v8 exhaust question

[keegsxplorer]

hey all, i have a 2004 EB v8 and recently put on a flowmaster 40 series exhaust. i told the guy who did it to remove the resonator also but he looked and told me there is no resonator and that i have three cats.......Is this correct?
no resonator and 3 cats?
TIA

 

[Slowlyvverot]

I'm not sure about yours in particular but IIRC 3rd gens have a whole range of various cat layouts. I remember hearing that they can have up to 4 cats.

 

[keegsxplorer]

hhmm...i was just suprised that there is no resonator and how quiet the stock muffler/exhaust is i assumed there had to be a resonator but i guess not

 

[zerodevil]

yeah its 3 cats (one on each part of hte y pipe + one before the muffler) and a resonator before it exits on the back of the truck.

 

[Limited02]

Hmmm, then I guess I removed the third cat. I keep getting confused between it being a cat or resonator. From what I remember, there were three cats, then the muffler, then nothing by factory pipe all the way out the back. (No resonator or anything larger than the factory exhaust after the muffer?)

Legally shops cannot take cats off. But if you show up with it missing like I did, then you should be good I actually just cut mine off, welded up a 3" pipe into a 40 series dual out with dumps. Too loud and then I had a shop change it to the current setup with 2.5" exhaust and I love it much better.

 

[keegsxplorer]

thanks for the replies.....just got this as my daily and still learning about it..... use to working on my vw but she will be put away for winter so i'm starting on this beast now....thanks again

 

[Rofocowboy84]

I've heard both opinions on the thing before the muffler. The way I see it, the O2 sensors are before it, so it doesn't count as a cat in my book. The thing just before the tailpipe isn't a resonator, as some people think, it's just a heatshield for the spare.

 

[1_v8_merc]

Yeah the last exhaust guy i had work on my mustang, he found out my Pre-cats were blown. He told me it's a PAIN to re-weld new ones in there, because there's no room at all, and they had to be put in at a semi-vertical angle.
He told me he would yank them out and put pipe in there instead,lol, THAT'S how much he hated Cats,lol.

It still passed emissions too.

You'd be surprised how many Cat's you can yank off a vehicle and it will still clear emissions no problem....factories put more then they have to....to make money and so there's a much better chance that they will clear emissions for a while even if they are losing their effectiveness over time.