I have a 95" TC with mild headwork and 48mm throttle body. I currently use the Direct Link tuner, but only tuner I trust nearby that works with it is 6 hr drive away. I just installed new Fatcat 2-1 exhaust and want to get it tuned in correctly coming from short 2-2 Pro-Streets. Here is question:
I have seen a few PC maps that might be close enough to get the bike to a Tuning Link, but do the PCIII canned maps make incremental adjustments to fuel based on stock map, or do they completely override map currently in ECU? What I am really trying to understand is Direct Link tuner I have has been tuned for my setup before the exhaust swap - canned maps I see for similar engine builds are for stock or stage 1 ECU map. If I load a map off PC database with similar engine build as mine but for a stock ECU, will the fuel delivery changes be based on some % increase of stock rate at a given RPM, or is the PC programmed to deliver a set amount of fuel regardless of what the ECU is programmed for?
My question is clear in my mind, but sorry if I am not putting into words very well. Just put pipes on and have not a chance to ride, but starting it and letting it idle, it seems to be running kind of rough. Don't want to damage anything riding it the 60 - 70 miles to a tuning link center.

 

A Power Commander is a "piggy back" tuner. It over rides the ECU but there are canned maps that take into consideration the information the ECU has in it. For example, if you have X components on you bike and your bike has a stage 1 download in it, the canned map would say X parts and stage 1 download. If it did not have a download it might say something like slip on pipes, and Screamin Eagle AC and stock ECU kind thing. Does that make sense? I personally have seen some of the canned maps work ok and others WAY off. I own a dyno however and IMO nothing compares to a good dyno tune regardless of what your compnents are. Does this help?

 

Maybe this will help you understand it. It's a bit more involved but this should clear it up a bit for you. The PC maps are run 'on top' of the stock ECU maps. Meaning that nothing is changed in your stock ECU.

The PCIII connects between the ECU and the injectors, the injectors are no longer under the control of the ECU but instead are driven from the PCIII, The PCIII also connects to the throttle position wire from the throttle position sensor to the ECU.

When the ECU attempts to open the injector it does not open the injector, instead this signal is picked up by the PCIII and it opens the corresponding injector. The amount is controlled by the map that is loaded in the PCIII.

When the ECU closes the injector the PCIII will record the time that the injector was open and apply a plus or minus trim.

The amount of trim applied by the PCIII is determined by looking up the PCIII trim map.

The PCIII trim map is divided into 500 RPM increments and has nine throttle increments (0,2,5,10,20,40,60,80,100).

The maps that are available on the Dyno Jet website. These maps will get your bike close, but to get the most out of your bike (and the $$ you spent on the PCIII) you really should have a good dyno tune done on it. As an example, when I installed the PCIII on my bike it ran much better but had a bit of deceleration 'pop' and the gas mileage went down. I took it to a dyno shop and got back a bike that ran even better, with no decel 'pop' and it got better mileage than it did when it was stock.

 

Thanks for the info. I am familiar with the PC - had one in past when I just had intake, exhaust and cams - bike ran great. Installed the Direct Link after big bore kit, etc. to get rid of the piggy back device. I was not sure if Iinstalled a canned PC map on bike with a stock ECU or same bike with a flashed map ECU, would bike run the same in both situations regardless of ECU map settings if the canned PC map is the same?

Definitely planned on getting it tuned - just tired of driving 6 hours to get it tuned and paying $400 a tune. PC gives me more local options and cost less since the guy I want to use has DynoJet Tuning Link software which I believ cuts down time to tune. If I could get bike to ride like it did with just the intake, exhaust and cams, and add some power for the big bore, head and TB, I would be happy.

 

I think I understand what you're saying. My ECU was 'flashed' by the dealer with the Stage 1 flash. The PCIII works just fine over that. I would think yours would be the same, as the PC goes between the ECU and the injectors. It would still read the signal coming from the ECU and make the necessary changes.

 

Don't waste your time with the PCIII as you already have a better setup with the tuning link.
I would guess you had Ed tune it and he is one of the best in the business. http://www.thedynodifference.com/ No reason to start changing things up with an inferior tuner like the PCIII when you already own something better, 6 hrs is nothing for the life of your bike.

 

Now that I went back and read my explanation, it sucked! Much better explanation by others and I agree 100% with Bob as well. The tuner you have is better IMO.

 

Have no problem with Direct Link other than 6 hour ride each way, missing a day from work and $400/tune. I have had it tuned three times this year because of mods and am getting tired of spending the money - miss my old carbed bike. My bike started and ran great with the PCIII before with jut a canned map and I have no reason to believe it won't do so now with a tuned map using the Tuning Link software. Plus, I'll still have the Direct Link - any issues, I can sell the PCIII and make the trip back to Dallas, but I like a little flexibility if I make a minor change.