GT Tim said:
I am finally putting the exhaust on my GT. I have read a lot of threads about this and I was wondering 2 or 2 1/4? Muffler and resonators? Side pipes where can you get them and how well do they work? I have a 32/36, pacesetter header, and intake manifold hogged out. Also I believe I have performance cam. This is the last 'to do' before I can paint. Any help would kick a$$. Thanks Tim
Usually for a mostly stock engine it is best to use 2" exhaust pipe to a non-baffled non-louvered perforated muffler of that size with a 2.5" over axel pipe.
I guess side pipes work but it is suggested that only one is to be functional and the other for show becuase it would flow too freely.
As Jordan said, you still have just a slightly modified engine here, driven primarily on the street. The goal is not "ultimate HP" production, but rather a nice broad band of usable torque. The idea here is to keep the exhaust velocity high to enhance torque.
2" pipe back from your header adapter and following the original exhaust pipe routing is your best bet to achieve this. For a front muffler, I would instead recommend a short 2" in/out "turbo" style muffler and then just continue with 2" pipe over the axle to either a twin pipe resonator or just straight out to twin tips.
JCW sells a really nice, 13" bodied "Turbo" muffler for about $20 with various in/out pipe sizes. I've used this setup on several of my GTs and it works! You can probably source something similar from your local muffler shop, though maybe not as cheaply.
Side pipes complicate routing and mounting tremendously and deter performance somewhat because of the circuitous pipe routing necessary. Unless you just absolutely "must have" them, I would recommend against it.