just to help out, you can indeed adjust timing with a PC3 USB.
i've also done it for years.
when you promote the map to an advanced map, you are given to ingition tables, front and rear, with the same type of matrix as the fuel tables.
in these tables you can add or subtract timing from the base map in the ecm.

that being said, yes it can be done, is it as good as a PV or a TTS, hell no, but for a stage1 or a mild build, most issues can be dealt with, assuming that someone is not running some crazy combo of weird ****.
m

 

I checked with two different Power Commander sources, and you are right. No matter what the documentation says. Here's the written reply to my inquiry asking about the PCIII USB:

Jerry S. Schoenauer (Dynojet Research)

Aug 6, 2:33 PM PDT

Good Afternoon,

Thank you for your inquiry and interest in Dynojet products, all of our Harley-Davidson Power Commanders have the ability to adjust fuel and ignition, this is correct, no optional module is available or necessary, thank you.

Respectfully,
Jerry S. Schoenauer
Powersports/Dynamometer Support Technician

 

Well, I stand corrected; not every day that I learn something that I did not need to know but no I know. I still don't understand though since the PCIII USB is not a "flash" tuner and does not re-program the ECM but instead fools the ECM to make adjustments to fuel. How does the timing adjustment work? marcodarq says adjustments to the "base" map can be made but what about once a map has been loaded? Please explain; not arguing, still learning for my own edification.

 

the pc3 is a piggy back, that we all know, it intercepts the signal going to the injector, modifies it, then sends it on to the injector,,,,,
ecm=to pc3=to injector.
it also does the same with the ignition spark timing
ecm=to pc3=to igntion coil trigger
with the powercommanders for HD this is all part of the factory Style connectors and the layout internal to the pc3 unit.
to do this on most of the asians, you need the module then you hook the factory wires up to the input side of the module and the output back on the coils.
while you can not make as significant a change with the pc3, you can add timing or subtract it up to a limited amount in each cell. it is still t/p vs rpm, but in each cell in the matrix you can advance or retard timing.
marco

 

 

just a tad more history on the PC3,,,,,
it is a piggy back,,,,but it does not "Fool" the ecu in any way. it actually interecpts the signal coming out of the ecm and modifies it before sending it out to injector or coil. the older serial models did play games trying to trick the ecm, but the PC3(and Pc5) is a different animal. there is no back feeding of info into the ecm. the info path starts at the ecm and flows one way out of it. the pc3 and 5 for HD models have always had 4 channels. 2 are used for fuel injectors and 2 for ignition triggers. on the asian bikes( or others) that use 4 injectors or more, there aren't enough channels in the unit to be able to run ignition also, that is why the separate module needs to be used to gain the function. on bikes with 8 injectors, what they call a SFM, Secondary Fuel Module, gets hooked up to the PCV and allows access to them.
The Power Commander 3's and 5's have way more functions than most people ever know about, until they build something so out of the odrinary, the needs arise, multiple map memory, aux inputs, boost applications, nitrous all can be done with the PC.

About the flow of info out of the ECM. the ecm sends out it's pre-programmed fuel and ignition demands(the ECU FLASH), in each cell in a given table you are either adding fuel or subtraction fuel, or making no change from the stock base mapping. Same goes for ignition. If you change the PC3 Map, you are in no way changing the ECM's map. you are just making changes that are based on the flash in the ecu at the time. On the ignition side of things I'm pretty sure that you are limited on how much you can add or subtract, but I cant remember how much the limitaion actually is.
marco

 

 

Thanks for the explanation. That confirms what I figured was the PCIII strategy. I don't like it of course, because if the PCIII fails, you're stranded if you have a build that requires substantial adjustments to run without frying.