Exhuast mods w/o tuning
Extreme HDF Member
Joined: Apr 2006
Posts: 10,449
Likes: 46
From: Roswell, GA
Masterblaster, I don't think you're needling me. But a lot of people call a vendor and talk to a guy whose credentials are undisclosed and rely on that person's advice/opinion as the holy grail.
As glens men tioned earlier, even assuming the ECM can adapt to provide more fuel at cruise, the ECM is "dumb" and won't add fuel in the other rpm/load conditons in which I do most of my suburban riding, and that will inevitably be an excessively lean condition given that HD has the ECM programmed in those areas at 14.6 or so.
Honesty compels me to say that I'm not an expert; far from it. More complete knowledge can be found with PhilM, Dalton, Doc1, and others on this forum who have far more experience tuning engines than I have and are more familiar with the '08 and newer ECM's to add fuel when in closed loop operation.
Hope you are pleased with your mods--ride safe.
As glens men tioned earlier, even assuming the ECM can adapt to provide more fuel at cruise, the ECM is "dumb" and won't add fuel in the other rpm/load conditons in which I do most of my suburban riding, and that will inevitably be an excessively lean condition given that HD has the ECM programmed in those areas at 14.6 or so.
Honesty compels me to say that I'm not an expert; far from it. More complete knowledge can be found with PhilM, Dalton, Doc1, and others on this forum who have far more experience tuning engines than I have and are more familiar with the '08 and newer ECM's to add fuel when in closed loop operation.
Hope you are pleased with your mods--ride safe.
Ultimate HDF Member
Joined: Dec 2006
Posts: 8,961
Likes: 263
From: Conroe Texas
Thanks guys, I will stick with just pipes for now, will add the a/c when the Super Tuner arrives and I can do a stage 1 download myself. I just pickewd up my 09 yesterday and the bike is running pretty lean, can tell by the heat even at speed. Again, Thanks.
Last edited by masterblaster; Sep 20, 2008 at 04:47 AM.
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Joined: Jan 2006
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Just an observation on my 2009 FLHRC. I put a set of 1.75 Wild Pig slipons on last week. When I took off the stock exhaust the inside of the pipes was dark tan to almost black. This was with 3000+ miles on it most of which was highway riding going out to Milwaukee for the 105th.
Now I'm no expert but if these bike are running as lean as everyone says wouldn't the inside of the pipes have been a light tan to almost white ? Just wondering if there might be a little urban legend stuff going on here.
Now I'm no expert but if these bike are running as lean as everyone says wouldn't the inside of the pipes have been a light tan to almost white ? Just wondering if there might be a little urban legend stuff going on here.
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Road Captain
Joined: Jun 2008
Posts: 561
Likes: 0
From: Amelia, Virginia
Just an observation on my 2009 FLHRC. I put a set of 1.75 Wild Pig slipons on last week. When I took off the stock exhaust the inside of the pipes was dark tan to almost black. This was with 3000+ miles on it most of which was highway riding going out to Milwaukee for the 105th.
Now I'm no expert but if these bike are running as lean as everyone says wouldn't the inside of the pipes have been a light tan to almost white ? Just wondering if there might be a little urban legend stuff going on here.
Now I'm no expert but if these bike are running as lean as everyone says wouldn't the inside of the pipes have been a light tan to almost white ? Just wondering if there might be a little urban legend stuff going on here.
Outstanding HDF Member
Joined: Jul 2007
Posts: 2,609
Likes: 1
From: Indy area
...The guy at the Indy explained to me how the ecm works concerning open loop and closed loop. I used to work at a Chevy dealer doing driveability troubleshooting. That is why I was wondering about why people where telling me that the ecm couldn't correct the lean condition. The ecm in a car goes into closed loop once the 02 sensor heats up and it stays in closed loop. The guy at the Indy explained to me that the bike goes into open loop during hard pulls and relies on the programed parameters rather than 02 readings to control AFR.
In our EFI the amount of air flowing through the engine is not measured directly in that fashion. It's instead derived based on values set in the programming. Whenever those values become incorrect because we've changed the airbox or exhaust (or cams, etc.) the open loop operation will be mostly incorrect in terms of fueling. We have a limited type of autotuning but it is not meant to correct for different parts. Rather, its function is to maintain the desired AFRs for the breathing parts its programmed for in the face of maybe low/high fuel pressure, an injector not functioning entirely properly, etc.
It senses any such changes while operating in closed loop and then uses the same corrective factors while operating open loop. If you change parts relative to the EFI programming, it will pick up those closed-loop changes and use them open-loop too, but this is rarely correct since different parts rarely change the breathing characteristics the same across the board. If the parts did merely flow the same percentage better everywhere and it was within the range of the autotuning feature, it would work correctly.
Look at the images I linked to earlier in this thread and see for yourself how the programming is different for different combinations of parts. There's no way our autotuning will work correctly everywhere in those cases and it should not be relied upon to do so.
Extreme HDF Member
Joined: Sep 2008
Posts: 15,259
Likes: 5,383
From: Delaware
This whole issue of pipes vs pipes and ac vs pipes and ac and tuner is very interesting. Someone else mentioned his dealer suggested Rush slipons with the 1.5 or 1.75 baffle. My dealer swears by, (and sells quite a few), Rush slipons with the 2 inch baffle. I just installed a set on my bike. Before doing so, I emailed V&H because I was really more interested in a set of their pipes. My question was, if changing only the stock mufflers to their X model slipons, would I need a remap? Their response was no change should be made without a remap.
I believe this is one of those issues that only a couple hundred thousand miles and a few thousands test subjects will answer.
Glens, thank you for clearing the question about why the ecm doesn't self coorect like a car. No one at my local shop knew the answer to that.
I believe this is one of those issues that only a couple hundred thousand miles and a few thousands test subjects will answer.
Glens, thank you for clearing the question about why the ecm doesn't self coorect like a car. No one at my local shop knew the answer to that.
Road Warrior
Joined: Dec 2008
Posts: 1,616
Likes: 17
From: Mid West
I have an '03 FLHRI, 100th anniversary edition and just not satisfied, it was bought used with Hooker slip-ons which for me and the little woman, too loud; any thoughts on a stock 88 that I want to cam for low end and add V&H true dual with Monster Ovals?, look great and from what I've been around talk low and a little louder than stock.
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