What is the stock exhaust pipe diameter? Not the tip size, but the actual piping from the cats to the muffler. I thought it was 2 1/2", but just wanted to make sure. Thanks.

 

Ok, when you say from the cats, I'd have to include the Y-pipes. The Y-pipes are 55mm (little less than 2 1/4") that merges to 65mm. From the Y-pipe to muffler the sytem is 65mm (little more than 2 1/2") the crush bends narrow that down to 58mm at most bends in the system. Word to the wise, standard 2 1/2" pipe integrates into the oem system just fine, can't say I've ever seen 65mm piping of anykind to buy on the side.

Curious, what are you thinking about doing?

"All that's necessary for the forces of evil to win in the world is for enough good men to do nothing.”
Edmund Burke

G35 6mt

 

I am planning on putting in a Mccord power plate somewhere after the Y-pipe (but I might do duel power plates in the y-pipe). My friend has this on his Saleen S281 and the sound is ridiculous. I know you might lose some low end torque when the valve is open, but the gain on top-end horsepower is awesome. I saw several dynos showing 6-10 WHP gain from the open valve to the closed valve. Let me know what you think. Also, the entire thing is only going to cost about $250 installed with some simple DIY wiring.

www.http://www.mccordcg.com/mpp/mpp.htm