myron96

Can someone explain to me what this is, what it does, is it street legal, will it pass emmissions?! The horsepower gain looks good, but thats about all i know! Help!

JOhn

13BAce

The downpipe/presilencer and header/presilencer combos replca eall of the converters. So thet're not street legal. Your car isn't going to pass emmissions with no cats. If you can get around that then the power gain is worth the money.

ronarndt

Myron96- Do they actually do an emission test in Baltimore, or do they just look at the exhaust system? I had the RD downpipe and presilencer on my GTUs for 10 years in PA. Most mechanics are not familiar with the RX-7. They assumed the pre-silencer was the catalytic convertor, since the RB system is well constructed and looks like it came from the factory, rather than from someones aftermarket parts pile. The system is also LOUD, despite the "pre-silencer" name of the part.

myron96

ron,

Yes, they do do the emissions test in maryland, which is pretty strict...What I was thinking of doing was once I got the emissions test completed, then switching over. How loud is loud, is it unbearable loud such that I wouldnt want to drive to work each day? Thanks!!!

JOHn

Michael

iTrader: (3)

I just installed one on my '90 vert less than a month ago. I'm pretty sure you won't come close to passing any smog test. When outside my car I can smell the different fumes that the cat normally restricts. There is nothing that filters anything. The presilencer is more straight piping, but it muffles the sound quite a bit (still ouder than before, but compared to straight piping without any presilencer, big diff). The cat-replacement pipe w/presilencer replaces everything from the exhaust manifold to the y-pipe. I can feel the difference in power. Haven't dynoed the car or taken to the track so I couldn't tell you exactly how much it helps. I can definitely feel the difference though. Took my a 2 days to get used to the low end loss in my car (had to gas more before releasing the clutch).

Michael

iTrader: (3)

As to how loud it is? It is definitely louder than before. I would say that it's not obnoxious, but I feel bad when I start my car and it warms up the ports (idle automatically goes up to 3k when turn on car) late at night. When accelerating, much louder than before, it's a very baratone deep noise. When cruising at a constant speed it is not loud.

Flobb

Do either of those maintain proper back pressure in order to operate the six ports? I never did figure that out, but I've always expected the answer was no.

Michael

iTrader: (3)

yes it does maintain enough back pressure, or so I think (makes my car faster, so I would have to say yes). While installing it, I ran my car with nothing after the exhaust manifold on, it was loud as hell and didn't maintian back pressure. The O2 sensor (i think this has to do with back pressure and the ports, I could be completely off though hahaha) that hooks up to the main cat also hooks up to the presilencer, so it can detect how much back pressure there is. Inside the presilencer there is a little tube that detects this. Hope this helps, sorry if giving the wrong info

Xentrix

Ive got the RB header- pre silencer combo and it rocks, It still keeps the 6 ports working if you don't put the block plate in that is included.

listen to it roar
http://zeffy.novus-logic.com/media/exhaust.mp3

ronarndt

Myron96- A couple others commented on the loudness of the RB system. Guess it depends on your definition of loud. At wot, it is a lot louder than stock. Under normal driving, it is not too bad, although it has that "droning" sound that people describe at constant freeway cruising speeds. I drove mine from PA to NC when I moved and after the 12 hour trip had quite a headache from the constant noise. Probably for a daily commute it would not be so bad, but you will still have to figure how to get around the emissions problem in MD. I'd try to find out what the fine was if you get caught before I put the system on. I know in some states it's pretty expensive. Where I live now in western rural NC, the inspection mechanics used to be really lax about checking *anything*- they would put a sticker on anything that came thru the door. The DMV enforcement guys from the eastern "more civilized" part of the state came thru about six months ago and did a sting type crackdown and suspended the inspection licenses of almost all the garages around here. In MD, you probably have to live with the regs, whether you like it or not. Good luck.