DISSECTED CAT

[SPYD3R]

I 'DISSECTED A CAT' TODAY......

an RT Catalytic Converter, that is..... and i would agree with Picklehead, that it is a "pre-muffler", not just a CAT....

i'll be gluing this bad-boy back together next week, so if any of you need pix at different angles, let me know now b4 it's closed up...
SAM_1032.jpg SAM_1034.jpg SAM_1035.jpg SAM_1037.jpg SAM_1038.jpg
see more pix in next post...
dp

[SPYD3R]

DISSECT CAT 2
SAM_1040.jpg SAM_1042.jpg SAM_1044.jpg SAM_1045.jpg SAM_1046.jpg
the FAT STUBBY section in the middle, is the CAT... it remains in but is no longer 'active'... i left it there only for support, and because it would have been too difficult to remove with the tools at hand...
any questions...?
Dan P
Easley, SC
SPYD3R

[coz]

interesting to see the inside. i can only say, what a big piece of un-necessary overkill, crap. i'll never get why it has to be that overbuilt and huge. nice work though. carry on......

[Bob Denman]

Dan,
Do you see any useful way to hook a "Hot-Dogger" to it?
(In case you've never seen one; it's a metal box that you hook to an exhaust system, and cook your lunch in, on the fly!)

[jthornton]

Very interesting to see the insides, thanks for sharing that.

JT

[SPYD3R]

Dan,
Do you see any useful way to hook a "Hot-Dogger" to it?
(In case you've never seen one; it's a metal box that you hook to an exhaust system, and cook your lunch in, on the fly!)

BOB;
send me your CAT, and i'll convert that sucker into an oven that you would be proud to cook your Thanksgiving turkey in.....
Dan

[Bob Denman]

I'd have ALL the dogs in Town chasing me...

But not to cause harm; just to get the recipes!

[ShadyGrady]

Fantastic job Dan. Thanks for sharing the photos - now I know exactly what to expect when I gut mine.
ShadyGrady

[tip]

A TIP OF MY HAT AND A THANK YOU FOR SHARING THIS.!!
I would be interested to know if the cylinder pipe that shows the most heat (2nd photo - sideways) will now run cooler because the exhaust has a straight shot out now.Also curious about the effect on the other cylinder temp - should be better also - but there is a difference in the exhaust exiting.
My 2c and congratulations on undertaking this project!!!
Tip

[Chupaca]

you have put my wondering to rest. Now I know whats inside even if I don't have one...

[Big Bird]

Danny... looking good... who'd thunk that me giving you my ole Hindle would lead you down this path... great job.

[PMK]

Interesting build. Seems a double walled shell with insulation between the walls.

Performance wise, and sound wise, prior to gutting it the back pressure of the cat tube may have stabilized the pressures in each chamber.

Gutted, the shape and size looks similar to a resonance chamber. Curious to see how it sounds and performs.

Almost too bad, you did not spend a bit more time and model it after a Flowmaster style muffler. Low back pressure but enough to keep decent torque if done right.

PK

[SPYD3R]

Danny... looking good... who'd thunk that me giving you my ole Hindle would lead you down this path... great job.

THANK YOU BIG BIRD, the Hindle is back on.... u b da best...

[SPYD3R]

Interesting build. Seems a double walled shell with insulation between the walls.

Performance wise, and sound wise, prior to gutting it the back pressure of the cat tube may have stabilized the pressures in each chamber.

Gutted, the shape and size looks similar to a resonance chamber. Curious to see how it sounds and performs.

Almost too bad, you did not spend a bit more time and model it after a Flowmaster style muffler. Low back pressure but enough to keep decent torque if done right.

PK

PK;
i haven't glued it back together yet, that's todays project, so it wouldn't be too late to model it after a Flowmaster (i've already done one like that on an RT muffler that had the CAT removed... and the SOUND POLICE on the Dragon ticketed him for $400)... the only thing is, if i did model it that way, there's another muffler that is down-stream from the CAT that would negate any tone made by the modeled CAT... it's like trying to push a chain... doesn't work...
thanks for the thought however...
Dan P

[PMK]

PK;
i haven't glued it back together yet, that's todays project, so it wouldn't be too late to model it after a Flowmaster (i've already done one like that on an RT muffler that had the CAT removed... and the SOUND POLICE on the Dragon ticketed him for $400)... the only thing is, if i did model it that way, there's another muffler that is down-stream from the CAT that would negate any tone made by the modeled CAT... it's like trying to push a chain... doesn't work...
thanks for the thought however...
Dan P

Was unaware that you had done that already. Guessing it was pretty loud or just the wrong something to get a $400 ticket.

I would have suspected that a modded cat with an oem second muffler would remain pretty quiet.

The Flowmaster clone idea was more focused towards some back pressure to retain more bottom and low mid range torque.

Either way $400 is a bummer for excess sound.

I enjoyed the photos of various cut open cats on the Spyders. Personally I had plans to mod ours on the 14 RTs, but got lazy and bought a bypass pipe from PitBull. That with an oem second muffler has proven acceptable for sound level and tone, plus seems to have added some mid range pull. Guessing that is based on the overall longer tube(s) prior to the muffler / baffles.

PK

[robtdonna]

Has anyone had any warranty issues regarding replacement of the cat with a bypass?

Personally I had plans to mod ours on the 14 RTs, but got lazy and bought a bypass pipe from PitBull. That with an oem second muffler has proven acceptable for sound level and tone, plus seems to have added some mid range pull. Guessing that is based on the overall longer tube(s) prior to the muffler / baffles.

PK

[PMK]

Has anyone had any warranty issues regarding replacement of the cat with a bypass?

Warranty issues, honestly, so far I have done all the work and our machine has not been back yet.

I say "yet" simply because the items I plan to seek a warranty claim on are a corroding floorboards under the rubber mats, maybe a poor left front tire, and a failing left mirror. None deal with the engine.

According to the often stated and quoted Magnessun / Ferguson act, seems warranty can not be denied from changes or mods unless proven to be the cause for failure.

The OP showing a cut and gutted cat is really pretty cool, informative for those wanting to know, and obviously not for everyone or the weak at heart. Personally I enjoy serious mods and prefer, when possible, to accomplish mods that are stealth, so virtually unseen.

FWIW, swapping to a bypass pipe on a 14 may not be for everyone, but since many people MUST HAVE reversible at no expense mods, it's a good mod if you do your own work.

PK

[spacetiger]

Good thread. Good to see exploration done like this with good pics. Thanks for sharing.

jerry

[KX5062]

Very interesting to see the insides, thanks for sharing that.

JT

Agreed.

[MikeinGA]

DISSECT CAT 2
SAM_1040.jpg SAM_1042.jpg SAM_1044.jpg SAM_1045.jpg SAM_1046.jpg
the FAT STUBBY section in the middle, is the CAT... it remains in but is no longer 'active'... i left it there only for support, and because it would have been too difficult to remove with the tools at hand...
any questions...?
Dan P
Easley, SC
SPYD3R

Great job Dan. Did you take any heat readings before, I would like to see the difference after. I could bring my laser thermometer to a lunch ride and test a stock to the modified cat. My Spyder is still in the shop.

[Bob Denman]

Personally; I'm disappointed...

The Title to this thread says "Dissected Cat"...

I was expecting a biology lesson!

[SPYD3R]

Great job Dan. Did you take any heat readings before, I would like to see the difference after. I could bring my laser thermometer to a lunch ride and test a stock to the modified cat. My Spyder is still in the shop.

TOO LATE MIKE....
i couldn't find any1 that wanted it... so it's in the trash...
i just was curious as to the configuration of the INNERS... 2 pipes in, the exhaust bangs up against the back wall, does a 180 and passes thru the CAT, again bangs up against the front wall and finds it way into the outlet then off thru the muffler.... very simple... but I truly had to scratch me head on this one... i dissected a dozen RS mufflers... they all have the CAT installed at the very front of the muffler, as you can see here: SAM_0346.jpg SAM_0342.jpg ... why the RT's have the CAT as a seperate unit is rather odd, and costly to me... jmho...
Dan P
Easley, SC
SPYD3R

[robtdonna]

Dan,

What year RT did you dissect? If it was earlier than 2014, wondering if the design is same for the three cylinder?

[SPYD3R]

Dan,

What year RT did you dissect? If it was earlier than 2014, wondering if the design is same for the three cylinder?

Rob;
it was a 2010.... and YES, there is a HUGE difference between the 2 cyl. and 3 cyl. CATs..... the 3 cyl. CAT has 1 pipe in & 1 pipe out.... a VERY simple pipe can be configured as a 'by-pass'... "how do i know" you ask.... because, last week i took a friend of mine with a 2014 RT-L to a friend of mine that owns a tire & muffler shop, and we had one configured... cost was around $50...
Dan

[jcthorne]

TOO LATE MIKE....i couldn't find any1 that wanted it... so it's in the trash...i just was curious as to the configuration of the INNERS... 2 pipes in, the exhaust bangs up against the back wall, does a 180 and passes thru the CAT, again bangs up against the front wall and finds it way into the outlet then off thru the muffler.... very simple... but I truly had to scratch me head on this one... i dissected a dozen RS mufflers... they all have the CAT installed at the very front of the muffler, as you can see here: SAM_0346.jpg SAM_0342.jpg ... why the RT's have the CAT as a seperate unit is rather odd, and costly to me... jmho...Dan PEasley, SCSPYD3R

It was redesigned for the RT because that muffler gets very hot right where the passenger's leg is located on an RT.