I changed out the stock cat to rx8store.net's high flow cat and wanted to tell you what I thought.

I used 3 - 7/16" x 1.5" stainless steel bolts with lockwasher and nut for the flanges to the exhaust manifold. I used 2 - 3/8" x 2.5" stainless steel bolts with lockwasher and nut and fender washer for the springs, these bolt up to the muffler pipe. All of these were fine thread bolts. those last two bolts skrew into the the flange so I put the lockwasher and nut behind the flange just to lock the bolts in place since you have a spring on those bolts.

Piece of cake to put on and take off, had to unclip the wire for the O2 sensor and unscrew it off of the stock cat and then back in the bunge for the new cat pipe. I have had no cells so far and the engine revs faster, it doesn't lag like it did before. It is of course louder than stock but you can granny drive it to keep it quiet through neighborhoods or by cops.

I have the Mazdaspeed sport exhaust and it sounds awesome when you step on it. The Mazdaspeed exhaust sounded great with the stock cat and now it just really emphasises the sound with the high flow cat.

I can tell that there is more horse power, might not be much but to me it is noticable. Love it.

 

How hard was it taking off the OEM cat? It wasn't locked in place? The bolts were pretty easy to remove? If there was some challenge what did you use?

 

I forgot to mention that I had to take a cross member off. I think that is what it is called, it is a short piece about a foot long that had 4 bolts holding it up to the frame. couldn't get the cat to drop down untill I took it off. See the ratchet wrench and the can of wd4d, that is all it takes. My car is an 04 and the bolts were on just tight but not gut wrenching tight. I replaced the muffler about 4 months ago so those two bolts were easy because of that, but from what I can remember they were not that bad back then.

 

I have just sent an email to Rotaryperformance canceling my Supercat order. (Placed the order late may) I think I will order one of these Is it all "bolt on" ? Do I need to buy any nuts and bolts?

Thanks

 

It is a bolt on but you need to get your own bolts, the ones on the stock cat are pretty much on for good. I could not get them off so I went to the hardware store and got the stainless steel bolts nuts and washers. it ran me about $17 for them. Yeah stainless steel bolts and nuts are not cheep. I reused the crush washers that were on the stock cat and there is no leaks so they were good for me to reuse.

You could ask rx8store.net if they have a kit for bolts and gasket, I just didn't think of it when I ordered.

 

I have just sent an email to Jason

Thanks woodysjh

 

got any sound clips?

 

Have you shot flames with the High Flow Cat & MazdaSpeed Exhaust?

 

Yeah I just made this

About 22 mb file

MS Sport and RX8Store.net HFC

 

Check out the video, I haven't seen any flames. The cat does a good job and I do not get a cel. I think the high flow cat is a Magnaflow cat.

 

Very cool sound on the video

 

how much did you pay for the whole thing?