YORCHI

I have Flowmaster standard 40 mufflers (part number 42443) on my Mach 1 right now, but they are only 2.25 inch mufflers, I would really like to put 2.5 inch instead...can I just cut the inlet/outlet and weld in 2.5 inch pipe. How exactly does the extra .25 inches make difference wise as in sound/power. My last alternative would be to find someone that would buy them, or hope a muffler shop can either trade me, or give me a discount for taking those mufflers instead...thanks in advance

95stangergt

i am pretty sure you cannot cut inlet or outlet of the flowmasters or any mufflers.

MikeHawke

there are adapter pieces to fit almost any diameter of pipe to any other diameter of pipe.

There would be no power advantage for you to change the mufflers to 2.5" muffler unless you swap out the whole exhaust to a 2.5" system (atleast the midpipe and catback). The 2.5" system will help you wil making power because it would flow better. As it is, you may as well keep what you have unless you upgrade, at least, the whole cat back.

Nobody is likely going to give you any money for a couple of used, welded in 2.5" flowmasters. You might get lucky, but it's doubtful.