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Ok, I know there a lot of threads out there about this, but I am confused.
Can I do a complete exhaust change, header pipe and slip on without having to remap. I was just at the dealership and the service manager told me I need to do a stage 1. He quoted me $1300. I already have Rush Big Luey slip ons and have Corba header pipe in the garage. That price seams very high, just for labor and intake and remap.
Thanks for the help.
 

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from what i have read/heard/experienced, you can do the exhaust or you can do the intake without a ecu ( computer/cpu/whatever you call it) remap. basically it comes down to what the stock ecu can compensate for. so if you just do the exhaust, you shouldn't need a remap. now, for what it's worth, your stock bike is already running lean from the factory due to EPA regulations. so allowing more air through the system is going to make the lean condition more lean. the stock ecu should be able to compensate for the extra air, but it will still be lean. add a higher flow intake and you have surpassed what the stock computer can makeup for. lean is hot. hot is bad for an air cooled engine. if you are doing any mods you should really look at an aftermarket fuel controller (power commander or similar) or a computer flash/remap. even if you keep the intake/exhaust stock, your bike will benefit (performance wise) from the fuel controller/remap.

kgb
 

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Yes you can do just mufflers without a remap. I did a 5,000 mile ride to Sturgis last August in some of the hottest weather we've ever had. One of the bikes with us was a '07 Electra Glide with a Thunderheader exhaust and Arlen Ness big sucker air filter. He had NO download or fuel pack. I kept comparing oil temps with him, and his was almost the same as mine. He has now added a fuel pack and says it pulls better, but the mpg took a hit.
 

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I had SE slip Ons and HiFlow air in with no maping. Changed the cam up a size and put in a fuel pack. It sucked and the shop tossed it and did a Stage 1 map. Runs much better. Power up, mileage the same.
 

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the stock ecu should be able to compensate for the extra air, but it will still be lean. add a higher flow intake and you have surpassed what the stock computer can makeup for.
It's my understanding that this is incorrect.

Your electronic fuel injection system uses the O2 sensors in the exhaust to adjust the mixture. You will be running lean, this is true, but you will be running the same amount of lean as you were before at factory stock.

The point of changing the map (the 'stage 1 download') is to richen the mixture, giving you a boost of power, but you won't risk any particular damage by not doing it.
 

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Fat Guy on the Ultra
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Ok heres what my years upon yrs of research have yeilded.
Stock afr is about 14.7/1 epa ok lean

Adding slip-ons, frees up power by getting exhaust out of engine. No afr change

Adding air cleaner and slip-ons, puts afr leaner at about 15.2/1 very lean.

Slipons, ac and stage 1 download puts afr back to stock 14.7

I did slipons, stage one ac and download and xieds, and im running good, according to black plugs, not white anymore. So i think afr is about 13.9/1 now.

stock ecm and wide band o2 sensors can only compensate for so much. Now if it.had narrow band sensors then maybe...
Stock ecm map only has parameters for so much of a varience. O2 sensor send back a voltage reading to the ecm and it looks at the table and says for that input voltage then it has a desired action. If you lean the afr out beyond what the ecm is programmed for then it doesnt know what to do.
Eg. Lets say with stock setup, you are at the 14.7/1 afr. O2 is putting in a voktage of 5 volts to ecm, ecm says ok that good lets keep fuel where its at. Now lets say you add ac and slipons that bumps your afr up to 15.2/1, and sensors send in a 2 volt signal, ecm say, under 3 volts add x amount of fuel to the base amount., which only changes afr to 15.1/1, which is still lean. Remember the stock ecm is designed to accomodate for elevation changes only, not the increased amount of air putting a high flow ac on will introduce to the system.
Thats why its recommeneded by moco to get stage one download when adding the stage one parts. That gives the ecm a new chart to tell it what to do now with the new o2 vomtages, and also gives it more fuel as a base amount so now the afr is back to the stock afr of 14.7/1.


But mind you i have only read the same stuff everyone else has. I just applied this theory to my bike and she runs like a dream. My old 2010 i had ac and slipons and didnt get download or xieds and she popped and crackled like crazy and ever service i was told ahe was running to lean. Changed plugs every 5k cuz they were burning up. Plugs on new bike are noce and black like supposed to be. And no popping at all....
 
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