:bow:nice topic, i`m interested now because my fantasma doesn`t have the cat and its a straight 3" pipe from the downpipe to the muffler. i will run 550cc injectors and some mods on it "7mgte". post the results to see the diferences. thanks

I took my Supra without cat for a run down the mother road on Saturday. Had the top off and the engine sounds get annoying real quick. I do not think he has any more power than my Supra with the CAT. If anything there seems to be less power. Well put enough money into her, suppose it is time to replace the exhaust system or at least from the block to the cat.

so you feel more power with the cat?

I would have to do a series of objective tests. I do hope to get transferred to Hawaii or return home to Japan. The Cat is needed for both, do wonder if I can get in trouble for running without the cat.

I will post the results for sure.. Currently my car is....

Full 3'' Cat back exhaust from MaganFlow, and AEM intake..

Unfortunately the test may include a 3'' down pipe w/3'' turbo elbow.. Sorry, but it just may end up that way.. ;)

Oh I like a car that performs and thus loud is not required. Loud impresses teenagers and draws police attention. Having tinnitus from my military service and loud for loud sake is annoying.
The max speed limit is 75 mph 120 km in Oklahoma, I do not race but wants to have a good ride that makes the most out of the trip. Again Loud or giggles "load" is for children :rofl:

:naughty:i`m with you , BUT i want to have a ride that when those mustangs , camaro, :ghey:etc .. starts to accelerate next to you , showing off , you step on the gas and there you go , kicking some muscle ASS!!!!!!!

大きい廃物
 

I will leave it up to you to race the young boy in his GM or Ford sodai gomi "mussel car". I just to not have time to play with the kiddies ;)

Do keep in mind that the changing of the cat will only heavily influences N/A's on powerband issue. With a Turbo, all of the back pressure required by the car is supplied by the turbo, no further back pressure is needed.

So, If you got a turbo, sure, you can take the cat off and see a considerable gain.

With an N/A, I wouldnt, the car runs alot smoother with it on and it smells better.

One more thing to keep in mind, the oxygen sensor on this car is not heated, I have been to told by mechanics that beack pressure created by the cat helps to heat up the oxygen sensor, and that little guy controls up to about 8% of your fuel economy...

F' it all.. I'm either hollowing the cat or doing the test pipe.. Anyone know what kind of noise a hollow cat will make? something nasty added to my 3'' system? or will it not sound bad?