I want to keep my stock muffler just so I can moderately quiet most of the time. Im going to install an electric cutout so when I want the power, I can simply open it up. Im wondering if I should upgrade the stock (2.5"?) piping to 3" cat back piping with the cutout. So basically what size piping would yield more power with the cutout? Also can the stock muffer system be easily connected to the 3" piping?

 

That's not a bad question.

It's hard to determine at what power level you'll be outflowing a 2.5" cut-out...... I can offer you this info, though.

Derrick's car blows through the muffler now that he has the Ultraflow w/3" exhaust when he's on the jug w/cutout open
However, it's putting down about 625-650 crank hp

I'd say that if you are REALLY concerned about this, simply change the muffler in addition to the cut-out. A cut-out flows REALLY well and shouldn't start to back-up unless you are making SERIOUS power.

Mike

 

AFAIK, stock i-pipes are 2.75". Mine is still stock, and I'm running a 3" cutout.

 

I have a 3" cutout on my stock 2.75" pipe, I put it up in place of the cat.

 

IMO, if you're going to upgrade the intermediate pipe you might as well upgrade the muffler as well. But I'd doubt you'd gain enough horsepower to make it worth the money.