Yes, when it is open loop it runs rich for the stock air filter, but when you change the air flow you change the amount of air mixing with that rich setting, thereby changing it to lean mix with a hi-flow filter. In order to compensate it needs to be remapped or a fuel management system needs to be installed, regardless of internal mods or exhaust. The IED/XIED only works when the system is polling the O2 sensors, which is at idle up to 1/4 to 1/3 throttle.

 

gaffney - You may be right, but I didn't think a bike with only slip-ons and AC could take it from overly rich in open loop to overly lean. If that were so, then it seems like H-D would be opening up a big warrantee can of worms with their stage-1 download.

 

They say that installing the Screamin Eagle Stage 1 AC by itself requires reprogramming the ECM (or ECU as I sometimes call it ). You can check that out if you have their catalog, at least it says it on page 505 in my 2009 parts catalog. It says "All EFI equipped models require ECM recalibration" and "Recalibration is required for proper installation and will allow engine to rev to 6200 RPM." I think that covers staying within their warranty guidelines.

 

You just proved my point (it says the same thing on page 520 of my 2008 catalog BTW). The "ECM recalibration" they are referring to is the stage-1 download. The download does not change the fuel mixture in any way. It would be in violation of EPA if it did. All it does is alter the timing curve and raise the rev-limiter. Since Harley themselves do not change the AFR when adding the SE AC, how could it (the AC) be leaning out the mixture dangerously in open loop?

 

I am running the Fuel Pac and xied's, I have no flat spots or hesitation anywhere. A fuel management system is what you are lacking.

 

Thankx guys, I understand what everyone is saying...this is always an interesting topic for discussion. I read this months ago posted at nightrider.com:

"Harley-Davidson did publish some interesting power improvement percentages in the Fall 2006 issue of its Enthusiast newsletter. From the information listed below it must be assumed that you can upgrade the exhaust system and intake system on your 96CID engine without any changes to the ECU. Nightrider has historically been a proponent of exhaust system only upgrades with no EFI remap, but now HD has published that HD/SE exhaust upgrades and no EFI upgrades can be added to your bike without warranty implications."

I guess that's why I'm a little confused on remapping for just A/C change..

 

I hate to carry this on further, but I fail to believe that changing the fuel to match the increased air flow would violate any EPA mandate. As a matter of fact, running too rich would be a worse situation for the environment since you would be pumping more unburnt fuel into the air and onto the ground. Also, if increasing the fuel would violate EPA standards, wouldn't using an after market fuel management system or having the system reprogrammed at a dyno shop be in violation? I don't buy that argument.

But you may be right regarding their stage-1 recal (as I have no way to verify what it does).

Ronyd, I think Harley changed their EFI setup since that article was written. If I recall correctly, their initial systems were always running in open loop because there were no O2 sensors. They had to program the ECM to run extra rich all of the time to cover just about all envorinments the machine could be ridden in. That might be why no remapping was needed back then. But don't hold me to that, it is coming from my memory of reading some article a long time ago.

In any event, you can always take your bike to a dyno shop and have them check your air/fuel ratio to see if you are running too lean. Then they can remap if necessary.

EFI is a complicated system and is just outside of my comfort zone. All I know for certain is that according to most of what I've read online, which contradicts what Mr. Lucky is saying, is that Harley's are programmed to run lean from the factory. Applying my experience with carbureted engines, when changing the intake up to the carb, you need to rejet the carb to supply more fuel. So, applying this logic, you can deduce that when doing the same to an EFI setup you will need to supply more fuel to the mix to compensate for the added air.

I would suggest that you do some more research to verify for yourself just to be sure. I am far from an expert on EFI systems. Just sharing my memory of the info I've come across in my research.