Andriy242

So my buddy had a Magnaflow 2.5" Xpipe and I grabbed it for dirt cheap and didn't realize the difference.

Now the w204 c300 if I am right is 2.25"?

Would there be a problem or anything bad if I get the guys to instal the 2.5" on a 2.25" pipe? Ofcourse they will do all of the necessary modification.

What do you guys think?

shotgun_banjo

I think someone did that and not had a problem. Ask a muffler shop to see what their take on it.

jbt56

With the larger pipe diameter you will lose a small amount of torque as compared to the correctly-sized pipe, but otherwise it'll just cost a bit more to install, as the shop will need to adapt it. It certainly shouldn't cause any 'problems'.

black lavender

You're not going to lose any torque on a small piece like an X-pipe. You'll be fine and it will fit. Any exhaust shop will make it fit.

Andriy242

SICKKKK~ Sounds good!. My other questions is should I removed the faux cats after the xpipe (between the muflers and the xpipe)?
I heard it sounds great, but last thing I want is to loose low end torque if I remove those as well.

jbt56

After spending most of the last 15 years in the performance exhaust industry, I can assure you that there will be a slight torque loss when using oversized piping in an otherwise stock car's exhaust. Will it kill the car? Heck, no, but it will be there. The bigger the pipe, the worse the issue. Same with removing cats and mufflers entirely. Too free-flowing of an exhaust does you no good anywhere but a drag strip- and there, only if the car/computer is tuned for it.
On the opposite side, a restricted exhaust will reduce top-end power by not allowing the exhaust to flow efficiently at higher RPM. It's simple physics.

Rodpwnz

Even though I wanted 2.25, my muffler guy insisted on 2.5 because he would be able to slide it over very snug and weld it onto the stock 2.25 pipes. I honestly wanted the 2.25 so it would stay uniform, but he assured me that it made no difference if it was .25 inches bigger. I didn't want to argue with a professional when I myself had very little knowledge in the subject. It sounds great and I'm not really sure of any torque loss.

Here is a sound clip of my xpipe:

C300Sport

Conversely, one could argue that opening the exhaust up 1/4 inch inside the x-pipe will cause turbulence that will then have to "squeeze" back down 1/4 inch to exit the x-pipe...you may be introducing more back pressure than you had to begin with...which could result in higher low RPM torque and lower high RPM HP.
Doubt anyone could say for sure unless you tested the flow over the full RPM range. Either way, the effect would be nominal.