Exhaust Basics

[ebod]

I've searched/read a lot of exhaust-related posts. I still have some basic questions:

 

-- What are the differences between single-in/single-out, single-in/dual out and dual-in/dual out systems (I assume that the terms refer to from engine to muffler and to from muffler to exit)? Can you put any one of these types of systems on any engine or do some of them work only on V-8's or V-6's or I-6's, etc.? Does each type have different pros and cons?

 

-- What types of performance gains/losses do you get from the various types of exhausts? Do they just shift power from one part of the rev range to others (e.g., some help low-end torque at the expense of high-rev HP, etc.)? Do any increase power across the entire rev range?

 

-- Can you actually FEEL the difference an exhaust system makes in performance (I know it's hard to tell because the beefier sound makes it seem faster)?

 

Thanks for any "Exhaust 101"-type advice you can provide.

[Shaners]

If you are replacing just the muffler/tailpipes and the Stock muffler is Single in, then you will have to run a single in muffler (It can be either single or dual out, depending on whether you want dual exhaust tips). For example, my stock "can" on my HD 6.0L is dual/dual. I could run 2 single/single mufflers or replace it with one dual/dual. I suppose if I wanted it to look goofy I could run 2 single/dual mufflers and then I would have 4 exhaust tips coming oout from under my truck.

 

Most mufflers will give gains in the upper RPM's but a loss in low-end grunt. (Keep in mind that these Vortech engines need back-pressure to create low end power). The less restrictive or open the muffler is, the higher the power band tends to move...

 

I would tend to say that in these trucks, any HP gains of less than 10 HP would not be felt in the seat of your pants...

[MCourson]

I understand all the deal about needing back pressure but does anyone know how a little less back pressure effects the older TBIs?

[bigtruck21]

all engines need some backpressure for torque. Too little backpressure kills torque and means more free flowing which means more high end hp. Enough to too much backpressure means plenty of lowend torque but less hp. I've talked to plenty of people saying a single 3in system will make more tq and equal to more hp than duals. On high performance engines however, duals will allow more exhaust gases out to make more racing hp top end.