I was planning on getting CZ High Flow Cat and leave my stock exhaust on as he and others have done. After calling CZ, I learned that their cat was on a 4-5 week backorder due to a mod to the cat. I then spoke to SR Motorsports concerning their high flow cat. I was reluctant because I did not how loud the unit was. I decided on the SR Motorsports unit and ordered it with a 2 day delivery. It arrived today and I had Mazda put it in today as well.
The Mazda tech told me the unit was a good design, in fact better than stock because the stock unit has the O2 sensor attached at the bottom of the cat. In fact when Mazda put my car up, they noticed that I had scraped the bottom of my car and had damaged the o2 sensor threads ( they saved the unit and I observed the damage). The SR Motorsports O2 connection is at the top of the cat, whcih protects it much better.
When I got in the car, the cat was no louder at idle. When I hit 5k and up the sweet rotary engine sound is evident but not obnoxious. I really dig the sound when the car is pushed.
I have become a SR Motorsports believer, since I have their pullies, 9.75 flywheel and now their high flow cat.
My next and possibly last mod will be the stage 1 module once I am sure it has all bugs out. At that point, with all my mods, I should have about 265 HP at the crank, which I believe is close to max HP for NA engine.

 

Cool, I was looking for someone who installed the High Flow CAT Midpipe from SR. What does the "sweet rotary engine sound" sound like? Any sound clips to post?

 

What about their mid pipe.. are you going to get that too?

 

I'm pretty sure the midpipe is the replacement for the hi-flow Cat. Conv. that he just bought. All a mid pipe usually is a straight thru pipe that eliminates the cat.

 

http://www.srmotorsports.com/RX8_Per...tem_Parts.html

 

no.. I think they are two seperate parts

 

you can get a street legal mid pipe with a hi flo cat on it or an off road mid pipe without a cat but it's one part whichever one you get.

 

No it's actually one piece. A midpipe consists of either a hi-flow cat & resonator, or a straight thru pipe & resonator. If you read their website they have the straight thru pipe with resonator on their project car right now. They had the hi-flow cat w/ resonator on it before (they took it off). The straight pipe will almost always yield more hp, but it is illegal (off road use only) and it damages the environment. The SR midpipe part that you are referring too would replace his SR hi-flow cat (& resonator) that he just put on. It usually goes exhaust manifold (headers), catalytic convertor, resonator, & cat back exhaust.

Take a look at the mid pipes here and it will tell you a little more :

http://www.rx8store.com/subcatmfgpro...639&1=654&2=-1

The midpipes replace the catalytic convertor.

 

Thankx for the clarification...

I see the difference now...

I too have SR Motorsports Flywheel and am thinking about getting the hi flow cat.. Would love to hear a sound byte if you can get it...

Those underdrive pulleys look good too but they seem a bit expensive....

 

What is the difference in hp and sound between the hi-flow cat & resonator, a straight thru pipe & resonator, and just a strait pipe. Also will a cat back exhaust with the midpipe add on make more it louder or softer? Do i need an O2 trick sensor? I want the most power with the least noise, and not worried about emissions.

 

The High Flow Cat passed the wife test today. She knew when I installed the K&N Intake, which still sounds good to me, but she did not notice the new addition.
I don't have a soundbite but I did a lot of research trying to make sure the car does not get too loud. That is why I have spoken to Maurice, Huff, Gregg from SR Motorsports and others. I have been very surprised how quiet the car is with the high flow cat. There is a noticeable growl above 5K but not below, especially if not pushing.
My next planned mod will be involved with the ECU, although I will be patient and wait a while to determine who else comes out with another option other than the Stage 1 mod for now. I may still get the Stage 1, but do not want to rush it.

 

Pictures man.. Pictures...

 

i need sound clips more than pictures

 

Yeh, I agree

Sounds man... Sounds...:D :D

 

Pic please :D

 

Did you happen to talk with them about the Mid Pipe with silencer and how much louder that would be? Or ... was your main concern having is street legal with the hi flow cat on there?

I am seriously considering this and the pullies.. seems like a good investment.

Thankx!

 

How is the Mid Pipe/CAT performing lately? I think it is my next mod - just looking to see if you are a happy camper :p

 

Just bought the Pullies and High Flow cat from SR... Along with tanabe sway bars front/rear.. as a side note...

I'll definitely create a write up after I get them installed next week sometime..

Happy days are here again haha....

 

Nemesis8
I am very happy I purchased the SR Motorsports high flow cat for a few reasons. The first reason is the relocation of the 02 sensor to a safer location even than stock. The unit was a well made unit and has been surprisingly quiet in addition to the K&N intake. Based on many suggestions, I am happy that I did not change my stock exhaust system.
A nice raspy sound is heard now after about 6K RPM. This is my last engine mod for now, there are no more bolt ons that are worth the money. I will be waiting for Huff to get a supercharger installed by Pettit Racing in the near future.

 

Oh.. you have a stock exhaust system huh

Well.. I'll let you guys know what it sounds like with the borla...

 

sounds clip pls

 

hi-flow cat & resonator = Loud
a straight thru pipe & resonator = Louder
just a strait pipe = Loudest Yes, louder.Only if you go without the cat completely, as in, just a mid pipe.

 

Sorry no sound clip-too lazy

In response to Omicron, the addition of the SR Motorsports high flow cat did not noticeablly increase the noise level, this is particulary because I have the stock exhaust system. Once you are at 5K rpm and over, the is a pleasant growl, not obnoxious.
The only negative is an increased odor of sulfur (exhaust fumes) at times.
I would still recommend.

 

I ordered the SR Motorsports high flow cat and pullies.. but cant install them because......... my borla exhaust broke... The left pipe leading out of the muffler got severed and left an inch long gash in the muffler.. woops....

They are shipping me out a new one but said it would take a few weeks.. sucks..

oh well.. another few weeks to wait isnt too bad.

 

What kind of effect would SR Motorsports' high-flow cat, or any type of cat, have on forced induction?