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Exhaust issue!

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Old Jun 21, 2009 | 02:20 PM
  #1  
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Default Exhaust issue!

I bought Vance & Hines Big Radius (black) for my 2008 Fat Bob. I also have the new air intake for it. Will it harm the bike to install the pipes, or the pipes and the intake without doing a down load (PCIII, Fuel Pack, ect..)? I just don't have the extra money and want to put my pipes on BAD!!!

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Old Jun 21, 2009 | 02:56 PM
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Not sure about exhaust system, if you install slip on mufflers alone no fuel management is required. Less restrictive air in take fuel management required. Try a search for exhaust and or fuel management.
 

Last edited by les63; Jun 21, 2009 at 03:00 PM.
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Old Jun 21, 2009 | 03:22 PM
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I have looked for a while now and cannot find a answer if putting on my exhaust system will cause issues for my bike without doing the fuel management system. All I want to do is slap the pipes on and go for now. (till i get more dough, lol)
 
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Old Jun 21, 2009 | 03:55 PM
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Putting only the pipes on right now, is not going to hurt the bike. You might get some decel popping, but shouldn't be too bad. When you put the higher flowing air intake on, you'll need to install some sort of "enrichening" system, be it XIEDs, PCIII/V, SERT/TTS.

Even though you may have a more free flowing exhaust, you still are only pumping as much air through the engine as whatever the most restrictive component in the airflow chain will allow. Be it intake, filter, head, valves or cam.
 

Last edited by archergodwin; Jun 21, 2009 at 03:59 PM.
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Old Jun 21, 2009 | 04:09 PM
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You didnt cheep out buying the bike, the exhaust, or the intake, don't cheep out on the tune!! Lean = bad for the engine
 
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Old Jun 21, 2009 | 04:18 PM
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Pipes and Hi Flow Air Filter with no fuel management means ur running lean. This however has no to very little harm on your engine on the long run.
 
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Old Jun 21, 2009 | 05:17 PM
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Originally Posted by FatBob52
I bought Vance & Hines Big Radius (black) for my 2008 Fat Bob. I also have the new air intake for it. Will it harm the bike to install the pipes, or the pipes and the intake without doing a down load (PCIII, Fuel Pack, ect..)? I just don't have the extra money and want to put my pipes on BAD!!!

Thanks

I've had the same question as you for weeks. I bought and installed a set of Vance and Hines short shots yesterday and drove my bike around all day today with no problems whatsoever. Checked my DTC's when I got home and there were none. You're going to get all kinds of different answers to this question. I stopped at several dealerships this weekend as it's the Wisconsin HOG rallye and many of the dealerships are having parties. I asked the service reps at (4) different dealerships the same question as you and they all told me horror stories of how I'm going to burn my valves.. I need to have my bike re-mapped.. I need to have it Dyno'ed.. yadda yadda. I have to pay big bucks for the special Harley Davidson Screamin Eagle kit and to have the special Harley Davidson Fuel management system installed (SERT ?)

I thought the same thing until one of the other members quoted the pages from a place called nightrider.com. These guys have done extensive research of the ECM and how it functions when you change the exhaust and/or air cleaner. Quite simply the ECM runs in a loop pattern and will adjust whatever you do to have the throttle body maintain a constant air to fuel ratio as long as your not going over 4000 rpms or opening the throttle more than 40%. Which they say is only done 5% of the time you drive your bike.

I'm getting a set of the XiED's and going with the fuel moto stage 1 intake kit. I'll see how that goes and make up my mind whether or not to get the PC-V (5) fuel management module. From what I've read there are plenty of riders that installed these XiED's and have had great results without having to spend the $300 or so to get a fuel management module. Here's the cut and paste from the nightrider website..

Enjoy,

Christian


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.
Th 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.
 
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Old Jun 21, 2009 | 05:17 PM
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Originally Posted by Fatbob Pharaoh
Pipes and Hi Flow Air Filter with no fuel management means ur running lean. This however has no to very little harm on your engine on the long run.
too lean and you burn the pistons that equals harm in my opinion
 
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Old Jun 21, 2009 | 05:24 PM
  #9  
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Originally Posted by Harley_RN
I've had the same question as you for weeks. I bought and installed a set of Vance and Hines short shots yesterday and drove my bike around all day today with no problems whatsoever. Checked my DTC's when I got home and there were none. You're going to get all kinds of different answers to this question. I stopped at several dealerships this weekend as it's the Wisconsin HOG rallye and many of the dealerships are having parties. I asked the service reps at (4) different dealerships the same question as you and they all told me horror stories of how I'm going to burn my valves.. I need to have my bike re-mapped.. I need to have it Dyno'ed.. yadda yadda. I have to pay big bucks for the special Harley Davidson Screamin Eagle kit and to have the special Harley Davidson Fuel management system installed (SERT ?)

I thought the same thing until one of the other members quoted the pages from a place called nightrider.com. These guys have done extensive research of the ECM and how it functions when you change the exhaust and/or air cleaner. Quite simply the ECM runs in a loop pattern and will adjust whatever you do to have the throttle body maintain a constant air to fuel ratio as long as your not going over 4000 rpms or opening the throttle more than 40%. Which they say is only done 5% of the time you drive your bike.

I'm getting a set of the XiED's and going with the fuel moto stage 1 intake kit. I'll see how that goes and make up my mind whether or not to get the PC-V (5) fuel management module. From what I've read there are plenty of riders that installed these XiED's and have had great results without having to spend the $300 or so to get a fuel management module. Here's the cut and paste from the nightrider website..

Enjoy,

Christian


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.
Th 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.
thats all fine and dandy, but the factory settings are way to lean already, i wouldnt chance the longevity of my engine on the ECM being able to "compensate" for more air in and more air out... the twin cams all run "dangerously" hot without changing anything , making it worse...
ill sleep better knowing my PC111 is adding the fuel my engine needs to run cooler and last longer...
 
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Old Jun 21, 2009 | 09:53 PM
  #10  
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Thanks for the input! What I think im going to do is put on the pipes alone and run it that way. I will add the intake when I get the Dyno time and Direct link system put on.

Thanks again!
 
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