XIED Frequently Asked Questions

Do I need to remap my ECM when installing exhaust and air cleaner upgrades to my 07 and later Harley?
NO, you do not have to do anything. You can put the mufflers/air cleaner upgrades and ride the bike without having to worry about the engine

The simple truth is the 07 and later HD's will run just fine with exhaust/air cleaner upgrades and you do not have to do anything to the ECM at all. Closed loop EFI operation uses feedback from the O2 sensor to maintain a constant AFR, even if changes are made to the exhaust and air cleaner.

The amount of information about what has to be done '07 and later Harley when installing exhaust/air cleaner upgrades has been the subject of FUD (Fear, Uncertainty and Doubt). Riders, Dealerships, Parts Suppliers and Aftermarket Shops have presented old-wives tales, bad technical information, mis-information and in some cases, just plain flat lied about the capabilities of the Delphi closed loop ECMs on these bikes.

Most people hold on to their old ideas about what was required for the early EFI ECM's. Shops and Dealerships never bothered to learn new the new technology. Marketing information did nothing to dispel the differences between the old and new bikes. Sales staff did not know the difference or mis-represented what was required on the new bikes.

There is more independent proof that you do not need to remap the HD EFI when installing mufflers. The March 2009 (page 66) CycleWorld dyno tested a set of slip-on mufflers on an '09 FLH, getting 5% more HP and 9% more torque on a "bone-stock, including EFI mapping" bike. Cycle World is not known as a big Harley cheerleader, so it would be a reasonable assumption that they are not going to do any special favors for MOCO.

The CW information is right in line with what HD published in the Fall 2006 Enthusiast Magazine showing a 3% HP and 7% torque increase with slightly more restrictive mufflers and air cleaner kit. American Iron Magazine has also published similar articles about "no remap" upgrades involving exhaust/air cleaner changes.

How much information has to be presented to Harley Riders that remapping of the ECM is not required for exhaust/air cleaner upgrades for closed loop bikes? When it can be shown that much of the "gain" in power for bikes remapped with expensive tuning software and piggyback controllers would have occurred without spending $400-$1000, riders need to start thinking about what they are really trying to accomplish on their bikes rather than blindly following the "you must remap just to add exhaust/ac" advice that has been discredited.

American Iron Magazine routinely presents exhaust/air cleaner upgrades on 2007>later bikes without doing any ECM remap's. As one of the premier H-D magazines, you must assume their technical staff has some knowledge about how the Delphi closed loop ECM works. So you can be fairly sure that when AIM publishes a dyno sheet with improved power and the bike did not have an ECM remap, that the information is accurate.

The Dealer told me my engine will run too lean unless I get the Stage 1 download. Is this true?

What the Dealer told you is not quite accurate. The HD Stage 1 download will not richen closed loop ECM operation. EPA and CARB emissions regulations will not allow Harley or the Dealership to make the fuel mixture richer than it currently is right now.

The Stage 1 Download does improve the Ignition Advance tables. The improvements are noticed most by Ultra riders.