Custom/Hybrid EGT, h20, 02 sensors -- Anyone every thought to install these?

JGringo

When in doubt, Throttle-out.
Hey X-members,

I was just wondering if anyone has ever looked into installing EGT, water temp, or 02 sensors to their ski before? I have been looking around for solutions to avoiding detonation with my ski's engine, as well as improving my ability to fine tune my carburetors...

I have been looking into snowmobile EGT sensory systems like Digatron, Innovate, and KOSO for adequate PWC applications. Does anyone else have experience with this? Would this be overkill or a knowledgeable investment/idea??

Some of these systems can read EGT, 02, and Water temp values all at once. This would clearly help the user prevent engine failure, however, installation of the sensors would be a hell of a task...


:scratchchin: ___Thoughts?

-Gringo
 

Attachments

  • EGT Sensor Gauges.jpg
    EGT Sensor Gauges.jpg
    42.6 KB · Views: 51
  • KOSO Dual Gauge.jpg
    KOSO Dual Gauge.jpg
    11.7 KB · Views: 54
  • Ski Doo EGT Sensor Installed.jpg
    Ski Doo EGT Sensor Installed.jpg
    45.7 KB · Views: 62
  • innovate_replacement_o2_wideband_sensor.jpg
    innovate_replacement_o2_wideband_sensor.jpg
    117.2 KB · Views: 49
  • EGT_sensor_thermocouple.jpg
    EGT_sensor_thermocouple.jpg
    72.6 KB · Views: 53
Last edited:
The oil in the 2 stroke exhaust would destroy an o2 sensor within a day. The EGT probes would work. I want the koso unit for my sled. I am just not 100% that it is waterproof.
 
There is a EGT set- up out there that some watercraft racers use. It is the Racepak Hot Tach set-up. You wouldn't want to use a Koso or Digitron set-up because I don't think either set-up is going to be completely waterproof. I don't think either one was designed to be submerged.

As far as running a O2 sensor, the sensor will work for a while but it will burn out because of the oil. Dynojet uses a O2 set-up with their Autotune but it is designed to be removed once you are done tuning so you don't burn up $100 sensors. And a lot of watercraft exhausts have water injected before the stinger that will probably causes problems with the sensor depending on the placement of the O2 sensor.

And the Arctic Cat M1000 doesn't come from the factory with a O2 sensor. The sensor in the expansion chamber monitors pipe temperature.
 
I think you would have to run a dry pipe to use an O2 sensor, since the water from a wet pipe would corrupt the data or destroy the sensor. The Oil is still an issue. You can use an O2 sensor for a certain number of hours in a dry two stroke exhaust, like a motorcycle, sled, or quad, but from what I've read, guys only use them for tuning, and then remove them. This is probably why you don't see any closed loop efi systems on two strokes.

EGT is a good idea, but who has data for watercraft engines? Placement of the EGT sensor is critical, otherwise it's just an arbitrary temperature reading, unless you plan to melt a piston just to see what temp is safe vs. unsafe. Also, for EGT, doesn't detonation equal a lower temperature? Would the EGT be affected by water injection, like the top screw of a B-pipe?
 

OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
I ran a Hottach III in a sitdown I built up but could never tune. After 5 topends in a season I invested in the hottach and was able to map out my powerband with the 2 egt's and and rpm sensor. Ended up being a bad port job that didn't match the pipe I was running and a total waste of time and money. It was an interesting experiment to say the least but totally unnecessary in 99.9% of scenarios.

It basically just confirmed what I already suspected and any decent engine builder would have already known.
 
Last edited:

JGringo

When in doubt, Throttle-out.
I ran a Hottach III in a sitdown I built up but could never tune. After 5 topends in a season I invested in the hottach and was able to map out my powerband with the 2 egt's and and rpm sensor. Ended up being a bad port job that didn't match the pipe I was running and a total waste of time and money. It was an interesting experiment to say the least but totally unnecessary in 99.9% of scenarios.

It basically just confirmed what I already suspected and any decent engine builder would have already known.

Soo... essentially you are claiming that when the engine is properly ported/set-up -- all of these sensors are a waste? I am not a 'pro' engine builder/tuner but you feel these wouldn't be benefitial even so?
 

OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
IMO, If you were looking to run on the ragged edge or tune in some radical new setup then it might be worthwhile, otherwise it's purely academic.

I will say that what I learned from that experience gave me a much better understanding about tuning that I would not have learned otherwise.
 
Top Bottom