I recently bought a 2000 GMC sierra 5.3 litre. I wanted to put an aftermarket exhaust on it. I was thinking about the 40 series delta flow FlowMaster with a 3in. inlet and dual 2.25in outlets. Is this a good choice? Will I gain any torque from it?
I ran two 40 series on my 350 Z28 and they were great; great sound. I now have two on the same car but it now has a BB 468 in it and 3" inlet and outlet. I think the sound may be too loud (not for me but for "others.") I'll know better when it gets out on the road. If it's too much I may switch to 50 series to avoid accumulating tickets.
Dare to be different. Flowmasters are actually on the lower side of the list for best flowing mufflers. I'd be looking at dynomax, borla, and a few others as well. Around here EVERYONE and their mothers have a flowmaster system. To be honest . . . I DO! And I cant wait to change it.
Dont get me wrong I think they sound great . . . but they do not sound unique.
I had a 5.3 with an ultraflow dynomax. It sounded really good, but the interior resonance at cruise speed was brutal. I really did not lie it. On my new truck with 5.3 I went with the 3 inch stainless Delta 50 series flowmaster. It sounds almost the same except that the cruise resonance is gone. I highly recommend the 50 delta series for a daily driver.