I live in michigan which has no emissions laws, and i was wondering if there is a noted power gain from removing all emissions. Thanks.

 

easy answer... yes..

 

........

 

Remembering that the 3 factory cats are "emissions" there's quite a bit of power to be gained here. Not only that, but lightening potential, and a cleaner look underhood. Some may argue that its negligable, but I think its worth it. Basically, the three cats can go, the air pump, and ACV can go. I know a bunch of other junk can to, but that's the basics.

 

Yea i didnt think about the cats....thats the only logical thing i can think of that would free hp. Why not just do that and keep everything else?

 

if i recall...racing beat stated that just changing the exhaust from factory, gave a like 30-40 hp gain....which is incredible...... so, if that is true, or anywhere close to it... then its VERY worth it! but the smog pump wont give you much gain at all........

 

^^^^^^^^^ Thats ethier the turbo2 or with a carb setup on a NA.

 

removing all emissions would greatly improve hp. As viper said though the smog pump wont do release much, it only really causes drag at idle

 

no a good header back system will free up 27hp as dyno proven by mazdatrix and 59hp dyno proven by them on a turbo II so yes cats suck and steal power

 

For the NA im almost positive thats with a carb setup. Ill check real fast just to be sure.


ok http://www.mazdatrix.com/r-ex86nt.htm it states with a full race exshaust you get a 28% increase in hp. So what is 28% of 146? Oh thats with FI.

 

i am looking at it and it doesnt really specify if it is or not it just says from a bone stock non turbo

 

Yea Racing Beat is the company that recomends using a carb with a header.

 

Let's cut through the BS...Ignore anyone who says that removing the emissions equipment will result in a power gain.

The ONLY emissions equipment that can be removed for a power gain are the cats. Pulling the factory cats and going to either an aftermarket high flow or a "straight pipe" will uncork the exhaust and let the engine breath as it should. Obviously to get full effect you need a catback, and you'll have to figure out some way to activate your aux ports (airpump, electronic, etc.). If you go catless and install a header, you will need to block off your ACV valve. There's no gain, but after the cats are gone there's no need for the ACV.

Removing the other emissions equipment like the solenoid rack, charcoal canister and "crankcase" breather (PCV) will result in absolutely ZERO power gain. In general, these mods make the car less livable and are totally pointless. EGR doesn't matter one way or another.

I defy anyone to produce back to back dyno runs with the only mod being what I have listed above and show a consistant and provable power gain. Most of the emissionless cars I work on run worse then stock because of all the hacking.

 

u dont call cleaner intake and air path inside the manifold a performance gain... i do lol.. i just did a head gasket on a cavalier and when i removed the intake i couldnt beleive it.. there was like an inch of black carbon from the egr ****... im just removing them cuz i hate emission and i wanna stick it to the man.

 

Cavalier? After reading that it's probably not worth replying...

Unlike a piston engine, the rotary does not really produce a significant amount of blowby. Thus, the purge valve doesn't put a lot of junk into the manifold. After several years, a thin film of black gunk does build up, but this gunk if anything SMOOTHS out the airflow path through the manifold. Smoother path = better flow (usually). The charcoal canister doesn't introduce any junk into the manifold, only fumes. The EGR valve doesn't put any of it's output into the manifold. It directs it's flow directly to the primary intake ports in the center iron.

An RX-7 is not a Cavalier, thank god.

 

Nopistons,
Just a little clarification for you. While Michigan may not have emissions testing, Federal Law makes it illegal to remove a catalytic converter that was OEM equipment for the year model in question.

I don't have a problem with gutting emissions equipment for a track only vehicle. However, think of the consequences if others besides yourself did the same for daily drivers. If you still don't care, then you shouldn't mind if a stranger blows second hand cigarette smoke into your face either? Its the same principle.

Yes, a restrictive exhaust can cost you in power but there are legal ways around that issue. The rotary engine pollutes enough due to its oil burning nature, we don't need to make it worse.

Oh, this is one of the few auto forums that actually promotes or overlooks illegal recommendations. Many other forum moderators will shut a thread down with respect to an illegal activity/recomendation.

 

Whoa, wait a minute. Aaron I agree a lot with what you normally post but I'm gonna have to disagree here. There is no way anyone can tell me that the gunk that built up in my UIM was going to help my airflow. It just doesnt make sense. I wish I had take pictures of it before and after I had it hot tanked, cause it was nasty before. And since removing all emissions I've noticed that everytime I remove the manifold its still just as clean. I see your thought process though, but I think your calculating for a slick oil residue on the inside of a manifold, not the black cruddy **** I found in mine.
As far as gaining horsepower though, your absolutely right about the only gain being cat removal. Thats the only benefit besides a cleaner running motor. But keep in mind when I say "cleaner running" its cause I'm referring to the fact that all the junk that used to be recycled back through the motor is now going out the tail pipe, which also results in strong exhaust fumes. I get complaints from people frequently.

 

Thank god this isnt one of them.

 

My black crudy stuff had actually cured to a very slick coating. It made the casting pores almost disappear. Different cars run in different climates will of course produce other results.

My major point (and I was not very good at explaining it) was that any buildup inside the intake is going to have almost zero effect. The stock intake casting is very rough inside, so any rough buildup will be no different then the original casting. The diameter of the runners may shrink by a tiny amount, but it's going to be inconsequential since the manifolds have so much extra room to breath anyway.

Yes, removing the emissions will result in a cleaner intake manifold because the PCV is gone. But a power mod? No.

If you are really bored one day, coat the inside of your manifold with POR-15. It dries glass-smooth and will not allow any crud to stick. Poor man's ceramic coat.

 

First of all, i am a smoker so i dont really mind second hand smoke.. next who ever said this was a daily driver? I hate how people assume and make it sound much worse than it is. And i agree... thank god it isnt one of those forums.

 

Also, thank you to aaron and everyone else that replied with valuible information.

 

Aaron thats what i was thinking at first as well. The only thing i can possibly think of is removing the cat's. Anything else is at MOST weight reduction.

 

On the bright side, exhaust volume is decreased in daily driving by the lessened restriction on the enginge. And 2nd hand smoke burns my eyes and is just uncourteous. The only time exhaust burns the eyes is when you're following me too closely or I let completely off from 7000+ rpm. Catless is like burning trash, not smoking, especially not smoking indoors and purposely blowing it on somebody.

 

i agree nopistons, it seems like there's always someone who's trying to rain on your parade. as far as emissions go, how many cars today have cats? how many don't? There is only a handful of cars out there that don't have cats. I sincerly doubt that our choice of removing cats is going to destroy the ozone that much quicker. there is no "legal" way around emissions, granted there are high flow cats, but thats more restrictive than straight pipe. If your an rx owner, you don't care about emissions, you just want it to start on your way to school or work, and have a fun time getting there. witch is something you need to learn DrewD. I'm not trying to flame anyone here. by the way, i'll take nicoteen anyway i can get it.

 

if you can get away with no emissions do it, it makes it hell to work on the car, its dead weight, which means you'll accelerate faster, if you can remove your cats, your car runs that much better, and is less likely to overheat (they have a tendancy to clog, as was the case when i bought mine). It's going to be a little louder, but not too bad unless your flooring it.