[Cobra Jet 351]

Well, I am swaying at getting the MAC Catback TK9635 system for my 2004 GT Convertible. Has anyone had any issues with a MAC System?? Any input would be appreciated!

 

[SoCal2V]

I'm not sure which one that is, but if it is their 3" system I wouldn't get it; 3" is too large and you will have a very noticeable loss of torque (as measured on the butt dyno) thoughout most of the rpm range. As long as it's a 2.5" system then go for it.

 

[Bullitt5339]

I'm not sure which one that is, but if it is their 3" system I wouldn't get it; 3" is too large and you will have a very noticeable loss of torque (as measured on the butt dyno) thoughout most of the rpm range. As long as it's a 2.5" system then go for it.

I have to disagree with this. With the stock manifolds and a midpipe on the car, there's plenty of backpressure so that you don't lose any torque.

I run MAC Pro Dumps and they fit perfectly, and with even with no tailpipes, I lost absolutely no torque at all.