There has to be someone who has... straight piped their exhaust (just cut out the muffler and put a straight pipe in, left catalytic converter in tact) on their Ram w/ a 318!!! If you have done this, how did it affect your gas mileage?? Good, bad or no change? I have all the tools I need if I just go out and buy approx. 24" of, what probably 2.5", exhaust pipe (i need to measure it) to straight pipe my exhaust system in a very inexpensive way. I just don't want to do so and get worst gas mileage than 12.5. Even if I could improve my mileage by 1/2 mile I'd consider doing this mod.
Please let me know, your response will be valued!!! Thanx, David~

 

it is pointless to do this but if you want to it may lower mpg by .5mpg or so.