Chevy and GMC Duramax Diesel Forum - View Single Post

**ob_1jr** · 05-09-2007, 10:52 AM

I don't know about increasing MPG, but cutting out the muffler and installing a piece of straight pipe lowers EGTs some and is pretty cheap even if you take it to a shop and have them weld it in....or you could replace that stock muffler with a high flow muffler if you prefer. You can also open up the airbox to increase airflow on the stock box. Go to kennedydiesel.com and look under tech tips and airbox mods. That is free and it only takes a little bit of your time to do.

05-09-2007, 10:52 AM	eBay Motors #2 (permalink)
ob_1jr Super Moderator Join Date: Aug 2005 Location: Alaska Posts: 1,818	I don't know about increasing MPG, but cutting out the muffler and installing a piece of straight pipe lowers EGTs some and is pretty cheap even if you take it to a shop and have them weld it in....or you could replace that stock muffler with a high flow muffler if you prefer. You can also open up the airbox to increase airflow on the stock box. Go to kennedydiesel.com and look under tech tips and airbox mods. That is free and it only takes a little bit of your time to do. __________________ 2004 GMC 2500HD D/A CC Carbon Metallic w/ LB7 4" turbo back MBRP exhaust TST Powermax Programmer, Diablosport Predator 285/75-16 BFG T/A KOs, Eagle Alloys Series 187 Clifford 2 way remote start, High Idle, Bilsteins Extang Classic Platinum Tonneau Cover AFE Magnum Force Stage 2 Proguard 7 intake Kennedy Diesel Merchant Automotive My Photos