Hey guys this is my first post on here . I have a 2010 FXDC with a PC5 , HD stage one AC , and V&H Staight Shot slipons (unbaffled). I have been gathering parts to change the heads and cams . I have a local shop that can help me with a dyno tune . My question is do yall think I should use the Autotune along with the PC5 ?

I was riding 2 up the other day and the bike was a pig with the hot humid Texas weather . So I started thinking I might should wait to change it up till I get the Autotune so the AF ratio will stay in check .

Im an old Drag Racer with plenty of mechanical know how but I dont have much experience with Harleys and electronic fuel injection .

And I know (no pic no bike) lol

Any help would be apreciated .

 

I think an autotune of some sort is ideal. But if you can get a Dyno tune cheap enough once all of your items are installed, that would suffice.

I think Power Commander's Autotune is a bit different than the Thundermax variety. Someone can correct me if I'm wrong here but I think Thudnermax Autotune stays on the bike forever, whereas PC5's Autotune is meant to be removed after so long once the PC5 is "trained". I remember reading this but I could be wrong.

 

There is soo much material here on pc5 and auto tunes. It'll take a few hours to sift through it all. In the end. Your wallet will dictate your decision.
I have a pc.5 and side shots on my ride, I suggest tuning it after your cam work is complete . Waste of time and most importantly money to dyno you ride twice..
Good luck

 

The Autotune stays on the bike and comes with its own 02 sensors . Its an add on to the Power Commander .

 

Not familiar with the PC5 AT, but I do have the TMax AT and for the money and quality of ride, the AT is the way to go.
I had a PC III before the TMax and there is just no comparison in the performance. Not having to spend money on a tune for each change is a huge advantage.

 

im new to the site, but have a lot of experience with power commander products in my past years racing....

PCV was a good choice but the auto tune is not worth the extra money. After your motor work is done get it tuned at a certified tuning center and as long as your PCV doesnt drop the map (like some of the old PC III's used to), and it gets tuned right in the first place you should be A-OK

 

Do you want bar stool competitive power, or are you looking for a satisfying street ride?

You won't get as good a tune with any of the the auto tune modules as you will with the dyno tune done by a competent tuner. You may or may not notice the difference.

The problem with the open loop systems, like the PCV, is that the wide variety of crap gas around can play havoc as you blinded the ECU by eliminating the O2 sensors. They are great for making power cheap, but are at a disadvantage for all around street drivability. The tuner pro needs to add in margin (richer, lower mpg, drivability issues) to make sure the bike is not going to be pinging under any condition. Perhaps you just got a bad tank of gas?

So adding the auto tune module will provide some visibility to the EFI system at quite a price and PITA install, but what if you issue is more of a timing thing than AFR. You can easily lose 4-5 mpg trying to correct that with AFR alone.... and never be real happy with the ride (although just about anything is better than the stock calibrations)

Now that you invested in a PCV, however, it probably doesn't make sense to go back and do it right, and you do have a buddy to help out tuning it. But perhaps think about selling that PCV and getting a better tool. This is a good example where something like the TTS tuning kit and sweat equity would provide a more satisfying ride for less money... or just hire a competent tuner to sort it out.

I'm just thinking, why spend all that money on heads and cams and then throw 10-15% of the potential performance away with substandard tuning?... although many here have made that same decision and most were not burned by it.

 

Personally I think the auto-tune systems get over-sold by the makers. They give the impression that you can put their system on and it tunes itself. That's not really the case.

The downside to the PC system is that it eliminates the O2 sensors, otherwise the ECU and sensors would be fighting the PCV and they would try to bring the PC's richness back to stock. This means that tuning with the PC is a one-shot exercise; you get it tuned and that tune stays like that regardless of changes such as fuel.

To overcome that they provide an expensive bolt-on that provides O2 sensors again, but directly connected to the PC rather than the ECU. To me this is adding a fudge to a fudge, but whatever. But this 'auto-tune' doesn't tune the bike, it just keeps whatever tune you set the same if other things change. So, if you have a canned tune and an auto-tune setup, then you just maintain that canned setup.

Bottom line is that you still need to dyno tune an auto-tune system. It will do a better job then of maintaining that state of tune.

 

I was for sure doing a dyno tune . Always been a firm believer in dynos . Just wanted input on using the auto tune . I think I found my performance problem yesterday . I ran a compression test and found the back hole was down 20lbs from the front . I will have to do a leak test on it when we tear it down . I hope its leaking valves .....