I was Wondering - if the black soot in the exhaust, which is normal for the rx-8, is due to unburnt gas and the air/furl ratio; then if it were to original spec (250 hp) before the revision, would it not dirty the exhaust.

i heard they made the air/fuel ratio richer to meet the emissions laws.

just a thought

 

you would still have it, as the car burns oil as it runs.

 

Wiping the soot off my exhaust pipes has become a morning ritual.

 

The car does run richer, but in the high rpms. My car stock was doing 11 AFR at 6,000 rpm and upwards.

 

How do we clean the soot we see out then? Just a paper towel on a cooled exhaust? Wheel cleaner? Chrome polish?

 

I use chrome polish. But if you keep it clean on a regular basis, you can wipe it with a paper towel too.

 

I thought running richer would increase pollution, not lower it.

 

You are right Rob. Increasing the fuel to rich would increase pollution. The EPA folks don't care much until a vehicle exceeds the Fed requirememts so a vehicle that beats EPA they don't care. Have no clue of the rotarys and have not done any research but the engine is not a gas mizer and it runs on 91 Octane so the design and the fact that it throws oil into the intake to lube some moving parts is part of the soot issue in the exhaust. All cars get some sort of junk around the tail pipe. I guess cleaning it frequently is all we can do with the condition.

 

Thanks again Jason. Liked the mirror video!!! Sound and all.

 

Actually, they made it richer to lower the exhaust temperature to satisfy a *future* California requirement for catalytic converter longevity.

Pretty ridiculous, huh?

 

I have a great brush I use on my rims / tires, and when I'm done doing that I stick the brush in my tailpipe and swirl it around a few times. No more black soot!

-Rupes

 

I thought it was a new EPA requirement of Cat life. I don't think they would have gone thru the 250/238hp SNAFU to satisfy a reg that didn't exist yet.

 

Simple Green on a rag... wipe and drive away!

 

running the car rich or lean is a way of controlling catalytic temperature which is very import for emissions. If the surface of the catalytic converter isn't the right temperature, the exhaust gases and air will not react on its surface and cause bad emissions.

 

I spayed a small bit of wheel cleaner on the pipe ends and hosed it off and they wiped dry. It looks new again. This was on cool pipes. The soot is a known fact so we just have to keep the tips clean regularly.

 

I use wheel cleaner on my tips as well. Been doing that for about 7 years with the FD. and the PFS exhaust. Works fairly well, but you have to keep up with it and do it every time you wash the car. Otherwise you have to use polish.

 

I haven't cleaned my RX-8 tips yet, but I used to use Never-Dull on the racing beat exhaust on my FD. Worked great even when it was really dirty.

 

i think the soot looks nice especially with my gold racing beat tips...