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STAND AND FIGHT!
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Discussion Starter · #1 ·
I asked this on the Dyna thread, but I'll broaden the distribution here.
Is a closed loop real-time O2 sensor controlled fuel management system
available?
 

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I asked some questions yesterday at my dealership and they seem very cagey about this whole issue,I wonder if they've been told by the factory to play any mods down.V&A pipes have the O2 sensor flanges and if your other info is correct then nothing needs to be done.I am thinking of disconnecting the diverting valve cable and see how it runs and if any codes pop up.Then if OK place an order for sideshots.
 

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Check out the Terminal Velocity closed loop system. A friend of mine had one installed on an 06 Street Bob and it rocks. I don't think he's ever put it on a dyno, but I've ridden before and after and could definately tell the difference.
 

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Datona/TwinTec is an awesome system, I can attest to That!
Have not yet used Terminal Velocity, so cannot comment - but check it out, let us know what you think and decide!
 

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STAND AND FIGHT!
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Discussion Starter · #6 · (Edited)
I think I might have a false impression of the closed loop systems accuracy, bandwidth of response, and speed of reaction. What I want to be able to depend on, and what I think really does happen in some late model cars, is the ability of the O2 sensor to cause such fast fuel enrichment, that NOS can be used dry, and the EFI will just correct for the added oxygen, and do it so quickly that you don't have to worry about lean burn damage.

In my way of thinking, this would allow turbo, and/or nitrous to be used without having to worry about either lean burn, or a mixture so rich as to cause power loss.

I want to use NOS with propane, I expect the fuel/air mixture to be more than 50 below 0, I'm pretty sure there will not be enough heat available to make the NOS and propane become a gas, I'm pretty sure they will enter the cylinder as a wet droplet fog, along with plenty of very dense very cold air. It would be beyond sweet if a dual channel closed loop system could be relied upon to almost instantly correct for some irregular distribution of fuel or NOS between the two cylinders. I envision this very high mixture density to be extra important on large displacement, low RPM, high torque long stroke engines like ours.

For bikes with kick ass turbo-boost capability, I would think that a propane bottle alone would be worth it's weight in gold. I feel fairly certain that if a Hobbs switch were to kick in at 7 or 8 lbs of boost, and start a stream of wet propane fuel enrichment, and the EFI would back off some on the gasoline to match the propane's presence, this would allow the fuel's HUGE octane rating to dominate, and it's HUGE capacity to dramatically cool the mixture to quench any potential for detonation, and that would allow the maximum level of boost the turbo-charged engine could tolerate to nearly double. That would be a pretty good trick on turbo-charged engines with a static compression ratio as high as the V-Rod.

I'm absent minded, so I don't remember where I posted this before, V-Rod forum I think, but the caption to this pix said the NOS bottle shown should last 12 to 15 quarter mile runs, where the much smaller propane bottle would last twice as long, on a 900 hp Viper.
 

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COB
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NathanG, I may have old info here, but a few years back when a buddy of mine at work would simply not stop talking about his car I got the impression that the O2 sensor was slow to react and the EFI did not react to that information very fast anyways.

Take this for what it is, simply overheard coverstation of a guy who was pretty swift on the stuff.
 

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I asked this on the Dyna thread, but I'll broaden the distribution here.
Is a closed loop real-time O2 sensor controlled fuel management system
available?
I have the Daytona Twin-Tec TCFI Wego IID system on my bike, and I love it. o2 sensor in each head pipe, closed loop operation, completely replaces the stock ECM on the bike. Only thing you have to adjust is the timing charts, but at least you know the AFR is constantly tuning itself to the preset target.

It costs a little over $700, but you never have to waste money on a dyno tune again.

Steve
 

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Just Ride
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OK I need a class. I see some of you are talking about 02 sensors, one in each pipe. Is that because each cyl has an injector with a diff lenght pipe? Kinda just thought both cyl where fed the same fuel/o2 ratio for equal power distribution?:confused::confused:Can you get by with one o2 sensor or is that just going in circles?

Darien
 

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STAND AND FIGHT!
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Discussion Starter · #11 ·
OK I need a class. I see some of you are talking about 02 sensors, one in each pipe. Is that because each cyl has an injector with a diff lenght pipe? Kinda just thought both cyl where fed the same fuel/o2 ratio for equal power distribution?:confused::confused:Can you get by with one o2 sensor or is that just going in circles?

Darien
I'm not the expert on that system, or any system apparently, but with computerized fuel control and extreme accuracy at measurement of mixture with O2 sensors, it is fairly easy to deliver fuel accuracy on a cylinder by cylinder basis, at least when you don't need 8 different control channels and 8 different O2 sensors. There will always be differences in breathing between cylinders, averaging out to match a single O2 control might be close enough, but theoretically you could do better with separate controls, both in power generated, economy and emissions.

You guys who know the Daytona/Twin-Tec system, or the Terminal Velocity system, do you know if it stays in closed loop at WFO ? Apparently, since I'm now messing with high tech LS2 engine performance mods, they do not rely on the closed loop for wide open operation, and have to be dyno tuned for big bucks.

I was hoping the technology was sufficiently fast and smart to adjust fuel flow automatically for nearly all circumstances, including supercharging or nitrous radically changing the fuel needs.
 

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Just Ride
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Hey thanks Nathang,
I was not thinking of the diff in cyl. which could likely accur, but unless they were really diff I (just me) would think you could run off 1 sensor. Not unless you want each cyl running exactly perfect as possible. Never the less watching them tune a pcII they only used one probe. Thinking of putting a termial velocity on the King. Isn't the idea to run a spec fuel/o2 ratio through out the spectrum. Nothing in order here just thoughts as they develope.
 

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I am running the ThunderMax EFI system, which is a closed loop system and it works great. Doesn't require a lot of work at all. You can fine tune the settings if desired.

You can check out their website at http://www.thunder-max.com/Products/FuelInjection/ElectronicFuelInjectionModule.aspx it is a joint venture between Zippers and ThunderHeart.

This works on all 2007 bikes. If you are 06 and below, they have another module that works as well.

Mike
 
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