I don't have any experience in car tuning, I just got an 05 6spd GT and am planning to replace the cat with a resonated midpipe, I have been doing my research and found quite a few companies producing midpipes, for now I am leaning towards the one made by RP. (I am not planning to do any other modifications to the car except the midpipe and the intake.)

1.Can any one offer some opinions on which resonated midpipe works best?
2.Am I going to have any kind of codes (CEL) running because of the installation of the mid pipe? (some of them say that there is no O2 simulator needed).
My limited knowledge leads me to believe that once the midpipe is installed I will have to reprogram the ecu, in order to get the most out of this modification.
3.Is this necessary, how dramatically will this (re programmed ecu) effect the increase in power?
4.Are are there any videos/ sound bytes of cars with resonated midpipe installed. How dramatic is the increase in loudness.
5.Finally are there any dyno/acceleration results (before and after midpipe) for cars with just the above mentioned modes done.

 

if you just put a mid-pipe (no cat) you will have a cel it' will read cat-converter efficiency below threshold or something like that. you will also be dumping gas everywhere you drive since the 8 runs rich...personaly i hate the smell...that's why i went witha high-flow cat from RP not their catless midpipe. no cel's and she sounds great (i also have the REVi and REV8). install was easy (i had access to a lift) jus tdont' do it when the car is hot...lol

as for the ?'s about dyno's and sound clips..there are a few...do a search as i have forgoten the threads they were in

 

Agreed, a catless midpipe will shoot flames I have a few clips on my server. Click the sig and enjoy.

 

Thanks for the replies

Nemesis8: Great sound, how much of it is due to the REV8 Cat Back Exhaust? I will probably not get such a deep throaty sound with just the RP Super Cat.

Army_RX8:

So you got the Super-Cat replacement pipe from RP? What kind of a difference did it make, butt dyno - responsiveness/hp increase? Did you do anything with the ecu?

thanks

 

no ecu is stock...butt dyno tells me that it added a lill (nothign huge) but if i can feel it then it can't be too bad (~10hp + o r- )...but i also have the REVi and REV8 (intake and exhaust from RB). when i shift i dont' take my hand off the stick until i get in thrid..b/c the cars goes through the gears so fast i like it..sounds great too...not overly loud when just driving around..but when you get on it (WOT) you can tell it's there

 

Good question, I had the REV8 first, but when I added the RP it got really throaty. It would be nice to hear the RP with a stock exhaust. Anyone have that setup?

 

not that i knwo of..most people get a cat-back as one of their first mods..lol so everyoen who goes with the midpipe (high flow or other wise) normaly already has some kinda aftermarket exhaust

 

I have a B&B midpipe with the stock catback. Unfortunately I don't have a sound clip for you but at high rpms the car sounds like a "jap bike". Everyone who hears my car including RX8 owners, seem to love the sound. You can really hear the car winding up without much of a throaty sound at all. I did have the B&B catback on with the midpipe at one point, although the packing started loosening too quick and it started sounded like robotic farts, or a freekin ricer mobile. Anyway I'm hoping to get the Racing Beat catback to go with my midpipe in the near future.

 

Devious12:

So are you getting CELs and dumping gas?
Did you measure hp or 0-60 ?

 

Does anyone have expirience with the SR motorsport High Flow Catalytic Converter?

 

I heard that if you get the RP you have to have someone weld it on for you cause it does not come with a hanger or something? This true? Also would like to know about the SR Motorsports high flow cat.

 

The RP supercat doesn't come with a hanger because it light and they thought it wasn't necessary. A few have had rattle problems because of it though. I think Nemesis had the OEM hanger welded on. I'll let him speak.

 

yea the rp cat weights about 1/3 of the stock one..i ahve no rattle issues....if i do i'll just weld a hanger on myself

 

Spoke to both SP and RB regarding high flow cats.

SP: about 8-10hp increase with just the highflow cat. Said the stock catalytic is really restrictive.


RB: "we do not really believe in high flow cats for this car, since a high flow cat is still a cat and is thus still restrictive", so they don't even have it under development, their estimate an increase of about 2hp.

So as you can see there is a difference in philosophies here.

RP seems to side with SP on this issue, I have not talked to them but their website dyno chart shows a maximum of 9hp increase at about 8400rpms.

Note: All of the numbers motioned here are solely for the highflow cats and do not include any other mods.

So as you can see there is a disagreement on numbers or facts between RP & SP and RB (not opinions since they are proven by dyno results).

I am still inclined to get a high flow cat, the question is which one do I get? SP says that theirs is street legal, while RP is says:
"It has been tested several times and can pass a smog test with flying colors. Because this is a new design, CARB and Federal emissions certificate is pending. This is a perfectly street-able cat system but is for off-road use only."

I am leaning towards the one that is made by SP but have to act quickly since their discount ends this Friday.

Your opinions are welcome...

 

their discount has been ending fri for about 6 months. go for it.

beers

 

Swoope:

i kinda of thought this but was not sure if this is the case

do you have one?

 

I have the RP with stock exhaust...

- idle its very deep and pops a bit
- there is a resonance that causes some drone in the cabin at 3500 rpms (or 70mph), otherwise cruising and around town there is little difference
- between 4-6k i have an obnoxious ricer buzzing sound (not sure if its the engine note, an exhaust leak, vibration, ect)
- above that it sounds like stock but louder

 

i have a straight pipe with a borla resonator on it right now. it is the pipe and my car are being used for the interceptor x testing.

it really does sould good, but i would not want to live with the smell and the flames. scared the hell out of myself sunday night.

i have it from a good soruce the rp pipe is the way to go.

beers

 

Be aware of the SR motorsports claims are less then reliable....I would not trust them for sure. I dobelieve Racing Beat and what they say.

 

I've had a CEL for almost 1 year since I've had the pipe. I'm dumping way more gas than when I had the cat on you can smell the difference and I spend more on gas than I did when I had the cat. I had a mustang dyno last year with the midpipe and B&B catback @ 192rwhp. Since then I haven't tested the car with just the stock catback and B&B midpipe. Sorry no 0-60 times.

 

Jaguar_MBA:

What are you basing this on?