Discussion Starter · #1 ·
Im looking to get a new Muffler instead of a full exhaust and i need to know the inlet and outlet on my new 2011 GMC Sierra SLE ext Cab?
up...I'm also in the market for just a muffler. Just tuning in to this thread and doing some research. I'm wanting nothing too loud...just a nice mellow deep sound. 2008 Silverado 5.3.
That is what I am having installed tomorrow, can't hardly wait!:big_banana_Dance:I have a Magnaflow part#12259 and it is very low rumble at an idle after warm up and great sound soon as you get on it and doesnt drone you out when cruising i have always ran flowmasters before and can honestly say i will not go back after this it is also 3" in/out on a 5.3
Backpressure is a myth, it's all about exhaust velocity efficiency and a single 3" exhaust is pretty much optimal for a stock engine. If anything, that Flowmaster is reducing flow thanks to their inefficient chambered design, which also creates a lot of drone.I have an 01 gmc sierra rcsb stepside with the 5.3 that i just put a flowmaster american thunder catback kit on. I heard a 3" in/out reduces your mpgs so i went with 3"in/ 2.5" dual out both dumping out the passenger side before the rear tire and it looks/ sounds badass! I got exactly the sound i was going for but may be too loud for some. I went with the 40 series muffler, 70 series i believe would be a little tamer. If I were to do it over again i think i would have done 3" in/ 2.25" dual out for a little bit more back pressure. Mpg didnt change after i started staying off the throttle to listen to the sound!
I am going to have a 3 " in/ 3" out Magnaflow installed and leave my exhaust pipes the same. I guess I will find out soon, I am getting 15.8 mpg right now.I disagree sir! But you go ahead and put on a 3" and have fun with your 14 mpgs!
Lol, yeah okay...I disagree sir! But you go ahead and put on a 3" and have fun with your 14 mpgs!