Ok, some of you may have seen some of my posts with my ongoing inspection hurdles, and im sure many of you have had similar times of the year.. its all part of having an rx7, a modified one at that.

My 91 has a JDM swapped TII motor with little to none emissions equipment. I have an ACV but the only thing hooked up to it is the vacuum line going to the T that splits the BOV and BPS. I tried to replicate the factor air pump setup, purchased an airpump and it would not fit due to my custom intercooler piping and intake pipe.

I tried to inspect with no air pump and wow, what ugly number i received the people practically laughed in my face. So the next step was the LT1 electric air pump.. i put that on as i have read and pumped the air directly into the aftermarket Bonez cat.
Wow, what an amazing difference most of the tests passed with flying colors!!!!

The only setback was my low speed HC failed by 40 points. So i went and put some Iso-Heet de-moisturizer in the fuel, then ran a good bit to get the motor hot. I went back and everything was EVEN LOWER!!! except the low speed hydrocarbons now failed by almost 90 points. So whats next??? It's so close i hate to spend a lot of money on anything extreme.

I called Rotary Performance for some direction and they told me the airpump should be setup to pump air into the ACV instead of the Cat so my thought is this:
Should I put a T at the electric airpump and split the air between the ACV and air pump? If i do that where do i need to hook the other vacuum lines?

I know I have written a novel, and for that i apologise but my inspection is 7 months out and i really need to get this settled ASAP!!!


Thank you for all your help guys

 

I had the same problem with HC's, as most rotaries will. I had an advantage though running a standalone ECU. I locked my timing at -5 degrees and passed on my 5th try
The key for me for those last few points was to lower the timing.
You can lower your timing by turning the CAS if you are running the stock ECU.

 

CAS? What is that and how do i adjust it? How much to adjust?

 

CAS = Crank Angle Sensor.
this thing:

Before you move it, MARK IT how it sits (held in place with a 10MM nut). Don't go with this picture though, you aren't pulling it out, just adjusting it. Turning to the "left" lowers it. Like you are taking a lid off a jar. Timing drops, as does power. When you are done, be sure to put it back the way it was or performance will suffer.

 

Ok, thats some good information, should i adjust it while the car is idling? or while shutoff? how much is a safe amount to turn it to the left? is there any risk of detonation involved with this?

Thanks for all your help through this process beefhole!

 

You might want to investigate the possibility of registering your car as a classic. Not sure about TX, but in PA, the 2nd gen qualifies and there is no emission testing required for classic-registered cars.

 

in texas 25 years old = classic

 

Well the alcohol seems like a pain to drain my full tank of fuel so I'm gonna try injecting air into the acv as well as the cat and see what that does...

 

The CAS can be moved when running or not. You don't have to drain the tank, just go driving for a while and run the fuel down so you can dump alcohol in it.

 

only 3 more years till mine is "classic" lol.

 

Too bad. PA is 15 yrs for classic, 25 years for antique.

 

well, since it was so close i went back without really doing anything, hoping by a miracle it would run a little better and i'd get by but everything was WORSE! this time my high speed HC failed by 70 points and my low speed HC failed by 130 points!

I got 15 days till my reinspection and im gonna split the air from the LT1 airpump into the ACV and Cat as well as put about 2 gallons of alcohol into half a tank of gas and hope that does it! If not look for my For Sale ad

 

Ok, i don't have time to run down the fuel, and im concerned as to why my HCs are going up, is it possible that the cat is being burned up while using the electric air pump on the test?

Can i put 3 gallons of the denatured alcohol in the tank with my 3/4 tank of gas and achieve positive results? or does it need to be less then 1/4 a tank?

 

What other mods do you have? Need a little more info...
You running a standalone? Pull her a little leaner and drop boost a little.

High HydroCarbons indicates you're running rich as ****.

Have you tried the typical plugs, wires, fuel and air filters tuneup yet? (And what did your old plugs look like?)

And how old is that Bonez Cat?

 

its a stock JDM 13bt swapped into a 91 N/A. Everything is stock except for FMIC, 3" exhaust and custom intake and FCD. Everything else is completely stock. The bonez cat is new. i purchased it for inspection purposes and has only been used back and forth from inspection station and around town preparing for inspections... Initially i did an oil change and spark plugs, the wires were unavailable at the parts store at the time and seemed to be in pretty good shape.
The air filter is an open cone style filter i guess it could be cleaned?

The ACV is there but there is nothing hooked up to it except one vacuum line going to the BPS

I guess im gonna dump some denatured alcohol in the tank this week and try again, what else can i do to lower hydrocarbons? i looked into adjusting the CAS but i don't have a timing light and i'm not sure i wanna mess with that...

 

Make sure that cat is well up to temperature when you hit the inspection station. Take her on the open road for a good thrashing.

You sure your electric air pump is putting enough air into the catalytic too? Needs oxygen to burn off the unburned fuel. (That's what Hydrocarbons are... Raw fuel.)

 

OK guys, i've all but given up here. everytime i go back to the inspection station my results are getting worse with everything i try. I put the electric air pump on and i was only off by 40HC on lowspeed i got so excited, and its gotten worse everytime i go back. Today i went with 1.25 gallons of alcohol mixed with 1/4 of a tank and still no pass!

what other options do i have? Should i go for a Power FC with a good tune?

at this point im seriously considering selling.

 

in the STOCK setup the air pump air goes from the air pump to the ACV to the EXHAUST PORTS.

when you take the acv off there is a round port in the intake, THAT is where the air goes.

the pipe to the cat is for something else

 

Maybe i need to set it up to stock type setup, has anyone done this with the electric airpump?