I got my snake 6 months ago (03 Cobra) and it has long tube headers with 2.5" pipe bolted to it and goes into 2 stock converters, 2.5" from there to mac prochamber h-pipe, 2.5" back to 2 dual chamber flowmasters, then 3" pipe from the back of the mufflers to the tips.. Who would set up that I dunno but it sounds good and crisp no popping even when I rev up to 6grand and let off but its just a lil too quite for me.. I would like 3" all the way back. 3" from headers into 3" high flow converters into 3" x pipe up til the point of the 3" pipe thats already on there.. Any suggestions, comments, video or sound clips of yours with a similar 3" setup I just described, how did it affect boost and dyno #'s???? Thanx.

Tim

 

What mods do you have done? because you don't need 3" exhaust till you start making a good amount of power.

Here is a Cobra with the MAC 3" catback: http://www.youtube.com/watch?v=9wdCHPQCLDU


Another random 3" setup http://www.youtube.com/watch?v=gof39FATcZw

 

just over 500rwhp and tq at the moment I want it to sound better for the time being but plan on putting 67mm twin turbos on in the near future... It has mac long tube headers, 2.5" pipe into stock converters into mac prochamber h-pipe into dual flowmasters then 3" from flows back..

 

I would just take it to an exhaust shop. Fabbing up a 3" collector and mid-pipe shouldn't be too difficult. Not sure if 3" mid-pipe exist on the market.

 

I know DR.Gas sells a 3" X-pipe setup and I am pretty sure Mac has a matching 3" mid pipe out there somewhere too.

 

You don't even need 3" with TT. Stick to 2.5"

I work with a guy who owns an 89 Notch running an F1R on s 351 and only hase 2.5" with dumps. Leave it be. We don't need any MAC trucks on this forum.

 

At big block amounts of power, he needs the breathing capacity of larger pipes. 2.5" works perfectly for a N/A small block, not one that's pushing over 500 hp at the crank.

 

I disagree. I have never seen a Mustang with 3" exhaust ever. Like I said my buddy works for Procharger and has an F1R-powered Notch, with 2.5" exhaust. The Mach he had before, F3R with only 2.5" exhaust.

 

Most never run it because it isn't a mainstream size. However, when you push that much juice, you start to leave some on the table by running pipes that small. For example, most manufacturers recommend 3" above 400 hp for engines 250-300 ci. That's why also most mild big block cars run 3" pipes since 2.5" is restrictive for those power levels. The main problem w/ 3" pipes though is size, and on a IRS car, that means the pipes are closer to the ground.

 

3" pipes will help and I think they're a really good idea considering you're making 500hp. With turbos the headers will go away and you'll use shorties. Keep the shorties to a reasonable tubing size (1 5/8") and your turbos will spool faster. After the turbo you'll want to have plenty big pipes.