Powerpack

Yesterday I removed my cat because was getting clogged, but it seems it was still doing its job as a cat. Since I removed it, my car exhaust smells very bad when idling and I can't tell you right now if it's the same on the road. :frown:

Is it going to get a better breath when I'll have fixed my problem of lacking power or is it the natural RX7 breath? ???

Rob x-7

By bad, you mean very rich smelling? No, thats normal, hence the reason Im putting a converter back on. Only one though, a high flow, instead of the 3 that were on there. And the racing beat pre-silencer that was solely on there before. There are 3 converters on that car by the way, you only have one??

Powerpack

No, I have 3 cats but the 2 pre-cats were broken inside so I just threw the stuff out last year. Now I removed the 3rd but as I said it's smelling bad. You said you're putting a new cat but high flow, it goes in the place of the 3rd and you have a RB presilencer behind that just before the Y.

Rob x-7

I believe that the Racing Beat pre-silencer takes the place of the main converter, its been almost 5 years since I put it on , so Im trying to refresh my memory, it comes with a pipe that goes in place of the other 2, so basically you run no converter, and a pre-silencer, the fumes that come out of the car with this set up SUCKS ***. It stinks you and your clothes up if you stand behind it, will stink up the house if the wind blows the exaust in a open window, and your car wont pass inspection, never mind visual inspection, it wont pass emissions testing , it will rev a bit better, and even show a slight improvement in fuel economy though. Im going to have the shop that did my exaust ( its all custom after the pre-silencer with Borla mufflers ), take the pipe down, and weld a high flow converter in its place, to be prefectly honest with you, I wouldnt reccomend running no converters on these cars to anyone, its one of those things you do thinking it will increase power, but on a N/A car that is basically stock, its something I feel people regret afterwords due to the fumes.

Powerpack

Yeah...I knew it was clogged and that I could have some smell problem but not that much. I can't put it back since I threw the stuff out like the other 2 and put a pipe through it to be less noisy (so I could re-use the flanges). But this was temporary, I wanted to install the RB Pipe/presilencer kit later. What brand is your new high flow cat?

Rob x-7

catco, $60 from summit racing, all the materials used in a converter are the same, this is a "universal" high flow one. Ill see how it works probably in the next week or so when I get my rims back from the polisher and take the car to the header/exaust shop.

Powerpack

I suppose it's in stainless steel. Are you going to get the same efficiency as the original cat, I mean for emission test if you have to be tested. It seems low in price for a cat, no? I'm going right to the web site to see what it looks like. I'm not interested to keep that **** smell either.

1Revvin7

with every thing good there is always a bad :yinyang: U guys are telling me u gained no power? My car atleast gained 10bhp, with removing my 3 cats, revved faster and past 4k it pulls so much harder, and i also get better fuel economy, but yes it does smell like crap. Sure u guys don't have exhaust leaks? Only ppl who smell it are the ppl behind me, and i never smell it when in my car, only when chillin back by my exhuast.

Powerpack

I did gain power and I'm sure it's not only because the cat was clogged. Judging by the first tests I made, I gained about 25 hp but I'd say that at least 15hp was lost due to clogging. I still have power missing for the expected 146hp though.



What I'm thinking about is 2.5in downpipe and a 3in high flow cat instead of the presilencer.

Rob x-7

< I want to live where you live where the wind always takes the exaust away from the car, lol. Sometimes I have to watch if the house windows are open and the wind goes a certain way, it goes in the house. And with a convertible in traffic or at a light, if the wind is going a certain way- it also comes in the car. With the windows closed or while driving, its fine, if there was a leak, I would smell it in the car when the windows were closed. My point is running a exaust on a stock N/A car, I think people should save thier money on the pre-silencer that hardly silences the car anyhow, and invest in a good high-flow cat. Here in New York, cars are run on a wheel dyno and tested, and its on video camera, there are guys who can still pass cars, but if the car is stock, why not have performance and be legal? For example: my cousin has a ZR-1 corvette, the car was made so right from the factory, that even with a $2500 aftermarket exaust on it, it basically ran no different, it just spewed more emissions in the air, so he sold it on Ebay and went back to the stock exaust. To each thier own, but if it means 5 horsepower, im going back to one high-flow over the original restrictive 3 that the car came with.