i got stuff for my 99 from diesel dawgs and stuff for my 05 from mighty diesel. both vendors on the site and both had awesome customer service i would highly recommend them any vendor on the site would be a great starting place

 

Factory exhaust might be 4" but its not mandrel bent and has lots of kinks. A good full 4" or 5" turbo back exhaust is a great place to start.



Luke

 

And how much HP does he stand to gain?

 

He will gain a few HP but the biggest difference will be exhaust gas temps will be lower.

Luke

 

Actually, unless it's a 04.5 Cummins "600", the exhaust is only 3.75", has a lot of unnecessary bends and the huge stock mufflers suck ***. Like Luke said, there's not a lot of power to be gained by going to a 4-5" exhaust with just a programmer/module but he'll see a significant reduction in Exhaust Gas Temps, especially when towing. Same with an intake. Plus, he'd already be set up should he decide to upgrade to more aggressive fueling in the future.

 

You are correct, from the turbo to the muffler is 3.75 but after that keg sized muffler it 4 inch. weird huh? and i would like to go for more power but its time to take baby steps for now. the rest will come

 

Smarty!