Good wideband location?
 

Im about ready to finally have the exhaust finished up and installed onto my twin t04e turbo setup. Its a full twin exhaust setup, one pipe from each turbo, dual inlet/dual outlet muffler. Im wondering if anyone can give me some information as to what to do about a wideband. Im looking at (2) options. First is a single wideband either in one pipe, leaving the other pipe without a wideband, or would a h pipe type design where I have the dual exhaust have one crossover pipe and mount the sensor there (not sure if that would give an accurate reading for both) The second option is to have a dual wideband setup like those from FJO which cost in the neighborhood of $800. Just wondering what advice is out there.

How about an x pipe so you can get a good mix from both pipes.

To be honest I have no clue, but on another note are you saying that you are going to have 2 seperate pipes not connected in anyway (1 for each turbo) coming out the back? if so please post up some vids of how it sounds like, I thought about doing the same thing if I were to go with twins and I was wondering how it would sound. good luck man! I give you mad props.

The best cost more. The best job as far as tuning goes is to have a sensor in each pipe . The rotors do not mix and fire with the same air /fuel ratio . With one unit between two pipes you get a mixed reading . One chamber can be running rich when the other is lean . Your reading will be incorrect .If you are going to spend the time and money to do this fine job, finish it the best you can . Do not let someone say you can not adjust them seperately so it does not matter .

anyone else?

look around for people running twin setups maybe on supra forums because you're one of the few that is running twins

The best option would be dual sensors. However since it is really difficult to tune the engine per rotor, you are better off bringing the two downpipes together into a Y, and putting the WBo2 sensor after they come together. This should also give more life to the sensor. Being further downstream should not be a problem.

I will be installing my WBo2 sensor in the Metallit catalytic before the core. People have shown that there is not a significant difference in readings from this location versus further upstream. Benefit is that you are less likely to overheat the sensor, and you only put one in.

Remember, too, that WBo2 sensors must always remain heated during engine operation or the sensors will fail within minutes. Therefore, a completely separated exhaust system will require either two sets of single-sensor WBo2 electronics, or a sophisticated multi-sensor design.

In some racing situations this might well be ideal, justified, and maybe even mandatory for ultimate performance, but for the street I'm not sure you'll really gain that much. Consider that a rotary will at best have 3 combustion chambers being controlled by one sensor/injector(s) system so you're still only getting an averaged reading.

FDjunkie states you have three combustion chambers , do you have a three rotor motor .Wow with that expence you should not care about the extra for two sensors .

its a two rotor

guess thats all the advice, I figured with all the tech people on here, id have a better response

Better response or the response you wanted to hear which validated your idea?

Unless you plan on tuning each rotor seperately, it's a waste of money. If you are running a PowerFC, then I don't think it's possible. I don't know if a Haltech does this or not. And why do you need to have seperate exhausts for each turbo instead of collecting to a larger exhaust pipe and reading the data.

i agree its a waste of money to get seperate sensors since you cant adjust between the two. maybe install a bung in each pipe and while testing move the sensor from one to the other while plugging to check inconsistencys. after that a sensor in one pipe should give you what you need.

If you really think you need to spend money to make sure both rotors are doing the same thing i would reccomend two egt probes. It would be alot cheaper then two widebands and give you the same information.

well the reason for the completely seperate exhausts was a matter of cost, ended up being cheaper to go this route then run into a large single back, I just wasnt sure which would be the better the way to go. I know that the rear rotor tends to run leaner and wanted to make sure that extra fuel is applied to that instead of just having an average of the two rotors combined. I dont mind paying the extra money for the dual setup but if I dont need it and running one sensor on a y pipe would do the trick then im all for it.

does anyone have any idea which sensor the fjo unit uses (in other words a part number)

anyone?

I'll second the person who suggested running one wide band after a collector and then use two EGT's, one in each header, to make sure front and rear are approximately the same temp. This is what I'm converting to over the next month. I was trying to just use a wideband before but I was getting odd results based on feel so I'll use the EGT's to confirm the wideband numbers as well as assist with timing issues. I'm a bit confused about how it could have been cheaper to do two tubes all the way back instead of collecting and running one back? Have any pictures of the setup?

Kevin

I would suggest getting the dual wbo2 setup, one for each pipe. If that's to expensive or too hard to tune then, I would go with the idea of combining the two dp's in to one. BTW, you should post some pics, sounds like a great setup. props

Kevin, I was hoping you would chime in, Ill have pictures in a week or so, once Im finished with the mechanical end of things. I got a deal on the fjo dual setup and figured it couldnt hurt, but I needed to order sensors as fjo wants almost $180 a sensor, I intend on doing twin egt's as well.

Sure can't hurt to run two of each. Looking forward to your pictures sounds pretty neat.

Kevin T. Wyum

definitely post pics...sounds very cool

Like I said, pics in about a week