Exhaust question

[Nyjd516]

Would a flow master super 44 with 2.5 inch exit piping sound good on a v6 3.3l frontier? Would 2.5 inch piping from the cats back to the muffler make a sound difference?

[jerryp58]

"Good" is relative in this case. Right after I bougtht my '04 4-cyl I replaced the factory muffler with a Flowmaster so that it was easier to hear when I should shift (couldn't hear much of anything witht he factory exhaust). I also liked the sound, but like I say, that's a personal thing. There's probably some posts here with sound clips, but you ought to search on Youtube. You'll probably find a clip with a very similar setup there.

[Nyjd516]

Well what about performance, would 2.5inch piping from the cats all the way back to muffler and exit pipe be good or is it too big of pipe between the muffler and cats?

[jerryp58]

Originally Posted by Nyjd516

Well what about performance, would 2.5inch piping from the cats all the way back to muffler and exit pipe be good or is it too big of pipe between the muffler and cats?

I don't think going to 2.5 would hurt anything; you should be getting the back pressure you need from your manifolds and the rest of the system. I don't think you'd notice any performance gain though either. I recently put a Magnaflow cat-back system on my 4-cyl and even though I can't tell any performance difference, it makes me feel better knowing that my 2.5 cat outlet now matches up with the pipe behind it (the factory pipes behind the cat were 2" -- go figure).

[Nyjd516]

Well what if I eliminated to two aft cats, will that throw any codes? If not then maybe 2.5 inch pipes to a muffler then 3 inch exhaust, I don't wanna do 3 inch piping through the hole system because I don't want to lose torque

[speedfoos]

2.5" is way too big for one side of a 3L V6. 2.25" is the biggest I would go. Think about it. That's like putting 2.5" exhaust on an old 3-cylinder Geo metro. Way overkill.

[Nyjd516]

Well what about the cats? And is 3 inch to big after the muffler?

[speedfoos]

Nope. Here's my setup.

Stock mani --> 2.25" piping --> glass pack \
.................................................. .......Edelbrock X-Flow muffler --> 3-inch 24" glasspack --> exit
Stock mani --> 2.25 piping --> glass pack /


Secondary kitties are removed. The only stock on the system are the manifold/primary cats. I ditched the stupid stock y-pipe as well and use the Edelbrock muffler as my crossover point/merge now.

[Nyjd516]

Ok I see, I'll do some more planning

[speedfoos]

To answer your original question if changing only pipes between secondary kitties and the muffler and its effect on exhaust tone - the answer is no. That stock muffler is giant and does a good job muffling. If you pulled kitties, it would be louder.

I bought a 2.25" dual exhaust builder's kit (not vehicle specific) that had everything I needed, then hit Uncle Summit up for the glass packs ($20-25 each), the Edelbrock muffler (around $90) and a couple pieces of 2.25" flex pipe (gotta have that in an exhaust system. I had a 3" u-bend pipe and about 3' feet of straight laying around from another exhaust I did and that's everything I needed to fab up the new exhaust.

All told I think I'm $350 into my complete system in parts and I do all the welding and labor myself.