Opinions, please:

Would adding a cat to a street ported 12a w/ a Hollley that is pre mixed, clean the exhaust

 

A good high flow cat, along with an air pump, should clean the emmissions up to a tolerable level. A rich A/F mix will shorten the life of a cat, and make it get much hotter. The premix can lead to the cat getting clogged, but the rich A/F would do it in faster.
2 stroke oil will actually be a little freindlier to the cat vs oil from the oilpan, but the heavier mix ratio will override that.
Under these conditions, a cat would likely last about 2 years, before it started degrading enough to affect the performance of your car.

 

Is the air pump a must? Or does it just clean better with it?

 

Most cats will need an air pump, or they will not work very well, nor live very long.
The air pump just supplies fresh air to the cat, so it can burn off the unburned fuel. Hard to do it's job, without the proper tools.

 

Most piston engines,(especially lean running EFI piston engines) leave enough oxygen in the exhaust for the cats to function correctly.
The rotary design leaves almost no oxygen in the exhaust,thus it requires the smog pump,there is no getting around it.Plus,the high amounts of wasted fuel means the cat is worked very hard to keep things clean.That is the main reason for the rotaries hot exhaust and its ability to kill cheapo catylists.
Simply running the smogpump full time into the cat, might be OK for a short while(like getting past a smog test).....but for the cat to survive long and not overheat,the stock ECU and ACV need to be intact and working,to regulate and route the smogpump air to the correct location under the correct conditions.

 

So basically for "cleaner" exhaust I would have to replace the cat yearly and with out the air pump it wouldnt be much cleaner exhaust?

Im not trying to pass smog, just want my girl to ride in my rexy every once in a while.

 

Your just throwing money away buying a cat,(even just one cat)... if the rest of the smog system isnt hooked up and working.It wont be clean enough to not stink,the environment wont be any better off,youll just have less money.Not to mention the fire hazards of clogging and potentially melting down the cat.

If she doesnt like the smell,spend your money on new tailight and rear hatch gaskets.Then put some turndown exhaust tips on the muffler,like the Aussies do.
If she doesnt like non-enviromentally cars.....well then your screwed no matter what you do, or dont do.......rotaries arent green!

 

Cat? what cat?

Ha, ha ! !

This is what I figured, I just figured I would bring it up and see what thoughts are out there.

 

Does adding a turbo reduce the fumes any by cooling the exhaust? I have heard before tha NA SP is the worst smelling, fire breathing bastards!

 

No.

Cooling?.....with a turbo?......

No.

All rotaries smell,and they all can breathe flames.....just depends on your mods and exhaust lay out.
The gratuitous pollution is a result of their internal design,it cant be done away with, without using a well designed and complete pollution scrubbing system......cat,airpump,thermal reactor,ACV,rats nest,ECU,ect,ect,ect....

 

Uh, yea, I would think the exhaust going through a turbine would be cooler at the tip of the muffler than straight out of the combustion chamber and only through a muffler.

I have just always heard that a NA SP is the worst smelling exhaust around.