Hollowing Out Cat?
 

I hear all this talk of spending $400 for a midpipe which is the same as the pipe that has the catalytic converter but without the Cat. What if I hollow out the Cat (take out the pourous rock inside) ? and just put a o2 sensor fooler? wouldnt that be the same exact thing, but in reality having a "Cat" housing under the car for police stop purposes and just have to buy the 02 fooler. dont you think it would be more logical to just hollow out the cat and put the sensor fooler and it looks "legal" and its a hell of a lot cheaper and it will be the same effect of going cat-less?

Comments please..... maybe i'm missing something.

I think that would be REALLY LOUD!!! But, if thats want you want then do it. RX7.com offers a good midpipe. I got 1 for my 7 and its pretty quiet.

The big advantage of getting a midpipe is that you can run illegal-spec when drag racing at the strip or on the road course, but can re-install the cat for legal running on the street. Is the 2 or 3 hp advantage really that important to you that you need to increase the pollution output 100% of the time driving on the street??

Regards,
Gordon

Correct me if I'm wrong but I think the empty chamber will cause some turbulance and will not flow as well as a mid-pipe. Either way it's almost the same.. I did it to my FC and FD when the cats went bad. Until I got new cats of course :)

I dont want to do it, but im thinking its the same thing as using a midpipe? I dont want to void warranty but i had heard about that before and it seemed like the better option or if its going to cause more turbulence then run a 2.5 inch pipe inside so that it would just be a midpipe but with the Cat housing around it makes it look legal? and wont the mufflers muffle the sound output ? isnt that what they are for?

If one absolutely has to do this, then the pipe through the middle of the cat would be the way to go. No turbulence that way, just straight through flow, exactly like a midpipe. Well, an overweight midpipe wearing a heavy parka, that is. :D

As for sound, a midpipe with no resonator will definitey be a lot louder than the same car with the stock cat in place, because the cat effectively act as a pre-muffler (or resonator). Without it, the sound coming into the muffler will be proportionately louder. The car will be louder as well, as any muffler just reduces the sounds coming into it by some percentage.

Ohh ok, thanks for clearing it up

You betcha. :D

"Is the 2 or 3 hp advantage really that important to you that you need to increase the pollution output 100% of the time driving on the street??"

From what I've seen on the different exhaust systems, adding a midpipe and catback has a 19-22 whp gain potential.

I agree

Tommy,

The Midpipe made a big difference on my car. Its well worh the money. Here's my review on the on the Midpipe:

https://www.rx8club.com/showthread.p...5&pagenumber=8

what ever happened to just getting a muffler shop to just custom bend and weld one for you??? $200 midpipe vs. $75 custom midpipe...

XDEEDUBBX,

A lot of Shops in Miami wouldn't do it since it is a federal offence.

we need to get together i have to hear that thing, and since im completely stock i want to run them side by side to see how the intake and midpipe do, see how much pull you get on my car, email me with your cell so i can call you

Tommy

I had to add a resonator to muff the sound a bit. Call me so we can try it out.