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How many people are really using the BAP with their KB install? I have heard from more then one source that it is not needed and most people that have them installed are actually running with them disabled. I was planning on running 50# injectors, but was going to buy the KB without the BAP if it is not needed.
 

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im running stock inj so i have mine hooked up but i dont know if its actually doing anything..fuel pressure on the dyno was 58 max with the BAP turned all the way up...diablo chip though
 

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I have heard that if the tuner can controll the fuel pressure in the tune the BAP is not needed. I am actually going to tune my car today and see what they can do. It more than likly will not be needed but I will keep it in the car just cuase its so dam purty.:cool:
 

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Snake Charmer
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I also plan on running stock injectors so if need be I can put the stock KB pulley on and run with no chip. I dont like the idea of having to have a chip to just run the vehicle. I dont have it installed yet but plan on using the BAP if needed, which it likely will be with 17psi.

As for those using the BAP and getting lower PSI, KB states that you should see 80psi, but thats also for 21(or was it 22)PSI so if your running less than that you wont require as much fuel pressure.
 

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I have a KB with a BAP and stock injuctors runing 18lbs. I run the BAP at about 25% with 60psi fuel pressure. The BAP is a voltage regulator, it keeps the voltage to the fuel pump at 12/17 voltage as required. Increasing the voltage to the fuel pump, incressures the fuel pump flow at any pressure.

AMB
 

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The Ubiquitous Jimmy V.
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AMB said:
I have a KB with a BAP and stock injuctors runing 18lbs. I run the BAP at about 25% with 60psi fuel pressure. The BAP is a voltage regulator, it keeps the voltage to the fuel pump at 12/17 voltage as required. Increasing the voltage to the fuel pump, incressures the fuel pump flow at any pressure.

AMB
Are you useing the KB chip??Other are have problems getting there BAP work that way..
 

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I have both a KB chip and a Ford Chip/JMS Chip Corp. (Diablo Revolutiom) Chip. The KB BAP does not need a chip to work. It only increases the voltage and regulates the voltage to the fuel pump.

AMB
 

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The Ubiquitous Jimmy V.
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Cool..So in your case it works well with either chip.
Not all tuners have a handle on this BAP yet..
Kenne Bell stated in there Information to use the BAP with there chip..
 

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The KB BAP and the increase in fuel pressure are different problems. The increase in fuel pressure, if required, is done in programing the chip/computer. The KB BAP only supplies the extra voltage to the fuel pump,if required, for the increase in fuel presseue.

AMB
 

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The Ubiquitous Jimmy V.
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AMB, Thank's for the Clarification..Much Appreciated.:)
 

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AMB said:
The KB BAP and the increase in fuel pressure are different problems. The increase in fuel pressure, if required, is done in programing the chip/computer. The KB BAP only supplies the extra voltage to the fuel pump,if required, for the increase in fuel presseue.

AMB
Thanks for the input, AMB but I am confused. If the BAP is properly installed, then we can safely conclude that, when it is turned on, it is supplying extra voltage to the fuel pump, effectively making it work harder and supplying extra GPH of fuel.

But if the chip is not programed to ALLOW that extra fuel pump work to affect the engine performance, it's all a waste of time, work and parts. My impression is that, if not properly configured in the chip, the stock computer will sense the extra fuel pressure, override the variable and set it back to stock pressure.

If the BAP is working with the chip, we should be able to see fuel pressure rise and fall dynamically as we turn the knob on the BAP. No one is seeing those results.
 

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The BAP will not increasure the fuel pressure by itself, the computer will sense the increase in volume/pressure and adjust it to the stock setting unless the computer program tells it to increse the fuel pressure. The BAP will supply the additional volume of fuel to supply the incressure in fuel pressure.

AMB
 

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Re: Re: KB BAP

HAMMER said:
Thanks for the input, AMB but I am confused. If the BAP is properly installed, then we can safely conclude that, when it is turned on, it is supplying extra voltage to the fuel pump, effectively making it work harder and supplying extra GPH of fuel.

But if the chip is not programed to ALLOW that extra fuel pump work to affect the engine performance, it's all a waste of time, work and parts. My impression is that, if not properly configured in the chip, the stock computer will sense the extra fuel pressure, override the variable and set it back to stock pressure.

If the BAP is working with the chip, we should be able to see fuel pressure rise and fall dynamically as we turn the knob on the BAP. No one is seeing those results.
Hammer,
Your thinking on the logic is correct. The main reason why the 03's are so mod friendly is in the strategy of the pcm with the returnless system and fuel pumps.

On a returnless system, the pcm strategy will automatically increase the voltage to the pumps, to generate more fuel flow and pressure, when it is needed. This strategy is something that can be tweeked in a chip. If the BAP is increasing the pressure when not needed, the pcm will try and correct it. Without some tuning in a chip, the BAP will not work like it does on an old diaphram system.

Keep in mind, on an old return style system, a BAP will give you the extra flow, because the pcm is essentially out of the loop. With a returnless system, the pcm is always looking at the pressure and voltage to the pumps to determine the correct voltage. That is the reason why a returnless system uses a fuel pressure transducer, instead of a fuel pressure regulator, as most people are familiar with.

I am not saying that a BAP will not work on an 03, it just takes the proper tuning and programming in a chip to get it to work correctly.

On another note, IMO, I think people see failures of the fuel pressure transducer because of that extra pressure. It would be interesting to know what pressure the transducer can handle before failing. Sorry for the long note.
 

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ok..... on dyno...at 17 psi...my fuel pressure showed 57-58 with the BAP turned to max...i guess my question is.. would that same 57-58 lbs of fuel pressure be there if the BAP wasnt hooked up...cause the BAP is putting out 17.9 volts at full boost..i checked it so the hobbs switch is working and the BAP is increasing voltage...is it increasing pressure at all??
 

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boost a pump...

On the cars i setup with 55lb. injectors, running 17lbs. on pump gas, i don't need to run the boost-a-pump, 0 detonation.....:D
 

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mike5876 said:
ok..... on dyno...at 17 psi...my fuel pressure showed 57-58 with the BAP turned to max...i guess my question is.. would that same 57-58 lbs of fuel pressure be there if the BAP wasnt hooked up...cause the BAP is putting out 17.9 volts at full boost..i checked it so the hobbs switch is working and the BAP is increasing voltage...is it increasing pressure at all??
My car on the dyno, with 17psi, is showing more fuel pressure than that (you should get the number up, it's too low for WOT) and that's without the BAP.

It's not working, Mike. Your stock computer is not allowing the fuel pressure to go up. All you are doing is zapping the fuel pumps without getting any benefit from them.
 

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Hammer , I take care of the fuel thing in the chip, I hold press. @ 68lbs ,
nitro got the combo !
 

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If you folks would indulge me in giving my two cents worth:

1. Delta_P (difference between pressure at pump inlet & outlet) and flow rate are inversely proportional. At a given fuel pump duty-cycle (or drive voltage) a fuel pump can pump X gph of fuel into Y output pressure (given atmospheric inlet pressure). If you increase Y, X will decrease and vica-versa.

2. The PCM strategy is to keep a fixed differential pressure across the fuel injectors so that it *knows* what the injector flow rate is and therefore what duty-cycle to apply to the injectors to get a desired amount of fuel. The FRP sensor is referenced to lower manifold pressure/vacuum so that as boost increases, the fuel rail pressure increases linearly. For example, at 0psi of boost pressure, and a desired fuel injector delta_p of 40psi, the fuel pump will be pumping into a head pressure of 40psi. Now, make 20 psi of boost and in order to keep the rail pressure 40psi above lower manifold pressure, the fuel pump will see 60psi at it's output. Since the output pressure has gone up by 50%, the total flow capability of the pump will drop by roughly 18.5%.

3. In order to get more flow from the stock injectors, one can increase the Delta_P across them. For example, let's say at 20psi of boost on the stock fuel injectors we determine that we need to run them at 70psi in order to get enough flow from them. This means that the fuel pump output pressure will be 90psi. The total flow capability of the pump will drop by 27.5% (as compared to the stock 40psi). So, there is always a trade off between injector flow/pressure and pump flow/pressure. Now, how can we get more injector flow without losing fuel pump flow capacity? Enter the Boost-a-pump.....

The Boost-a-pump effectively increases the total available drive voltage to the fuel pump when the manifold pressure exceeds 3psi (pressure switch activated). By overdriving the fuel pump, we get extra flow capacity at a fixed pressure at the expense of more heat and possibly shorter operating life. Now, a Boost-a-pump MUST be used with a chip. Why? Two reasons:

First, the PCM uses what it thinks is the supply voltage to the pump (battery voltage), the pump flow characteristics (at that specified voltage), and the feedback from the FRP sensor to maintain a fixed fuel pressure. If you turn up the power supply voltage to the fuel pump without telling the PCM, you will mess up the dynamics of the closed-loop fuel pressure control strategy (not to be mistake for the closed-loop air/fuel control strategy) There very well may be driveability issues associated with this as the fuel pressure will have a lot of overshoot/undershoot (error) and it will be difficult for the PCM to control pressure and consequently AIR/FUEL when the BAP is active!

Second and even more important, if the PCMs target fuel pressure at WOT is not increased, the PCM will cut the pump duty-cycle exactly the amount to negate the BAP's increase in rail voltage.

For example, if you were to measure the rail pressure making 17psi of boost it would read 57psi (approx.) given the PCMs target of 40psi injector_delta_p. Now, if you turn up the BAP to max (50%) without giving the PCM a new target, it will cut the FPDM duty cycle by 50% in order to maintain the same pressure. So, the only change that will occur is screwing with the dynamics of the pressure control loop.


A number of people have asked us what the difference between the BAP and our eFPC is so I thought that I'd add this:

4. Our product, the Afterburner-eFPC works in conjunction with the PCM in order to raise or lower fuel pressure in 400rpm increments at WOT. This system intercepts the FRP sensor signal (as well as the TPS and RPM signals) and modifies it in order to force the *PCM* to alter pressure. Although this allows the user to increase Injector Delta_P, it CAN NOT increase the total flow capacity of the fuel pump. The eFPC allows one to precisely raise or lower injector pressure within the PCM's closed-loop fuel pressure control loop. The PCM reacts to the eFPC's input by changing fuel pump pressure by altering the duty cycle to it via the FPDM. However, at full duty-cycle (100%) the PCM can only apply battery voltage to the pump so the flow rate is limited. This is the fundamental difference between the eFPC and the BAP.

The BAP increases the power supply to the pump so it effectively allows the PCM to overdrive the pump to get more flow at any given pressure. One really cool product would be an integration of the BAP and eFPC......maybe I should call Jim Bell about this? ;)

5. After a ton of work investigating the '03's fuel system, I have found that one must be VERY CAREFUL when messing with fuel pressure as the control loop in the PCM is *SLOW* and unless the dynamics are properly tuned, there will be driveability issues when making large changes in fuel demand (i.e. between shifts at WOT, etc.)

There's more to it but this is a basic overview, FWIW.

MJ
 

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AMB said:
Ford Chip/JMS Chip Corp. (Diablo Revolutiom) Chip.
JMS does not use anything DiabloSport. From my understanding he's not even affiliated with Ford Chip. Are you talking about www.fordchip.com or www.jmschip.com ??? Hmmm...

Also, KB uses the DiabloSport Revolution chips made by DiabloSport's parent company, Programa, which essentially is the same as a Deltachip.
 
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