Quote:
Originally Posted by CobraEd
No backpresure is good
.
|
Here's an exhaust teaser - & I will maintain that correct flowpath & exhaust pipe diameter IS critical, as well as using mufflers of some sort in an exhaust system. A good friend of mine is one of the supervisors for floor operations at the Chrysler Viper development plant on Featherstone in Auburn Hills, MI.
Several years ago, while experimenting with different exhausts for the Vipers, they decided to plumb & run a 3" straight-pipe system on a test mule Viper, and dyno it. Like, no mufflers = no backpressure = a good thing! Plus, maybe it would sound good on the V-10 to boot. They did their thing & then brought it up to operating temp., where they discovered the motor was running about 30 degrees hotter, plus it lost about 30 HP. They shut it down, let everything cool off, & then they installed Super Turbo mufflers & re-ran the test. Everything went back to normal. They concluded there was an "expansion chamber" needed in the exhaust system for optimum running conditions. Also, on any application, if you reduce backpressure too much or use too large of a system diameter, you will lose bottom-end & midrange performance - you'll FEEL it. You must pay attention to what power your motor is putting out, & relate that to an optimum exhaust system diameter. My advice is that you transition to a 3" muffler flowpath when you are up around 480 HP, IF you are looking for optimum performance. There is a quantum leap in exhaust flow cfm when going from 2.5" to 3" diameters.
-Eric