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Discussion Starter #1
Well, I installed the VH Bigshot on my 02 VTX 1800R and K&n
I am getting a little popping on decel, but now bad, my question is

Will a Powercommander stop the popping?

and will I tell alot of difference? I just hate to spend money and not really see any performance difference, since alot of memebers on hear never do the PowerCommander when they ad pipes,

Thanks for all HELP!
 

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Yes but get the cheaper Cobra Unit for 159.00 or check the classifieds on this forum for used ones, it is a very minor adjustment and not worth the PC. Also read Tappers Sticky on engines and fuel at top of the page, long but good info. :lol:


Be Safe
 

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The popping will likely disappear if you do the desmog. Disable the pair valve in other words. you can find how to do it here. http://www.bareasschoppers.com/
 

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Discussion Starter #5
Ok, But will I get any more Performance by adding a Power Commander? I am really getting alot of mixed replys, I am not sure if a Power Commander is Going to really give me and more performance ?
 

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Yes a PC3 will get you more power, but you should not use it to cure your decell popping. Remove the pair system first to solve the popping. Then if you want more performance then get the PC3 and download a map from the many resources. If you want still more power then get your bike tuned on a dyno by a good tuner. 8)
 

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Discussion Starter #8
Right now I got VH Bigshots and drop in K&N airfilter, can you really feel the power difference?
 

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badwished said:
Right now I got VH Bigshots and drop in K&N airfilter, can you really feel the power difference?
Well, three of us said "Yes", but remove the pair first. Do not throw fuel at the noise to make it go away, leads to fouled plugs, bad mileage and bad smell. 8)
 

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Power commander will squeeze the extra ponies outa her!! Your bike will still run without it though. And probably very well too!
 

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Take a few minutes to read the sticky thread at the top of the page called "Air,Fuel,Motor,Missives..." and the first post by Tapper. It will explain a lot about the X engine and it's likes and dislikes. This is just a small part of it. 8)
Tapper said:
After Market Fuel Computers

This is a good time to talk about aftermarket fuel controllers, so lets hit on what they do real quick. The 1300 guys can manipulate their A/F ratios by changing jets, but it’s a bit more complex (and expensive) for the 1800 riders. For the VTX, there are basically three types of controller available. All three do exactly the same thing – they manipulate the amount of time the injectors are turned on during the intake stroke, by intercepting the voltage the ECU sends to the injectors. How the decide how much longer or shorter to turn the injector on, varies a bit though, and that variety is important thing to know when selecting which controller to use on your bike (if in fact you choose to use on at all – none of them are ever really necessary, regardless of what pipes or airboxes you add on to the bike.)

It’s also important to understand this: None of these controllers is ever a necessity, regardless of whether you change pipes or airboxes on your bike. The stock ECU will, in almost every case, adjust to the changes in airflow you’ve caused, and give you a reasonably good A/F ratio. But you should understand, that the ECU is not programmed to give you an A/F ratio that is optimized for horsepower from the factory – instead, Honda worries about things like pollution, engine temperature, and rider perception, and so the ECU can be said to be “de-tuned” in order to address these other concerns. So the real function of these add-on controllers is to correct the error (or eliminate the de-tuning) that Honda induced in your fuel curve on purpose, in order to reclaim the lost horsepower and improve engine efficiency (possibly at the cost of making more pollution, hearing more deceleration backfiring, etc). Adding on aftermarket pipes or airboxes can sometimes exaggerate this de-tuning as well, so we need to be able to modify our fuel curves to match the configuration of our bikes. Got that? These boxes aren’t necessary, but if you’re hunting more horses, they can sure find them.

So lets talk about the specific boxes:

TFI – This unit is marketed under several brand names by Techlusion, Cobra, and others. It does one thing, and one thing only – it extends the fuel pulses produced by the ECU, and therefore, it can only richen the fuel mix – and never ever lean it. Typically, these units are designed to act like variable fuel jets – by adjusting two or three settings, you can add more or less fuel to the mix for a certain RPM range – usually low, middle, and high. It determines RPM by looking at the signal frequency produced by the ECU. Because these units are extremely simplistic, they won’t really optimize your fuel curve, although that can reduce or eliminate decel popping, or sometimes correct a really lean condition, But in all cases, your fuel curve will vary from lean to rich along it’s total fuel curve, so you’re only going to help the lean spots, and hurt the rich spots. These units get sold with a lot of pooey about bikes always being lean, or “knowing load”. It’s cap, since we’ve seen hundreds of fuel curves off the dyno now that amply demonstrate that most VTXs run a little lean at low rpms, and rich in higher rpms (as a rule, but not always). This load nonsense is just that, since all of the available fuel controllers modify the signal produced by the stock ECU. Therefore all of them “know load”. Don’t get suckered by marketing malarkey. Frankly, while these units can reduce decel pop, I can’t see that as a goal worth achieving, and so I never recommend these units. I think you can do better, for slightly more money.

Power Commander III – This device also modifies the fuel output from the ECU, but does so based on a table of values referencing the throttle position sensor (TPS), and rpms. Since the position of the throttle plates directly affects the amount of air being allowed into the engine, the value of the TPS is a pretty good substitute for the “Load” value derived from the map sensor by the ECU. In effect, the PC3 produces an overlay curve of its own, and this can be manipulated to correct the de-tuning in the stock ECU. PC3’s can either lean or richen the mix, and so are capable of completely correcting the fuel curve produced by the stock ECU. Because the new curve is applied proportional to load, its effective regardless of the ambient air pressure – since the curves are proportional. Tuning the PC3 correctly requires a session on a dynometer, so these units are somewhat expensive – but set up correctly, they will produce optimum fuel curves under nearly all conditions. Of course, changing equipment on your bike will mean the curve is no longer a perfect match, and another adjustment session will be required in order to get a perfect fuel curve, so the PC3 is not without its gotchas. But for best performance, the PC3 comes out on top. It’s a very flexible and effective unit. Newer PC3’s also have functions that can emulate a tunable accelerator pump, or allow you to map each cylinder independently. Good stuff.

HPP – This unit adjusts the output fuel pulse by manipulating the value of the MAP sensor, based on calculations derived from reading the oxygen content of your exhaust with an O2 sensor. In theory, this results in a “closed loop” system, one that adjusts itself looking for optimal F/A ratio by reading the exhaust in real time. In practice, the O2 sensors are pretty inaccurate at higher RPMs, and so the device does some educated guessing, and therefore the fuel curve isn’t always perfectly optimized. However, experience has shown that properly set up, these units perform very well, and are an excellent alternative for someone who doesn’t want the hassle of fiddling with their fuel tables, or going to dyne sessions. They can also adapt immediately when new equipment is installed on the bike. So this is the unit to use when performance with convenience is your goal, and you are willing to give up a few percent of horsepower to gain that ease of use. Good stuff here too.

Alas, there is currently no unit on the market which can manipulate the timing tables, and that sucks. These big motors cry out for the ability to optimize timing tables to match configuration or changes to the fuel tables, and there’s no doubt that 4 or 5 horsepower lurk in the inability to manipulate the spark. Perhaps someday Dynojet will follow through on their promises to provide a timing module, but until then, the ability to manipulate spark effectively simply doesn’t exist. I yearn for a fully programmable ECU. I also yearn for a 20 year old hottie with great legs and big boobs. I’ll probably get my timing before I get the boobies though – more’s the pity.
 

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Discussion Starter #13
ok, thanks again, also I bet the the ignition modules is released and we can adjust the timing, the PC3 is really going to make the 1800 scream
 
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