Has anyone or would anyone try it?

 

Not sure, check here.
https://www.northamericanmotoring.co...fications-189/

 

Yes, people have. Here is a friends in her blog...
http://lorigriff.in/phinnys-new-exhaust/

I want to figure out if it could be done pre-cat, but I highly doubt there is room up there as it would a nasty growl. I found a compromise and it was to cut out the 2nd cat and resonator, stock DP and mufflers.

 

I was thinking of just eliminating the res and 2nd cat and putting the cutout at least a foot before the muffler.

 

It doesn't make a huge difference. I have a R55 and thus it has 2 mufflers, but on anything else with the single muffler, it doesn't do too much. I have a buddy who hollowed his R56 muffler out and said the in-car noise was the same and any difference was negligible. I know when i put in my "test pipe" to remove the 2nd cat and resonator it made a difference, so here is a video with the pipe cut right after the flex pipe...just stock DP, no 2nd cat, no res, no mufflers, and no pipe. (click the picture for the video I think)

 

As far as performance is concerned it's not a gain or at least I don't think it is. It's like having the blow off valve adapter. All you want to hear is the woosh. I want to do it for the noise it makes. I already have a magna flow muffler welded in and no res. I did t eliminate the 2nd cat because I thought it would throw a light. Other then that I just want to be a nuisance I'm not going to lie to you guys. I live in a ricer area so it will be fun.

 

I only did it for noise and I knew there would be no power difference really. I saw a surprising increase in fuel economy, as much as 2mpg from the free flowing I guess, even after the restrictive stock cat? I was happy, not the reason I did it, or even expected result, but I am happy.

 

I had a straight piped subie impreza 2.5. car was slow as hell, but it was very loud. Also had a straight piped mustang and that was ridiculous. the cut out will give me options lol.