By 1BADJK. He tried multiple muffler/exhaust combos and dyno'd them inbetween. It's on a thread around here somewhere. Do a search.

 

Yes I've tried just about every exhaust combination and Dyno'd between them all... Currently we are trying a set of Headers of a 2002 Pontiac GTP.. THey bolt right up... They are much larger than our stock headers.. Just got a set in my hands... Will be trying them end of next week.. Will be a much cheaper method gettting headers.. They are tons of aftermarket bolt on out there for this 3.8L... Just need to find out which ones fit.. The aftermarket for the Pontiac is so abundandt.. I will pllay and figure out what I can..

 

Your claim in your previous post was that it was "Dyno Proven" that it wouldn't improve power so I'm curious where I can find your source? I searched and couldn't seem to locate that thread...

 

Here's one of many..

https://www.jk-forum.com/forums/show...hlight=results

.

 

The thread starter makes no mention of removing the cats that I could see...

 

Your Correct.. It wasn't until later we started playing around with the cats..
Removing the lower 2 cats yeilded a loss of approx. 1.5 FT .Tq.. . But did gain approx. 2.2 Hp.. in the upper rpms.. Say 3250 and up.. It seems this motor needs that little extra back pressure.. As also proven between the True dual system vs. 2 into 1 collected setup.. After I dyno my Headers this next week.. I will try to compile a complete list of setups I tried with Dyno Sheets..

 

Somehow this post lead me to another thread, and finally to the Magnaflow website. This must be their new Zero Emissions exhaust with two inlets and no outlet. Why didn't I think of this Pic taken directly from their website!

 

That would guarantee you some back pressure.

 

ok hear is the deal with the o2 sensors and cat converters
the jk just like the tj have 2 sets of o2 sensors and 3 cats
it is made up as the following read closely
manifold then first o2 sensors these sensors monitor the exhaust and tell the ecm to adjust air fuel ratios they cannot be eliminated under any circumstance
then the exhaust goes through the pre cats or resononators or whatever slang you have heard they are called in actuality they are mini 4 way catalist (cat converters) then come the second set of o2 sensors they measure the change from from the first set and tell the ecm that the cats are indeed working within normal parameters these cant be eliminated but they can be tricked with o2 simulators and any good exhaust dude can fabricate an intermediate pipe with out the cats now for the last one it can be taken off or replaced with a high flow racing cat
unless you are going to put a real supercharger with a hell of alot of boost dont touch it its just not worth the gain or loss or the money or the fine or the planet
mods are great when done properly this is the 21st century and unless you are trained in auto electronics fuel injection and emissions (and i dont mean a chiltons manual) dont play with it
FYI i did this to my tj banks header custom pipe o2 simulators random technology high flow racing cat converter and a banks monster cat back system all dipped in jet hot coating cost $2500. and i only did it because i had a super charger with 10 psi boost real ram air and a modified intake and head
except for the cool sound it made it would have been stupid and or use less
get a CJ build a monster carburated V8 and have a blast
I DO NOT MEAN TO OFFEND ANYONE WITH THIS POST AND I DONT CLAIM TO BE AN AUTO TECH,A GOVT OFFICAL OR A SAVE THE PLANET CRUSADER

 

i think for the money that little magnaflow straight through muffler is a good mod it will sound good and do what the $500 cat back systems do
as far as a cai buy one for $200 or build one out of scrap tube and a cone filter for $75.00 paint it whatever color you like
i hope everyone who see's this post thinks before they just go out and buy stuff
all prepackaged systems no matter what they are for ....cars.... food whatever are for profit you are paying for the box and advertising and shipping and the salesman hourly wages and the cool writing on it and the polish and yada yada
i am not bashing any manufacturer i just know this is a jeep not a custom tuned race car