Hi Folks,

Somewhat new to the forum so nice to meet you all. Got my first Harley back in October. 08 FLHRC. 2-tone red. Been spending all winter customizing it for a retro lookand am beginning to realize what people mean when they get bit by the chrome bug!

Anyhow, I called my dealer today and asked about the Harley stage I download (the one that doesnt require a SERT). I am putting a K&N a/c on the bike as well as Rush 2.5's. Thats all. Dont want a PCIII as my powertrain enginering background maskes me believe the SERT is a better designedpiece of software and ECM interface overall. Plus, I plan to take advantage of the 02 sensors to aid in fuel economy improvements, not bypass them.

My dealer told me the Stage I download isn't good. Something about a "baseline map" but I dont know if the tech even knew what he was telling me. I assume the stage I increaes the max RPM to 6200 and adjusts for the reduced pressure drop through the air filter. Does it adjust at all throttle and RPM levels as well?

If it can get me 90% there, then do I really need a $400 SERT or can I wait until I do a true dual or 2-1 setup?

Thanks and look forward to future discussions. LOVE my King (well, except for 5th gear whine and wimpy stock exhaust note)

 

I dont think u would need one i went through this on my 06 i did a download then when i put my true duels on i sent the money and got a sert works great..good luck..

 

Any downloads that you would get from the dealer still are restrictive in tha they are designed to still be EPA compliant and wont change the tune much, but if just going with a freer flowing air cleaner for now, it cant hurt.

The SERT is by far the better way to go, especially if you are computer savvy enough to learn the system and do a little tuning yourself. Dealers will usually sell you dyno time to dial in the SERT and to get the A/F right. You can do this yourself without the dyno, but it takes time, and some trial and error. An addition to the SERT is offered by Headquarters, the Pro-Tuner which will automatically adjust the A/F as conditions change - altitude, temperature, changes in exhaust, etc in conjunction with the SERT. Other options are the T-max autotune and the DTT TCFI II (I am running the DTT) which are systems that you can fine tune from your laptop and again make changes to keep A/F where you want it. Time for you to do a little reading- search each of the systems on this forum, there is a lot of info on them.

 

Yes, I have done a lot of reading on PCIII vs T-max autotune vs SERT and having the ability to calibrate like the harley engineers do without the aid of a signal conditioning box such as PCIII seems like the best solution for me.For those who are happy with their PCIII's, no disrespect. Tmax with auto tune is pretty clever too. My gut instinct just tells me that any piggyback that eliminates 02 sensors as part of its designis not engineered the way I would like. 02 sensors are GOOD things when used they way they are intended. I.E. part throttle cruise conditions. Not sure how the PCIII can adjust for ambient, barometric pressure, and humidity to get the best fuel ecomony at low throttle conditions. Thats where functional 02s should be helpful.

I understand about the EPA stuff. Thanks. Doesn't sound like it willhelp the heat problem on the right leg when in traffic.

Does the SERT come with some stage suggested maps that I can download like the PCIII does?

 

First, you are correct that "02 sensors are good things when used they way they are intended," but the HD system uses narrow-band O2 sensors which are very limited in scope. These work in a very narrow range, at idle and in portions of the cruise range at <50% throttle, doing little except regulate A/F to stoich (14.7:1) to meet EPA regs. Stoich in a water-cooled engine are quite different than stoich with an air-cooled HD engine. Second, the PCIII doesn't adjust for any conditions (humidity, air temp, etc.) in itself, but the ECM in open-loop mode will using the sensors already on the bike. Third, the PCIII can be adjusted in 1% increments from -100 to +100%, as well as ignition advance, overriding the signal provided by the ECM--and each cylinder can be tuned individually, so if you want to tweak the cruise range to a leaner burn you can do it. I've done that on my map and it has resulted in better gas mileage without any performance loss. I also run a map switch for the PCIII which allows you to switch on the fly. This is useful by loading one map for mileage and another for cooling in times of heavy traffic in hot weather. I know of no other EFI controller that will do this.

It is a misconception that the PCIII will not work in closed-loop mode. It can work with O2 sensors connected, but when in closed-loop the ECM will override any input to maintain stoich in the affected TP and RPM range, including any PCIII changes. IOW, if you have a +5% in one block (e.g. 2k RPM @ 20% TP) the closed-loop function will regulate it to stoich the same as if it was set to "0", "-5", or whatever. So the PCIII setting won't work if in closed-loop mode and if in the range affected. However, outside this range (e.g. WOT) it will work as designed.

Any time you have the stock O2 sensors connected you have lost control of the range controlled by closed-loop mode, unless you run SERT, which allows you to set closed-loop mode from 14.7 to 14.2, which is a useful function and gets A/F down to a workable level that won't overheat the engine as much. But since closed-loop works in such a narrow range it isn't doing much other than make the bike EPA certified. If you install the Stage 1 download after adding pipes and AC, you still are within EPA guidelines and aren't helping any or much with the heat problem these newer bikes suffer with. So Stage 1 only sets the ECM to run similar to stock in terms of A/F and emissions, tailored to the new hardware.

Wide-band, closed-loop systems like T'Max autotune exist, but they are pricey. These operate in a much wider range than the narrow-band HD system, and with the configurability they have are useful for minor hardware changes without a dyno tune. However, it is a misconception that these wide-band systems will auto-tune for any change. To work properly the starting point must be very close to correct or auto-tune won't do its job. For this reason I think they are limited, and I still think the PCIII with a properly created canned map is the best bang-for-the-buck available.

I understand that downloadable maps for SERT are limited mostly (entirely?) to HD combos (SE pipes, Stage 1 AC, etc.), so if you install SERT with third-party equipment you likely

 

A DOWNLOAD on a '07 - '08 is just throwing your money away.... Get a SERT or any FuelManagement System