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Discussion Starter · #1 ·
I have a fuel injected fatboy. Stage 1 kit, exhaust, etc... Is there anything else i can do to get more power and not too expensive?? My shop is trying to talk me into some fuel processor called Cobra.
What about a SE coil, etc???
 

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utoypia said:
I have a fuel injected fatboy. Stage 1 kit, exhaust, etc... Is there anything else i can do to get more power and not too expensive?? My shop is trying to talk me into some fuel processor called Cobra.
What about a SE coil, etc???
Do not buy a Cobra,or ANY pot type unit ...they are all N F G ...I am sure you nead some help with your air/fuel ratio..there are only two systems that work with your stock ECM , Harleys SERT or powercomander ...I find the power comander much easier to custom map on the dyno .:boobies:
I dont think a SE coil will help at this time :whisper:

Good Luck

Steve The Dyno Guy :cheers:
 

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I think what you are looking for is Horse Power you can feel.

Meaning a modification that will open your eyes and wake you up when you get on the throttle. None of those mods will do it in my opinion. They may show a few ponies on a dyno, but nothing you can really feel. No knock you back in the seat change.

Save your money and do it right. When the time comes, find a good builders package and get some cams, headwork, and 95" kit. If you want bigger and more expensive, then get a 103 and change the crank.

That is when you will see a Big Difference.
 

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Discussion Starter · #4 ·
Steve Handy said:
Do not buy a Cobra,or ANY pot type unit ...they are all N F G ...I am sure you nead some help with your air/fuel ratio..there are only two systems that work with your stock ECM , Harleys SERT or powercomander ...I find the power comander much easier to custom map on the dyno .:boobies:
I dont think a SE coil will help at this time :whisper:

Good Luck

Steve The Dyno Guy :cheers:
What is a pot type unit?? When I mentioned Power Commander, the guy didnt talk highly of it. He recommended the Cobra as I said. Why do you call it a pot unit?
 

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Steve Handy said:
Do not buy a Cobra,or ANY pot type unit ...they are all N F G ...I am sure you nead some help with your air/fuel ratio..there are only two systems that work with your stock ECM , Harleys SERT or powercomander ...I find the power comander much easier to custom map on the dyno .:boobies:
I dont think a SE coil will help at this time :whisper:

Good Luck

Steve The Dyno Guy :cheers:
take this advice. pot devices are band aids at best. if your shop thinks more of the cobra than the PC, you may wanna rethink who you allow to work on your bike.
FWIW, there is another option, the Thundermax at ZZippers.
 

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utoypia said:
Why do they call it a pot unit??
a series of potentiometers. basically these units alter the voltage going to the injectors.
example. tps says .9 volts and ecm sends 300 milivolts to the injector for .05 seconds. the pot can alter this signal to 400 milivolts for .08 seconds, meaning more fuel goes through the injector with each pulse.
others may alter voltage from tps to read something like .94 volts, again tricking the injectors to have a longer pulse.


note: figures are not accurate, for example purposes only.
 

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Maybe I'm assuming too much, but with a stage 1 kit you do have exhaust and breather right? Even if you went with a cam and power commander then, you should feel the power. On my 01 Road King I went with the Andrews 37 cam and went from 62HP, 72 ft/lbs TQ stock to 79 HP and 85 ft/lbs. This was noticeable and with a power commander, under $800 if you do it yourself.
 

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utoypia said:
I have a fuel injected fatboy. Stage 1 kit, exhaust, etc... Is there anything else i can do to get more power and not too expensive?? My shop is trying to talk me into some fuel processor called Cobra.
What about a SE coil, etc???
OK, there's one thing that new Harley riders need to know when rebuilding an engine. If you want a good performing bike, forget about horsepower and start concentrating on TORQUE. HP is worthless without the torque to get it to the ground. What cams do you have now? You want to go with the shortest duration and highest lift that your bike can handle without major, expensive headwork. Don't worry about getting the highest numbers on the dyno. If you are getting very high HP numbers, you are most likely hitting them at rpm's that are much higher than the range you usually ride in and are therefore wasted.

The Twincam's heads (it is a Twinkie, isn't it??) basically suck, so it wouldn't be a bad idea to get them done as soon as you can afford it. Exhaust choice is also a major factor. You can usually tell if someone is more concerned about performance or appearance. Those who have a 2-2 system usually are more concerned with looks and/or sound. Those who want the best performance almost always run a 2-1 system.

Stick with the basics if you are on a budget. Intake, exhaust, cams, ignition (tunable), and most important thing.... dyno tuning by an EXPERIENCED tuner (usually NOT at the dealership). As for SE parts..... personally, I do not like them. I always buy aftermarket items, but that's just me. Have fun! :)
 

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The Pottensiometer units basically take a nice, specific, 108 or 128 cell mapping procedure and basically gives it the same adjustment range as a 3 circuit carb. Good for doing very basic tuning on the EFI. No timing adjustments either. To take a very accurate system and reduce it to low, medium, and high, is the reason a good tuner doesn't like (or use) them, including myself except for a guy who has done basic pipes and AC and is not going to be doing anything else. Then it can be used to remove decel pop and take out a general lean condition. If the shop doesn't have a dyno, he'll just be guessing as to the adjustments anyway, whether it be a Powercommander, SERT, or whatever, and my guess is that he doesn't. SE coil on an EFI?? Forget it! Steve H and claydbal already gave some advice as to what they thought of the Cobra, etc, devices. I third the motion. Figures the dealer would recommend the simplest device. BTW you can order the thing yourself and it gives you the settings for the POTS for many combos that you do yourself with a small screwdriver.
As ToddM says, power you can feel is attained with more serious mods than an EFI module in your case. And the thing that will kick you in the ass on a twin cam engine is Torque, torque, and more torque.
 

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A few days on this board will give you access to dynos, experienced wrences, hot setups and people that actually have and use these setups. Now if you want to put faith in your local wrench then it's your money. But not once here have I even seen anyone even bring up the Cobra product. Not because no one knows of it, simply because it's crap. Your only path from the point you are at now is going to be internal. Heads, Cams, etc.... I'm surprised that you don't have a Power Commander or a SERT right now seeing as you have the Stage 1 upgrade. Your bike has to be running pretty lean.:whistle:

I would be worried about the lean condition first off before I went any further. Even with the dealer download to the ECM, you still need more air/fuel adjustment. You won't find more experienced people in one group as you will here. You most likely need to look into a Power Commander or a SERT first. Then decide how much power you want to make. The guys here can help you get there the right way without being "F" over by your shop.
 

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Discussion Starter · #13 ·
Powver commander

OK, you all talked me out of the cobra... So, What is a SERT? WHy would one choose Power Commaner over a SERT or vice versa? My bike has the stage 1 kit. SE breather, V&H exhaust, HD dealer remap. What would adding a PC do for my bike?? It it plug in play? Can I just plug it in and go? DO I adjust it myself?

I wouldnt mind a little extra horse power but ultimately, I'd rather have my bike running like a champ (air/fuel ratio, etc...) no matter how much hp it puts out...
 

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The first thing is to ask around for a competent dyno tuner in your area, and ask what he prefers. You'll spend a couple of hours on his dyno getting it tuned right. He's going to run the piss out of the bike, but if he knows what he is doing with either the SERT, or the PCIII, he'll get the most power out of your build. The cost at my local dyno shop is 300.00 for a custom map.
 

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b-footn said:
The first thing is to ask around for a competent dyno tuner in your area, and ask what he prefers. You'll spend a couple of hours on his dyno getting it tuned right. He's going to run the piss out of the bike, but if he knows what he is doing with either the SERT, or the PCIII, he'll get the most power out of your build. The cost at my local dyno shop is 300.00 for a custom map.
Speaking of dynos..... do not do a complete (max rpm) dyno run until you have at least 1500 miles on your engine. It won't be fully broken in until then, and will not be capable of making the most power. Most shops will do a partial power run to get it tuned well enough to get you to that point.

A good ignition system would be something like the Daytona Twin Tec, Dyna 2000i, or Crane Hi4. (I prefer the Dyna 2000i)

Basically, ANY changes to your engine (carb or EFI/timing/exhaust/etc.) are NOT "plug and play". You should always tune it on a dyno after making any changes. Failure to do so may result in decreased performance at the least, or (in the worst case) decreased engine life (or even major damage). You can get the tuning close "by ear", but it won't be right until you can get the AFR set correctly across the entire rpm range. :coffee:
 

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Bottom line is finding a good tuner and then find what he is good at, ie SERT or PC. I know of many customers that have told me that they have tried a few tuners without luck and have to go several hundred miles to a tuner. All have said well worth it.

As well as a few that choose not to have used a DFO style device. I my self have tuned bikes that had them and have fairly good luck getting a good afr curve. Depending on items installed of course,
 

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SERT stands for Screamin' Eagle Race Tuner. If there is a shop in your area that is set up with tuning link software and a Dyno Jet dyno,then I would go with the powercommander. Check powercommander.com to find an authorized tunig center. SERT does do some things that the PC cannot,you canget into cold start tables change idle rpm's and so forth. Have the bike dyno tuned with either set up.
 

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air/fuel alterations on EFI

In this month's American Iron, there's an article which discusses the new type which adds an O2 sensor to each exhaust manifold (like cars and trucks have had for many years now) which continuously reads the A/F ratio by reading % of oxygen in the exhaust and adjusts the A/F ratio accordingly. Just like a car or truck. HD uses a similar system on '06 Dynas--precursor of the future probably.

This is called a closed loop system instead of an open loop system like all other HD EFI systems. Open loop doesn't monitor exhaust in any fashion.

The author (Heavy Duty Cycles) likes the new system. Of course, to install on anything other than 06 Dyna you have to drill a hole and weld in the fitting for the sensor. Probably not a job for those who don't weld.

I'm not sure I'd like to be a first year guinea pig test pilot either. But pretty soon these will be on all bikes, probably followed by catalytic convertors. Can you spell BMW anybody?
 
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