mufler bypass

It's very popular with 928 owners. Deepens the sound. I've heard a 355 challenge with, i think, straight pipes and that was super. Give it a shot.

 

If you're going to bypass them, make sure that you fabricate tubing to actually go to the tips - you don't want that heat inside.

--Dan

 

I ran my 348SS for a couple years with the cats in place and muffler removed and staight pipes out to bumper. It sounded great accept that there was a low pitched booming at about 2300-2500 rpm. From 3000 up it was great. My 355C has the straight factory exhaust this is very loud and it had the same problem low pitch sound as the 348 had. I got rid of most of most of that problem on the 355 by inserting header baffles in the upper and lower pipes after the O2 sensors.

 

Vern - can you describe the header baffles some more? I am having similar issues with a cross-pipe I replaced my center resonator with.

--Dan

 

Dan, If you have access to a Summit Racing catalog they are in the exhaust section. They slip into the exhaust pipe, they're kind of hard to discribe.the pictures they have will explain the way look they better than I can. There are two versions in their catalog I used the cylindrical type not the cone shaped version. regards, Vern

 

Hey John,
I was having a bass res. that was kind of tough on my ears, us old guys get picky about the noise that WE think is ok, LOL. I was also concerned about my neighbors who are mostly non tofosi. As you said too, I don't see that range much either usaully just in my neighborhood. I thought that the higher pitched note I achieved at lower rpm would be easier on thier ears too. My 355C is basically an open exhaust with baffles, wow the sound at above 4500 is something to appreciate, nothin' sounds like a Ferrari with volume turned up. On your PS, I have lived in Montana all my life nice way to live a quiet somewhat uncomplicated life.

 

Vern - thanks for the tip. I'll check into it for sure.

The problem with the 550 is that with all the torque D john), I spent a lot of time in the 2.5-3k range (plus 2800 is 80 in 6th). My thought was to change out the x-pipe design on the center pipe and instead put two separate tubes (one per bank) in its place. The cans are straight-through with some muffling / packaging around them, but I know how the cans sound w/o the x-pipe (great).

Perhaps what's needed is, as you state, baffles at the cats.

--Dan

 

Dan
you should look into the reason for X pipe. That concept is used sometimes to balance exhaust paulses. I don't know if that is the case on the 550 but I'm suspecting that there is a tuning issue here. Just a thought. regards, Vern