[Sierra]

So,

I'm about to pull the trigger on the PC5, but have a question. The input side of the PC5 is the TPS, Crank Position Sensor, Spark timing (which it's modifying, in reference to the CPS), and Pulse Width on the Injector (which it's modifying on the firing of the Injector) nothing on the PC5 to determine altitude from the ECU.

On the Wolvy there is a Intake Air Pressure Sensor input on the ECU, as well as Intake Air Temp (No Barometric Sensor which is necessary for determining Altitude). According to the Service Manual it determines the Altitude, but I believe this is ONLY at startup before the engine cranks, then the ECU uses this for the Intake Pressure, which is NO longer Altitude Pressure. And when riding, in 20 minutes I can go from 5000' to 8500'.

Those of us who ride between 4500-8000 ft (I live at 5000 and ride mostly above this altitude), O2 is not nearly what it is at sea level. The PC5 becomes completely useless and real quick under all circumstances, which is kinda hard to swallow for $319.00. Since the PC5 doesn't know the altitude or the Injector pulse width due to altitude, it's making a real huge assumption on the modified pulse width it's sending to the spark and injector!
Sea Level - 100% O2
1000m (3281') - 88% O2
2500m (8500') - 73% O2

WHAT I'M TRYING TO GET TO WITH ALL THIS...

If the Air Pressure Sensor on the Wolvy is not calculating a true Altitude all the time then the EFI will be off once you get moving, and no PC5 map will fix this. The only way to have an optimum, or even close to optimum ratio is to use a Lambda sensor (Wide Band O2 Sensor). And that means throwing another ton of money at this whole problem, which is why I'm a firm believer in Lambda sensors from the factory.

And, if I'm thinking this through correctly (I may not be... but it makes a ton of sense to me), even if the wolverine ECU is making the necessary changes to the injector's pulse width, the PC5 doesn't know why it's doing it, and is just making some wild guesses. So, if I tuned it to about 13.5 on the ground, I don't see how it stays there once up in the mountains.

Will I buy the PC5, yes only because the current AF ratio from stock absolutely is way too lean and it's the only way to fix it (no one does ECU flashes), that doesn't mean I'm going to be happy about it. Any help on either correcting me or getting to answering this will be great.

Thanks-

 

[Hunterworks]

The PCV does not care about what the ECU is doing, when a MAP is installed it simply adds the fuel it was programmed in to what the ECU does.

Example: If we determined the fuel mixture was 10% too lean at sea level and let the PCV add the 10% fuel to fix it then at 10,000 ft the ECU and those two sensors will cut fuel because of altitude and the PCV would still be giving the 10% because even at that altitude the ECU would still be 10% too lean even after adjustment. If it is too lean at sea level it would be too lean at 10,000 ft too.

Very hard to explain in text but it works

Two ways to fix this, turn the engine off every couple 1000 ft or buy a auto tuner for the PCV

BTW, the Power Commander V is $340 with our maps and rev extend codes already in it.

You quoted $319 that might the fuel only controller not the ignition/fuel controller

Here is a link to it.

Link to - Wolverine PCV w/ignition

Thanks,
Todd

 

[TINKEN]

Air/fuel mixtures become richer as altitude increases. The pcv has the ability to run two maps that are shift on the fly, meaning that they can be changed while driving. You can add a slightly leaner map to your #2 map to trigger at 10,000 feet or where ever you choose.

Also when tuning your cvt sheave, you will need to run lighter weights to compensate for power loss at high altitude. The pcv will help with this too by raising the rev limiter.

 

[R2V2]

Would the Dobeck AFR+ Gen 4 be an option for different altitudes? The physics of pv = nRt shows the impact of barometric pressure or Oxygen on performance. Oxygen % and altitude sure impact my breathing during elk hunting in Idaho. They also impact internal combustion engines and fuel ratios. Todd, you could map anticipated altitudes into the PCV, right? 3000' mode and 8000' mode or other?

 

[Hunterworks]

Yes the dobeck would but again the stock sensor will do it, just turn it off and back on. The dobeck is a problematic controller which is why we had to stop selling them. I actually threw three brand new ones in the garbage two weeks ago for a RZR

It also can't do ignition or control rev limiters

I think I would prefer the turn off and back on method because if you did the wide band and it was making corrections in the back ground when you turned engine off and back on for whatever and it corrected itself then the wide band would have to make a sudden large change and might run bad for a bit.

The PC5 has inputs, if you really wanted to go to the trouble of doing you could wire one of those sensors into it and tell it what to do with certain values. I have never used that function of it but you can and of course you can just buy the auto-tuner for it and have wideband

None of this has a been a issue for anyone that I know of so just let the stock system do it's job

Todd

 

[R2V2]

Great info. Thanks Todd for your helpful insights. I will be ordering a PCV in the future from you.

 

[TINKEN]

The Doebeck controller does not even compare. The pc5 is a mini computer with software. The capabilities of the pc5 are extensive.

 

[Yamahopper]

I worked many years as an automotive mechanic and when I read this post I was surprised. Doesn't Yamaha use the the reading of the map sensor at WOT to calculate atmospheric pressure and be able to adjust on the go for elevation?
Also read a post about reflashing the ECM by Alba racing and switch the program to read sensor input other than RPM to determine fuel mixtures and timing are these systems really that far behind the automotive industry standards?

 

[Hunterworks]

I worked many years as an automotive mechanic and when I read this post I was surprised. Doesn't Yamaha use the the reading of the map sensor at WOT to calculate atmospheric pressure and be able to adjust on the go for elevation?
Also read a post about reflashing the ECM by Alba racing and switch the program to read sensor input other than RPM to determine fuel mixtures and timing are these systems really that far behind the automotive industry standards?

This vehicle fuel map is extremely lean for EPA reasons and I don't understand the need to have to make you turn it off and back up for the sensor to take care of elevation but that is how they did it.