2000GT4.6

I am just a huge anti fan of mac. Anything that arrives with bad build quailty, is the cheapest part out there, and has fitment issues just sucks IMO.

1BAD3V

I understand that, I just noticed alot of people with Mac and from alot of people I heard it was good quality. I think I just need a new seal for the manifolds, I believe the exhaust shop threw it away, and thats why it makes a nasty sound at lower rpms. But I just dont understand why in D it makes it when I go WOT, but when I'm in P, it sounds badass. Maybe its supposed to be high pitched with my setup, I'm gonna switch to SLP LM1's sometime, so I'll see if its the combo or the h-pipe.

JPGT_00

I had that same problem with Flowmasters, about 2000 rpm's it would give out a rattle/vibration sound. I guess one of the baffels muffler was messed up. I changed them out to magnaflows and the problem was hard, its hard to dignoise over the net without some sound though. I would get a video clip.

I agree with you when you say MAC is crap. MY buddy bought Mac headers, had a leak from day one.

Paul1212

I have only 43000 on my 99 GT and I just changed the plugs to NGK Iridium, but it even before it was still making that noise. I also claned the fuel injectors. So i guess ill just take out my impact wrench and try to tighten them all back up. Do you think It would sound at least half way better if i changed from the Mac cat back to a Magnaflow!?!?!?!?!