you want and what you like the sound of.

steve 77

 

[Nigel]

back pressure myth

Back-pressure = horsepower, torque, whatever, is a myth. Back-pressure is bad period! A resonator just downstream of the header is usually to get rid of some resonace (sp?) issues, and has nothing to do with power.

Nigel

 

[szlash280z78]

Re: back pressure myth

i thought back pressure was bad, and that you want an exhaust system that has little to no back pressure

 

[toms78zxt]

Re: back pressure myth

Any dyno operator worth his salt will tell you it's not back pressure that makes torque in a n/a motor but the tunning effect of the pipe diameter and length and the distance of the muffler from the manifold outlet that determines the rpm range where power will be maximized. If it was as easy as creating backpressure to make torque you could just stuff a sock in the tailpipe and be done with it!

 

[szlash280z78]

Re: back pressure myth

hey tom, do you know what the best place for a 78 muffler is then?

 

[yo2001]

Re: back pressure myth

foot after the header. it supposed to be tuned for good torque and small back pressure

 

[Charles Freiss]

Re: back pressure myth

tom is the genuis on this question. How many funnycar or rails have resonator or mufflers. BACK PRESSURE IS BAD!!!!!! Next guy put the muffler where it belongs. chuck