For those that have gutted their cat, what are the positives and negatives? Do you get attention from the cops? Is it really that smeally? Any data with the butt dyno, like a graph or something?

I Have gutted my cats, but left all the other emmision stuff. It doesn't smell that bad, but I wan't to know if the person driving behind me will notice....

Thanks in advance for the input...



Gi.

 

have a buddy with a car?

 

it smells realy bad, everyone that drives behind me says their eyes burn. so ya cops will probably notice

 

I had an RB turboback with no cat, people behind me that had windows down and all said it smelled, but didn't make their eyes burn or anything. I've had lots of cops behind me and I never got pulled, even with my failed inspection sticker. Inside the car it doesn't smell too bad, but I never drove behind it so I never smelled from there.

 

Well, if you gut your cats, your mufflers will soon follow, lol.

You can expect some decent power gains. It will be louder and a lot smellier though... haha.

 

Either there's something really wrong with your car or you guys are using something really freaky for fuel over there, coz I barely noticed any difference in smell. And burning eyes! WTF?

I replaced my cat with a straight piece of pipe, and got a nice power increase due to the cat being very clogged. It was also a little louder.

 

mines also stinks to high hell. when i get my oil changed and they say, turn her on to see the pressure, i hear the screams from the guy under the guy say shut her down hahahahaaha. i know my emmisions are killer. i cant drive with just the moonroof open cuz my eyes water up lol.

 

i can smell it a little but its not bad..and i agree with nzconvertable that i got a very noticable power gain since the cats on my car where original and clogged to holy hell. it does alter the sound to a sound that i pesonally dont care for, but with the stock y pipe and cans its not enough to draw much attention.

 

I have a Pettit hi-flow cat and my car still stinks! But I'm running really rich and I premix. I love the smell, although I don't think the people behind me appreciate it so much. My friends won't even drive behind me...

 

I have been driving, for the last two days, with the windows and sunroff closed and open and i can hardly smell it. I quess ill me OK then....



Gil

 

ONe more thing. Have you guys gotten better gas milage as a result of no cats? THat is one of the reasons I did it.


Gil

 

eh, I smell a lil more like a weed eater after drving my car but I dont notice much differance. Flames out the rear are bigger. But I have no emissions or airpump etc. also so....

 

I smell like exhaust every time I drive it, especially with the windows down. My TII is horribly untuned and totally lacks emissions; it wasn't nearly as bad with my GXL.

 

Hehe, yea. I call it my 7 cologne.

 

i have a straight pipe exhaust to a monza cat back, its loudish. it smells,(bikers hate me at lights), and will pop out a lilltle flame here and there, which is good for an S5 NA i suppose

 

Wow, What it worng with your guys cars?

I've been running catless for almost a year now.

Rb 2.5 dp to presilencer to corksport 3 inch single.

It's ******* loud. You can hear me coming a mile away.

I never had a TII before this exhaust but I pulled 180hp and 182tq on the dyno and I just did a 14.9 a couple weeks ago on my second run.

I just ported my wastgate and can now boost high since I don't creep.

 

My race car is still nominally street legal. At the track I run a RB header and presilencer. When I need to get inspected I swap in a large cat.

It's not horrible but without the cat it is noticably stinkyer. Power and noise is indistinguishable betwen cat or presilencer.

ed

 

my GXL has a bonez cat replacement pipe w/ silencer and stock mufflers. I had already "fixed" the 5-6 ports to run off the airpump. The seat of the pants is cool...really opens up after 5k. Smells like an outboard motor in/out of the car. The sunroof can suck in some fumes depending on window positon. Sound is great....not too loud, plus you get that cool rotary "burble/krackle" when getting on/off the throttle. Luckily we dont have emissions tests here.

 

mine smells like a 2 cycle boat motor.

 

Everyone says my car stinks like hell when driving behind me. RB 3" turboback system, walbro fuel pump and 720 secondaries. I've grown immune to exhaust fumes.

 

go to www.summitracing.com and search for "fuel addetives" they have stuff you actually put in your gas and it makes it smell like grape or whatever you could possibly want.

link: go to first product on page

 

Thats crazy, to bad it 9.88 bucks for a 4oz bottle and it isn't good to the Oxygen sensor.

That is still kool thow....


Gil

 

dayum dude, thanks alot. i just ordered 4 cans of the stuff. 4 diffrent flavors to see which i like best haha. thanks dude. cuz my girl hates going out and smelling like gasoline jajajaj how i love that bitch

 

Don't gut your cats, replace them with either straight piping or a resonated midpipe. I gutted the single cat I had, and boy howdy did that sound bad. The cat was thin-wall metal, so it sounded like an empty muffler. Yuck.

 

Removing an airflow restriction from anywhere in the enigne will improve volumetric efficiency. With no cat in place the engine does not have to work as hard to push the exhaust out, so more of the power generated by the engine makes it to the back wheels. Converselt, the engine does not have to generate as much power to get the same amount of power to the wheels as before. So if you drive just like you used to, you will use less gas. But if you regularly use that extra power, you will not.

That just means your engine is very poorly tuned. Do you have any form of fuel control to compensate for those fuel mods? If not, or if you do but it hasn't be tuned properly to suit the mods, then your overly-rich mixtures will cause a stinky exhaust, not to mention excessive fuel consumption and power down from what it could be.