[YORCHI]

I bought my Mach 1 used from a dealer, I recently put in the MAC pro chamber in, and while I was underneath I saw the mufflers said Flowmaster on them, I thought it was odd since the dealer said it was completely stock, oh well, just a gift for me I guess. The part number on them is 42443 which I later found out is the standard 40 series, which is great cause it's the series I wanted to get regardless. But the only bummer, they're 2.25 inch, and I wanted 2.5 inch. So now I have a few questions...
1) does that extra .25 inch really make a major difference, and where/how exactly
2) if it makes a big enough difference to warrant going with the 2.5 inch, can I cut the inlet/outlet and weld in 2.5 inch
3) if 2 is not possible, would a shop, or anyone (ebay*) be willing to purchase them or trade me for 2.5 inch...
Lots of thanks in advance...

 

[YORCHI]

bump...
someone help please*

 

[dollarbill]

If they are 2.25 inch (factory size) then someone just welded them on to the stock cat back. You will gain anything at all unless you buy the entire 2.5 inch cat back. I would leave it alone, because unless you plan on serious mods you will see no gains from the larger pipe.

 

[enorbit3]

i would swap it out for a whole new catback....flowmaster makes a American Thunder catback using the 40 series..... u also have all the options of Magnaflow, bassani, etc, etc

 

[BlueStreak03]

The only real difference you're gonna notice is a deeper exhaust note and of course different tips. The catback on the Mach is already mandrel bent I think so the flow improvement from a 2.25 to a 2.5 inch system is going to be minimal.

 

[YORCHI]

Well I'm gonna go with JBA Shorty Headers, I already have the Pro Chamber in there, so the only thing that won't be 2.5 inch will be the mufflers, and I do have big plans for it, I wanna end it all with the best icing for this cake, a Kenne Bell twin screw supercharger, but that won't be till a few years from now.

 

[enorbit3]

i was gonna suggest you get a set of long tube or mid length headers, but i remembered that you just got a prochamber and either LT or midlenghts would not allow you to use your prochamber....as far as shorty headers, JBA cat4ward are awesome headers but sure are pricey.....have u looked into the FRPP headers of BBK tuned length headers...might be a lil more cost effective....

 

[meatball]

Last couple of sets of FRPP shorties I saw were awful quality - I'd come up w/another solution