O2 Sensors and Race Gas

[theshadowrider]

I have a question for all you turbo dragon guys. I have a 2008 dragon 800 and I am looking to turbo it. From what I have read some guys like to use the A/F ratio gauge to help tuning instead of an egt. But I was told they don't last very long (aprox. 600 mile) because of the race gas. I am assuming that is because it has lead in it. So do you have to replace the O2 sensor for the efi also? Do they go bad? When they go bad what happens, do you burn up our motor? Seem like if a a/f ratio gauge goes out why wouldn't the o2 sensor, aren't they the same thing?

Next question. Why doesn't someone make a gauge that just piggy backs the stock o2 senor and make a display of what the stock one is doing for the efi?

Thanks

 

[Kestrel2126]

I think you have a little bit of your info mixed up. First, I don't believe the Polaris has a stock O2 sensor. I think you are talking about the sensor that screws into the middle of the expansion chamber (pipe). This is actually a stock EGT probe that is linked to the ECU to add fuel in emergency situations so you don't burn down, a fail safe if you will. You can't actually view any data from this probe, it goes directly to the computer.
Second, O2 snesors don't hold up well on 2-strokes regardless of whether you run race gas or not. It is the oil that will plug them up and cause them to fail (race gas probably won't do it any favors due to the lead). A lot of guys run them only when tuning, and then pull them and replace with a plug when actually riding.
Also I think the Air Fuel guage and O2 sensors you speak of are actually essentially 1 and the same. If you are running an O2 sensor, you then read the data on a Air/Fuel guage. It would be like having EGT probes, and no Digatron, Koso, Racepak, etc.
I hope this helps, good luck

 

[theshadowrider]

So you are saying that the senor/probe located in the middle of the pipe is a egt and only used for emergency situations? How does the efi tune/adjust the engine then? I thought the dragon had a closed loop system running an o2 sensor?

 

[Vertical Asshauler]

Dragon doesn't have an O2 sensor only the exhaust probe in the center of the pipe. It measures temperature not an air/fuel ratio.

 

[mountainhorse]

So you are saying that the senor/probe located in the middle of the pipe is a egt and only used for emergency situations? How does the efi tune/adjust the engine then? I thought the dragon had a closed loop system running an o2 sensor?

Nope...

It runs an open loop, speed/density setup with TPS, Det, coolant temp, air temp, and exhaust temp inputs plus a built in Baro pressure sensor in the ECU itself.

 

[theshadowrider]

Makes a lot more sense

This makes sense. I thought the O2 sensor makes the adjustments but couldn't figure out how the o2 don't go bad with the oil and leaded fuel. Where on the sled is the outside temp sensor, and pressure located?

 

[snow_knight]

run a heat sink bung for your bosch sensor on the afr gauge, have 3k miles on the same sensor running everything from 100ll to 117 vp fuel with it. Have checked it with my spare sensor couple times a season. still running strong

 

[POLARIS600cc]

run a heat sink bung for your bosch sensor on the afr gauge, have 3k miles on the same sensor running everything from 100ll to 117 vp fuel with it. Have checked it with my spare sensor couple times a season. still running strong

Can you post a link to someplace to get this bung you use please?

 

[snow_knight]

Can you post a link to someplace to get this bung you use please?

JEGS

I got mine from local store cheaper than i could find online.

 

[whittaker727]

run a heat sink bung for your bosch sensor on the afr gauge, have 3k miles on the same sensor running everything from 100ll to 117 vp fuel with it. Have checked it with my spare sensor couple times a season. still running strong

Does this run a gauge? Do you have any pics of this?

 

[chrisco]

3000 MILES ON MINE 08 D8 TURBO NO PROBLEMS. JUST USE WHAT COMES WITH THE KIT (AEM GAUGE)