Discussion in 'Mechanics Garage' started by Yonan, Dec 23, 2010.
Yeah I am thinking about getting the PC III with the O2 sensor eliminators.. I hear nothing but good things...
Good points. Quicker throttle response is another. And maybe most importantly, it removes that crater like power drop before VTEC. I can't think of a modern sportbike that isn't limited in one way or another due to environmental controls. It's especially true on a 6gen VFR. I've been researching other bikes for the past year or so, and I'd change the fuel managment on every last one. Some bikes get big power gains and some don't, but they all run smoother.
I don't think I can ever go back to what it was like without my PCIII. The bike runs smoother, has more power, shifts easier and has a nice linear powerband, especially down low where the response has improved the most. VTEC doesn't hit as hard (feeling only) and it's easier to pull a wheelie. When crusing aroud town, the engine seemed to struggle at anything under 4000rpm in top gear, but now i can cruise as low as 3500 before it becomes a problem to accelerate smoothly.
I also found is that the engine seems to start with less cranks. It didn't take many cranks to get it to start in the first place, but its even easier now... especially when the motor is cold.
I noticed the lovely sweet exhaust smell that I'd previously only smell at high rpm. Someone can step in and correct me if I'm on the wrong track, but from what I've read and what I see myself, the O2 sensors (as part of OBDII) have absolutely nothing to do with performance when they try to maintain a specific A:F. All the computer wants to do is keep an A:R that produces the least amount of legally-sanctioned emissions products (which are only tested up to 4000-4500rpm, more on that in a second). It's pretty obvious that the A:F ratio for maximum power is not the same A:F for minimum emissions.
The PCIII with the O2 sensor eliminators allowing the PCIII to 'fully correct' from a simlulated baseline, and make the perfect A:F under 4500rpm and over 4500rpm (it can't do under 4500rpms without the eliminators). The stock system doesn't choose the ideal ratio (at under 4500) to make power mainly for emissions reasons, as the O2 sensor is really only there for emissions control. I would never run the PCIII without the O2 eliminators as there would be (I've heard some stories about it) a very odd behavior in the power band crossing 4500rpms (imagine a mini-vtec feeling right before the real vtec).
Other perks include easier shifting using the accelerator pump feature. It takes a little while to find a setting that works with the way you ride, but it sure is nice to shift more smoothly without using a clutch.
For the best performance, I found that you need to update all the firmware in the PCIII to the latest version. You also need to make sure you have the latest software on your PC along with extra enablers like the accelerator pump feature. You'll also want to run the software while the bike is on (but engine not running) to properly calibrate your throttle zero and WOT and/or whatever other sensors your PCIII setup is monitoring. Initially it is fine to just choose a premade map that is the closest match for your bike setup (ie: for a bike with slip ons, K&N do not choose a map for stock exhaust and stock filter). Your not going to blow an engine by going a tad bit lean here and there. Ideally a proper wide-band dyno tune will give you the best results, but I think you'd be hard pressed to gain more than 5% performance over a "best-fit map" unless you are running a supercharger, or some other extreme tuning/built engine (ie: block ported out with a 4" drill press or straight pipes).
BTW, PCIII software works in Linux under vbox (I run it under Arch64). I'm trying to get it to work natively through wine, but that's another story altogether...
+1 on that
With, or without, the worthless PAIR Mod?
Has anyone tried the newer Power Commander where you plug in an O2 sensor and the thing does a "custom" map itself, eliminating the need for a dyno run? Too late for me as I have the earlier version, but wondering.
My understanding is that a PCV with the auto-tune option cost more than a PCIII with a dyno tune, and still requires manual calibrations. Calibrations that, if you're like me, will get fucked. Then the machine will end up at a tuners anyway.
question; if you do a PCIII with O2 eliminators, do you get automatic adjustments for altitude or are you setting a fixed mixture until you change it yourself?
^^^ I did have this conversation with my tuner, a long time ago. I want to say that nothing more has to be done at altitude, or else I would have done it. Something about the PCIII figuring the fuel air ratio's while the ECU, even with o2 eliminators, would determine how much external oxygen was available. I'm sure the boys at Faster could give a more detailed answer regarding altitude performance. Even if there are minor adjustments that can be made to achieve a perfect map, I'm not sure it would benefit anyone in Colorado; not when we deal with altitude fluctuations of 6,000-10,000ft on a per ride basis.
Consulted Google machine. Appears popular opinion is that MAP sensor is what accounts for altitude and the O2 sensors are more of a double check on the system that it's doing what the computer thinks it's supposed to.
Well, after reading all the post here,some of you have a lot more experience with the pcIII. But this is what I noticed after a couple of good rides.
Stated earlier, bike has two brothers slip on and K&N fltr. I'm using the high mount two brothers slip on with stock or K&N fltr map from DynoJEt.
Bike runs great, but mileage has dropped significantly as expected. getting around 33mpg. Results are askew because I was constanly at WOT.
Today I am going to try the map for a stock bike and see how she runs.
5% on a 100 HP machine is 5 HP, that is a lot to just throw away by using a best fit map. Considering how expensive horsepower is, I would say 5 HP for around $300.00 is a pretty damn good deal.
Back from my mpg test ride. Did 131 miles averaged 41mpg running the map that came with the pc3, vs 33 mpg running map for my pipe and fltr. Did not notice much if any power difference, I'm sure there was one but for the street I prefer the mileage. Bike ran great never hiccuped, surged or did anything funny. Probally do a couple more comparison rides just to get a better average. Getting rid of the surge at 5600-rpm defiantly makes for better riding.:smile:
Yonan, check your PMs...
Separate names with a comma.