I have a 95 Dodge Ram 1500 (318 ci) with 5" of lift, 35"x12.50", and 4.56 gears in the axles. The engine has a cold air kit and trottle body spacer. I'm looking to upgrade the exhaust from the end of the stock exhaust manifolds to the tip of the tail pipes which include the muffler, cat, and piping. I'm wodering what cat/muffler I should purchase and the diameter of the piping I should install. Does anyone have any advice??? Are there any calculations I could run to figure out the diameter? Thanks in advance.

 

it depends on what configuration you want. single out side, true duals, fake duals etc..

On here, with your 5.2 it is usually recommended 2.5" for single, 2.25 for fake duals. Can't remember the last true dual thread but it is probably around 2". I found a calculator online when I did mine and found 2.5" to be a nice compromise. From what I have found, exhaust volicity is important. Too large of a pipe causes the exhaust gases to cool. When the gas cools, it expands and slow down which is not what you want. Smaller pipe is better for low end, larger pipe is better for top end. I'd say 2.5" is a good size for these trucks... exp since they came that size from factory from the collector back.

 

remove throttle body spacer i put one on and did nothing! then took it off and actaully notice some power back lol

 

+1 for pcfixerpro's advice.

And +1 for lastrights advice as well. If you want a detailed explanation why TB spacers are worthless on our trucks, click here.