Re: No Muffler straight pipe ? or Muffler?
I know its not stated here , but the OP is from South Florida, where there are no emissions, no inspections to speak of, and the cops have real policework to do instead of picking on someone for running no muffler.
Having run no muffler at one point (in between exhaust setups on my WJ), I would not recommend it, as the downpipes are not balanced at all, leading to a very cluttered sound below 2k. You need some sort of muffler to cancel out some of that. Not to mention it is extremely loud. There is a valid reason why Chrysler uses 30" long mufflers on the 4.7.
I am not familiar with how the WK Y pipe is set up, but I would bet modifying that to be equal length (or close enough), re routing the single pipe in 3" to a straight through muffler would make the sound alot cleaner, meaner, and attain the gas mileage you seek.
Due to my workload, please do not PM me as I do not regularly check my PMs. Thank you :)