Join Date: Nov 2010
Location: Mostly Elmhurst, IL, sometimes Tomahawk, WI
If you go with any style aftermarket exhaust system, you will need to upgrade your ECM or you'll probably run too lean. This is because the new head pipes will flow better than the stock head pipes.
If you doing complete exhaust & ECM upgrade, then you should do a freer-flowing air cleaner air filter too so it allows better airflow on the intake side. Doing those three mods is what is commonly referred to as Stage 1. Dyno tuning is not really required, as there are many maps that will accommodate these enhancements...ask the manufacturer of the ECM upgrade for a map based on your chosen aftermarket components.
Stage 2 is when you open up the engine and add a hotter cam, maybe pushrods, etc. Stage 3 & 4 is when you do much more internal engine work(hi-comp pistons, head flow enhancements, etc). All these Stage levels are somewhat variable based on individual interpretation, but the Stage 1 components(complete exhaust, air cleaner and ECM upgrades) are very commonly done.
You can add just slip-on mufflers without doing the ECM/air cleaner upgrades as the stock head pipes will still be the most restrictive point. In this case, you will get a louder (maybe better sounding) exhaust note, but little to no increase HP or TQ.
2008 Black Pearl - Major upgrades are : 103" Stage 2 / PCV & AutoTone / V&H True Duals & Monster Ovals / Baker 7-speed Transmission
Arlen Ness 18" Rims & Avon Venoms / Brembo Differential Brakes / Hawg-Wired Stereo / Mustang Seat / Detach King TP / some other doo-dads
Last edited by SharkNose; 04-11-2012 at 08:01 PM.