In conjunction with our chips, we developed the Boost-A-Pump to safely increase the work of the stock pump to deliver up to 50% more fuel. Note how the pressure begins to drop off at higher RPM in FIG 1. as well as voltage delivery to the pump (these are directly related to flow). Look at FIG 2. to see the effect of fuel delivery with the Boost-A-Pump. Note how 100% Duty Cycle is never reached. Beautiful! The pump works much less and outputs much more fuel.

 

BOOST-A-PUMP FACTS - It’s All About Pain, Time and Money.

MYTH: "THE BOOST-A-PUMP ISN’T RELIABLE"

FACT: We have thousands of these units in the field working flawlessly, without a single failure that was not due to an installation error. They have been implemented in virtually all of our kits and have been in use daily traveling hundreds of thousands of miles since 1996.

MYTH: "WE CAN JUST INSTALL BIGGER PUMP(S)"

FACT: Shops make money by installing extras. They do not make money when installing the Boost-A-Pump because it’s included in the kit installation price. That’s a lot of extra time (and your money) to install bigger pumps in the tank when it’s not necessary.

MYTH: "WE CAN TUNE IT - DON’T USE THEIR CHIP"

FACT: Shops make money by "tuning". Some do not realize they can’t make it work without the Boost-A-Pump and our chip together.

MYTH: "THAT EXTRA VOLTAGE WILL HURT YOUR PUMP"

FACT: The installation of our Boost-A-Pump will actually increase pump life by reducing its workload. BTW: the Boost-A-Pump only increases the voltage when required under boost conditions. It is a passive system otherwise.

We want to make sure everyone understands: you can install bigger pumps and get basically the same result, but why? It’s absolutely unnecessary and it’s painful, time consuming and will cost more. Also, our intention is not to "knock" people who are out there trying to make a living at installing aftermarket products or providing tuning services. This message is a service directly to our customers to aid them in making the right decisions which way to go when installing Kenne Bell Superchargers.

Thanks.

Kenne Bell

 

Um, did he stop by your house or something dood? Damn nice info! and well put together!

 

Good info.

 

I know I will get flamed for this but oh well here goes.

MYTH: "THAT EXTRA VOLTAGE WILL HURT YOUR PUMP"

FACT: The installation of our Boost-A-Pump will actually increase pump life by reducing its workload. BTW: the Boost-A-Pump only increases the voltage when required under boost conditions. It is a passive system otherwise.

I'm curious. Is the fuel pump a brushless DC Motor or AC motor (only reason I ask is because you are pulsing DC)? Or does it have brushes and is sealed? And what voltage is it rated at? Because the way you got your pressure increase was by pulsing it at a higher voltage, and if you are exceeding the voltage rating of the windings you are going to burn them up eventually even if your pulse width is shorter. A fuel pump with 25% more capacity @ rated voltage and pulse width would be more reliable than an overdriven stock pump, just as the autorotor compressor unit is more reliable as it can flow more air per revolution than the eaton. I am not knocking your product because I am sure you have done your reasearch on what voltages it can withstand, however I am just throwing out my ideas.

We want to make sure everyone understands: you can install bigger pumps and get basically the same result, but why? It's absolutely unnecessary and it's painful, time consuming and will cost more. Also, our intention is not to "knock" people who are out there trying to make a living at installing aftermarket products or providing tuning services. This message is a service directly to our customers to aid them in making the right decisions which way to go when installing Kenne Bell Superchargers.

Thanks.

Kenne Bell

Focus pumps sell for $83 a piece I believe your Boost-A-Pump sells for $199 - $249. I am not seeing the price advantage since I do all my work myself. And your dual program Custom flip chip upgrade is $399 as listed on your price list. Where I can have it done at a reputable tuner once I have my pumps in the same price. So I guess I just disagree with you.

However the knowledge of how the fuel sytem works is very valuable and helpful. Once again I am not knocking anyone's system. Just stating my opinion.

 

Hammer,

Great info, thanks for posting it! Jim has simplified the operation of our fuel systems and issues so even I can begin to understand them. Thats an accomplishment!

Mustang500hp - you shouldn't fear being flamed, your questions are also valid and worth asking.

I would have gone with the BAP/KB Chip if there had been reports of success with that combo. Unfortunately, there weren't many here.

Bill

 

Thanks for the great info. The problem is that the KB chip does not work on all Cobras and KB has done little about it. I went with a full KB set up just as Jim Belle suggests. I thought that would be best. KB blower, KB chip and BAP. Their chip will not operate in my car. I sent the chip back and they said nothing was wrong and sent me a new one. Guess what? Same issue. The car would not run at idle until it went through a 3-5 minute cycle of searching for the idle, from 500 to 2000. It then would run great until you turn the ignition off. When you restart, it goes through the same cycle for 3 to 5 minutes rendering the car undrivable until it goes through the cycle. I spoke to Jim personally and the standard answer was "You have a vac leak somewhere, Oh, your headers are leaking". "It must be something else it can't be our tune. NOT! My companies mechanics went through every mechanical and electrical trouble shooting protocol and test that KB suggested. They all were in the specs provided by KB. No vac leaks, all 02 reading tits on etc etc. Jim Belle then says "Send the chip back, there is nothing wrong, we will give you your money back".

What is interesting is that when I install a Diablo chip tuned by HP by Herman, the car runs great. On the dyno it pulled a 572rwhp, 17pounds of boost, 12.5 A/F ratio with an Auto Tap recording of 35-40psi through out the pull. Add the manifold pressure at boost and you are over 5 psi. continously. I had my KB Boost A Pump at 10%. Just for S**ts and Grins, I also installed my old Diablo/Amazon chip for my previous Eaton mods and it idled perfectly and ran smooth. I never got on it with that chip because it was not tuned for the KB. On the road the AutoTap records excellent fuel presure with the HP by Herman tune through out the rpm and load range.

There is no question that Jim Belle is a smart man. However, I don't think that his programmer has the programs dialed in to accomodate all of the different factory computer flashes . In addition I think their customer service sucks. There are several others that have experinced the same poor customer service from KB. When I was having problems with the chip it was like pulling teeth to get them to help. The one tech told me that I could not send back the chip, without sending back the entire blower package. What a joke. I greatly appreciate Jim sharing his knowledge, but now I think he should back it up by taking care of the legitimate problems that many of us are experiencing with his tunes, so that we can have a total KB package as he suggests.

 

I would have gone with the BAP/KB Chip if there had been reports of success with that combo. Unfortunately, there weren't many here.

Bill

The scrutiny is welcome and that's what the site is all about. Jim Bell is a good friend to me and has asked me to post this information. Johnny Lightning does the same for him on other sites.

I agree with you, Bill. There aren't many people that have talked about the BAP and very fiew understand how it works. From talking to Jim Bell it is my understanding that most customers buy it, take it's worth at face value and utilize it in their cars. They're not sure what it's doing but it's there. Well, that's a SMART CHOICE IMO.

Furthermore, I've seen promenant tuners and racers actually brag about their tune using no BAP, as if it's a trophy and a good thing. Well, it's no trophy - it's simply ignorance, it's a mistake and it's DANGEROUS! You CAN NOT increase pump voltage with a chip. The mechanical value of the BAP can not be substituted in a tune...no matter how creative the tuner is.

Also I am noticing that the high HP cars with injured motors are typically NOT using the BAP. That's because the stock fuel pumps max out at about 600 RWHP without assistance. This is not my opinion, this is fact. MJ datalogged my car and the pumps were at 100% duty cycle at that power level.

After MJ had datalogged my car, I had a full understanding of what the BAP does. It does not change A/F and it does not change fuel pressure (Delta P across the injectors). It merely energizes the pumps so that they act as larger pumps.

The datalog test consisted of monitoring "% pump duty cycle" with and without the BAP. Without it and at idle, the % duty cycle was at 18%. With a slight turn of the BAP knob, it went down to 3-4%.

The BAP is independant of tune and does it's job mechanically regardless of who's chip is in the car. I've heard many people say that they don't think that the BAP is working...because they can't see any signs or 'symptoms' as they turn the knob. Well, the variable that is working..and is generally transparent to tuners and gear heads is the % pump duty cycle...nothing else. But changing that one little variable is enough to save an engine under heavy load and high HP. Use whatever chip you want but keep that BAP running!!

With my car at near 700RWHP, a dyno pull shows that pump runs out at about 5,000 RPMs and A/F then goes straight up. NO PUMP LEFT!! But by turning the BAP on, the stock pumps supply fuel at that power fine...no change in A/F, no change in fuel pressure.

As Jim stated in his message, upgrading to larger pumps is a good idea...it does the trick. But here's my personal feeling: I know that my stock pumps are good. I've got 10,000 miles on my car, about 9,000 of which are with over 600 RWHP and using the BAP. If I upgrade pumps, I run the risk of getting a defective pump that could fail under normal operations. And if I don't notice the drop in fuel pressure RIGHT AWAY, it could melt my engine. The BAP does the SAME THING as upgraded fuel pumps do. So then the question is, does the BAP fry the fuel pumps over time?

Well, I have heard some people claim that it will but there's never technical references to back it up. It's usually just Internet Experts whose claims aren't worth the bad breath that they're printed on...as per usual.

Jim Bell makes very strong claims about the BAP being safe and I find it hard to believe that he's "out in left field" on the subject. He's done all of his R&D with the pump manufacturers and a voltage zap on a variable-voltage returnless-style fuel pump is safe.

I think that if the BAPs generally deteriorated fuel pumps over time, it would have come back on KB by now and they'd stop selling them before they went out of business. If the NORM was for the pumps to fry over time with BAP usage, we'd all be aware of it with no ambiguity because there'd be TONS of info on the net. Instead, I believe that the NORM is for the BAP to be safe and there's a few exceptions to the rule...probably pumps that would have failed due to defects with our without the BAP.

In any event...I am using the BAP with the stock fuel pumps. I have been since the beginning. I will continue this setup in the spirit of the old adage, "IF IT WORKS, DONT FIX IT". I can attest to the BAP working with just about 700 RWHP and safe fuel delivery.

While it may appear that I am pushing a favorite vendor, the fact is that this vendor is one of my favorites because his products actually work as claimed. I'll always advocate what works.

 

Is it time for this datalog graph again. 19lb boost 84% duty cycle with BAP maxed. As you approach the 650HP benchmark the BAP will handle it ! I do think though if DUty cycles go over 90% you need more margin at that power level. Don't know what that margin is ? But if I up the boost over 21lbs with BAP maxed @ WOT, I am seeing Duty Cycles approaching 96-100% . Just my .02 cents worth.

Jon L

 

Is it time for this datalog graph again. 19lb boost 84% duty cycle with BAP maxed. As you approach the 650HP benchmark the BAP will handle it ! I do think though if DUty cycles go over 90% you need more margin at that power level. Don't know what that margin is ? But if I up the boost over 21lbs with BAP maxed @ WOT, I am seeing Duty Cycles approaching 96-100% . Just my .02 cents worth.

Jon L

I'm sure that you're right on the money, Jon. I bet that max BAP and 680-700 RWHP is about the ceiling...and RISKY!

But it DOES prove that the BAP works...does it's job.

Thanks for the info, your posts are always valuable. You need to post more often!

 

Weather the BAP is needed or not, I beleive as does MJ that its added overhead and peice of mind is worth the extra 30 minutes to install it. Even if the tune doesnt force extra fuel pressure, with the BAP installed you have extra voltage available to drive the pumps if need be.

My biggest gripe about the KB chip is we cant disable TC, rear O2's etc.

 

Thanks :hammer . Does the BAP pose any particular difficulties to chip tuners other than KB?

Bill

 

Thanks :hammer . Does the BAP pose any particular difficulties to chip tuners other than KB?

Bill

Bill, it is my understanding (I'm 99% sure of this) that the BAP has nothing to do with any chip, any tune. It's completely independant and that's the beauty of it. It's just an insurance policy for the 'high rollers'.

:beer

Of course, Mr. Lund now has my wheels turning on those damn Focus pumps. It would probably be prudent to use those with the BAP. Nothing like changing your mind and contradicting yourself 3 posts later (meaning me). Oh well, that's what the board is for...so we educate and help each other. Thanks for the enlightenment, Jon.

I'll subscribe to Jon's (Dustoff's) post: If you're not going to exceed 650 RWHP, BAP and stock fuel pumps are safe and sound...but I wouldn't go beyond it.

 

Well, I'm glad that Jim Bell finally posted some information regarding the BAP's operation. In preparation for some BIG boost early next year, I'm possibly going to be installing bigger fuel pumps AND guess what....the BAP. Why? Simple, for extra safety margin and peace of mind.

Jim, if I may, I'd like to clarify one point. I get a lot of people who call me and try to tell me that it's bad for the pumps to be overdriven for extended periods of time. Many people who I speak to don't understand jack about the electronic returnless fuel system and therefore try to apply what they know about return-style systems when thinking about the BAPs operation.

Here's what I tell them:

1. The average voltage to the fuel pumps is the buss voltage (12V nominally) multiplied by the duty-cycle in %. So, 12V * 100% = 12V just like 18V * 66.66% = 12V.

2. When the car goes into boost and the Hobb's switch closes, the BAP turns up the *buss* voltage to whatever it's programmed to. At that instant, if the fuel demand is unchanged, the PCM pulls back duty-cycle to maintain the same average voltage on the pumps. This is done because the PCM closes the loop on pressure. It will do whatever it needs to do to maintain its programmed pressure provided that it CAN raise or lower the duty-cycle. In this case, the load on the fuel pumps has not changed and the electrical power put into the pumps is approximately the same as it was before the BAP came into operation. In this case, the pumps are not being overdriven at all.

3. Let's say that the BAP is set to 50% boost. (the buss voltage is 18V) and the duty-cycle is 66.67% with the pressure switch activated (average voltage of 12V). Now, if fuel demand goes up beyond what can be supplied by the pumps running at 12V average, the PCM can raise the duty-cycle to increase the average winding voltage. This CAN NOT be done with a chip alone. You need the voltage boost converter (BAP) to do it. In this case, the pumps are being overdriven.

4. You can get the same effect with new pumps and honestly, I'd prefer to do it that way. However, until larger pumps are readily available and PROVEN to work in our application (and work for extended periods of time....i.e. longevity) I'm going to use the BAP. In fact, even if I install larger pumps, I'm still going to retain the BAP for extra margin.

5. An ancillary benefit of using the BAP is it will continue to boost voltage despite variations in input voltage which would normally have direct impact on fuel flow capacity. IOW, lose your alternator and have the buss voltage drop from 12 to 10v under load. That's a 17% loss in fuel flow capacity!

My $0.02

MJ

 

But at the same time would you use K.B.'s Chip? I'm not doubting thier BAP..infact i have one...its not installed yet its going in this weekl..but as far as thier tunes...how could you expect the best from them through mail-order you know? it would take twice as long just to get the car running..and then dialed in...even then i would think it wouldnt be at its max potential rather a safer tune...and nobody but KB can touch the chip...thats why 90% of us go with tuners like you did with JDM...now if your tuner knows how to make a BAP function its a different story...some think its shit,some dont...then again some owners dont buy it because they heard its shit and this and that...and go get it tuned w/o.

So really its a combination of things...whether or not the BAP infact does work...well time will tell...like you said cars that failed didnt have it.

Let me ask you this though..

Does JDM recommend the BAP?
Does Strictly Pro recommend the BAP?
Hermann do you use the BAP?

Those are 3 of the big tuners....they get the numbers..and have had success..how do they maintain the fuel system up to par with 600rwhp.

 

5. An ancillary benefit of using the BAP is it will continue to boost voltage despite variations in input voltage which would normally have direct impact on fuel flow capacity. IOW, lose your alternator and have the buss voltage drop from 12 to 10v under load. That's a 17% loss in fuel flow capacity!

My $0.02

MJ

EVERYONE, READ THAT ONE AGAIN.

Even if you are the biggest anti-BAP person in the whole world, just having the ablility to maintain 12V to your pump HAS to be worth it. Even if you don't use any of it's "boost" feature.

 

I talked with my father about overdriving the pump's motors. He's an EE with 45+ yrs experience with motors, gen sets, and large high voltage power systems.

To him, he didn't think it was a big deal at all. The increased voltage *will* wear the pump's motors quicker b/c they are physically doing more work. No way to avoid that. If you pump more fuel, you wear it out faster, BAP or not.

But, the big issue is how long the voltage is raised. On a street car, where 99% of the time the BAP is not increasing voltage above 12V, he thinks there will be little to no difference in fuel pump motor life.

But, if you are a 1/4 at a time guy, and your BAP is boosting voltage 50% of the time the engine is running, that's quite different. You may indeed wear out the pump motor early, and going to larger pumps is the answer. That way, you can get back to the 1% of the time scenario.

What do you guys think?

 

What do you guys think?

I think that I'm putting the focus pumps in my car this week. Like MJ, I'm going to use it in conjunction with the BAP anyway. Thanks to you and your dad for the input.

 

I think you included some good information about BAP. But there are some other fundamentals that I would think that you should address. BAP isn't the best solution. It's just the simplest.

The design of the rail, size of injectors and the pressure and pump flow are all balanced. When you change the pump it will push the other elements out of balanace, some of which can be compensated for through tuning. Drag cars are more forgiving when running at the ragged edge because of the short distances. But you take some of the KB equiped cars and let them run a few laps hard around a track I wonder what the breaking point is.

Here is something that I've come to believe. That the fuel system design is good for 425whp. Even at that it is still lacking. I wish we could get the numbers on the motors that have gone south which cycliders have gone bad etc...

For instance if you are running a 11.8:1 fuel ratio it is often interpreted that we are running that way on all cyclinders. But What I suspect is happening is that we have some cyclinders running rich and some running too lean. Add higher CFM/boost and a heavy right foot on a street car and that's not a good combination.

The forces in the fuel rail contribute to some of the problems. Usually the lower the fuel pressure the lower the shockwave is floating around in the fuel rail. My point for not running around with 80psi fuel system.

Then the design of the fuel delivery in the fuel rail. On a single feed system it is typical to find the injector on the end of the rail flowing more than the one closest to the fuel delivery point of the rail. On our 03's we have a single feed w/ dual rails. So it seems that the cyclinders closest to the firewall are going to be at greater susceptability to irratic delivery. Are they the ones that are going south the quickest? Has anyone run any logged EGT's on those cyclinders above 13psi?

Things to take into account:

1) The forces and their directions and strengths in the fuel rail.
2) The pressure/boost relationship
3) The injector duty cycle
4) Fuel Rail size
5) Type of delivery to the fuel rail. (dual feed per rail = total of four) My understanding behind the theory is that the dual delivery per rail will negate the shockwaves that enter the rail. Because what happens is that as the injector opens and closes the shockwave tends to travel back down the rail. That is why a lot of forced induction cars have fuel dampners. Although I've never seen them advertised as aftermarket. I suspect mainly because the dual feed per rail method is prefereed method of correcting the problem.

I'm not an expert but I have observed these peculiarities when tunning standalones on my WRX and RX7. Since I'm new to SC V8's I'm not speaking as an expert but still think some of my points are valid.

Jim Bell and Ken Christley have been watching the board and the discussions and have asked me to post these comments:

BOOST-A-PUMP THEORY EXPLAINED

There seems to be quite a bit of confusion among tuners and customers regarding fuel requirements for the 2003 Cobra and 2000 up Mustang GT utilizing "returnless" fuel systems when using the Kenne Bell supercharger. We'd like to take a moment to clear up some of this confusion. Since we get a lot of problem call backs specifically from customers who have chosen not to use our chip and/or Boost-A-Pumps with their kits, we feel it necessary to explain more in detail why you should use our complete kits; as we sell them, and use us as the Number One Source of information regarding our kits. Just because someone says they have chip tuning software does not make them an expert at tuning our supercharger kits.

There are a number of reasons why Ford chose to go to returnless fuel systems. One reason of course is cost, another deals with evaporative emissions, loss of octane and quality of fuel, and reducing temperature of the fuel (to help prevent boiling). There are others, but the main focus of this discussion is to assist in pointing out how to increase fuel requirements for elevated horsepower levels when using the Kenne Bell supercharger.

What is not so well understood by many tuners and customers is HOW to deliver the added fuel required. Kenne Bell has performed countless hours developing kits on vehicles using returnless fuel systems (both mechanical and feedback loop) at our dyno facility, on the street and at the track. We use high speed dataloggers and the same air/fuel monitoring equipment the OEMs use to collect reams of data on fuel pressures, flows, mass air flows, pump voltages and duty cycles, and air/fuel ratios to study their relationship with fuel delivery. We know what works. We've done the homework and collected the data.

We possess the in-house ability to fully tune all EECs to make them do what we want when we want.

HOW THE COBRA AND MUSTANG GT RETURNLESS FUEL SYSTEMS WORK

The fuel system is basically made up of the following:

1) Single Fuel Pump (Mustang GT), Dual Fuel Pumps (Cobra)

2) Fuel Pressure Feedback Sensor (both GT and Cobra)

3) EEC Feedback Loop Control

One main principle in delivering the correct amount of fuel relies on feedback from the Fuel Pressure Sensor mounted on the fuel rail. The EEC must monitor fuel pressure constantly and adjust the fuel pump duty cycle in relationship to manifold pressure (more on this later) to deliver the correct amount of fuel. Old return type fuel systems incorporated a mechanical fuel pressure regulator. The old style regulator has been replaced by software in the EEC, fuel pump driver module and fuel pressure sensor. Collectively, they now function as the "regulator".

The important thing often overlooked is that the nozzle outlet pressure of the injector MUST REMAIN CONSTANT against the forces of increasing/decreasing pressure in the manifold. Imagine a door you are trying to keep shut against the wind, but this door has no latch, so it's up to you to keep enough pressure applied to keep it shut as the wind against it increases or decreases. In order to keep the door in the same position, you would have to apply equal force on your side against the wind speed (force) trying to open it.

Now, what if you wanted to allow some air through the door, but you never wanted it to rush in faster or slower. The principle would still be the same as above with one exception: you would have to apply slightly more opposing force to the door at all times to keep the rush of air constant coming in as the wind changed.

Now, an example of what goes on in your manifold: Let's use an easy one. Suppose you have 10 psi boost inside your manifold. The injector (Ford) is rated at 39 psi operating pressure. What fuel pressure do you need to overcome the boost pressure in the manifold?

fuel rail pressure - manifold pressure = nozzle outlet pressure (or delta pressure).

In order to keep the delta (Ford's rated operating pressure) constant (39 psi), the fuel pressure in the rail would HAVE TO BE 49 psi at 10 psi boost, because 49 - 10 = 39.

Now, a not so easy one. If the idle pressure was 30 to 32 psi (typical on most Ford systems), how could you get 39 psi at the nozzle outlet in the manifold? Since the manifold now has vacuum and not boost, how can you produce 39 psi at the nozzle with only 30 psi in the rail?

You can do it because remember the most important thing: it's all about nozzle outlet pressure (delta). Because we read vacuum in inches, it's confusing (who's idea was that anyway?). Write this down: Every 1 psi of atmospheric pressure = 2.036 inches of mercury (Hg). So, if you are sitting there idling at 18 inches (Hg), how many psi would that be?

Inches of Hg / 2.036 = psi or 18 inches Hg / 2.036 = -8.84 psi (ahh, only this is NEGATIVE boost)

In order to keep the delta (Ford's rated operating pressure) constant (39 psi), the fuel pressure in the rail would HAVE TO BE 30 psi at 18 inches vacuum, because 30.12 - -8.84 = 39

(Note, gauges vary a little - if you see ~15 to 16 inches at idle, then you should see ~ 31 to 32 psi in the rail).

Now you know what your fuel pressure should be at all times under all conditions: vacuum or boost! If you have 15 psi boost, then you better have 54 psi in the rail, right? What if the vacuum was 10 inches? Then you better have 34 psi in the rail (10 / 2.036 = -4.91, or 34.09 - -4.91 = 39).

Another way to look at it is vacuum or boost + 39 = desired fuel rail pressure (-4.91 psi + 39 psi = 34.09 psi).

This is where the EEC plays the important role: How does it determine what the fuel pressure in the rail needs to be at all times? The EEC could monitor manifold air pressure (MAP) and adjust the fuel pressure up this way, right? Not without a fuel pressure sensor also. That would cost more to have both. So, Ford does it this way: they already know what the fixed (delta) nozzle pressure must be at all times, right? 39 psi. How could you monitor manifold pressure (MAP) and fuel pressure at the same time with only one sensor? Many people believe the EEC "infers" what MAP is via TPS and mass air flow - NOT! Some people say the fuel pressure sensor also is a MAP sensor - NOT!

The fuel delivery strategy needs only to monitor and adjust fuel pressure as long as a reference to vacuum / boost is applied to the fuel pressure sensor diaphragm! This is how it is done. Remember the door? If the manifold pressure is opposing the pressure from the fuel rail, and the EEC knows to add 39 psi at all time to the feedback pressure, could it be done? YES!

How does the EEC actually control the pressure? By Pulse Width Modulating (PWM) the fuel pump, very similar to how an injector is pulse width modulated. The principle again is fairly simple: build a pump that you know can overcome the maximum fuel delivery requirements of the engine at the maximum pressure and flow rate, then slow the pump down to keep the pressure where you want it during all other conditions. Note: Have you noticed how "slowing down" and "speeding up" pumps has become standard practice on modern fuel systems - just like Kenne Bell, The Innovators has been doing with our Boost-A-Pump. Don't be afraid of this new technology - we've been doing it for over six years.

There's no real magic here: the EEC switches the voltage to ground more rapidly or slowly (duty cycle) dependent upon demand (pressure feedback from the rail sensor). Now for the kicker: Re-read the above paragraph: "...build a pump that you know can overcome the maximum fuel delivery requirements of the engine at the maximum pressure and flow rate..." Hmm... we added 50%+ more power and guess what? The pump isn't going to make it even at the fastest duty cycle. We'd like to show what happens to the pump PRESSURE and VOLTAGE once you've reached 100% duty cycle and the EEC wants to deliver more fuel, but it CAN'T (see FIG 1).

The interesting thing here is many tuners think they can "play with" the pressure or raise the duty cycle. NOPE. Once you're at 100% folks, that's it. You only have two choices: 1) increase the existing pump's output (flow) at the same given pressure or 2) install a bigger pump. BTW: merely increasing a pump's pressure DOES NOT , WILL NOT, CANNOT INCREASE ITS OUTPUT IN FLOW.

Another humorous one is "We'll just put some bigger injectors in. That'll fix 'er". NOPE. The pump is DONE, FINITO, KAPUT. Installing bigger injectors doth not maketh thy pump bigger.

Now, if you are Kenne Bell, you have the best of all worlds. We can install the Boost-A-Pump and allow the pump to operate much more efficiently, output more flow at the same pressure as before (up to 50%) AND then install bigger injectors, AND control the pump duty cycle with our chip!

Without the Boost-A-Pump, bigger injectors and increasing the pump duty cycle is not an option provided the pump was already at 100% duty cycle at WOT.

 

I think that I'm putting the focus pumps in my car this week. Like MJ, I'm going to use it in conjunction with the BAP anyway. Thanks to you and your dad for the input.

I am thinking mine are already ordered..... HEHEHEH ! I agree 100% Rich if you want more overhead assurance at our HP level have both !!!

By the way Rich are you coming to Super Stallion Event at Cecil on 8 Nov. ?? I hope to see ya there Bro !!

Jon L

 

Someone out there simply needs to make a complete kit for the fuel system. It makes no sense why people are spending 5 or 6 thousand dollars on tuning and Kb alone? I don't have much money for an upgraded fuel system but if I'm going to be running my Cobra with 600 plus horsepower wouldn't I have to spend that extra money? To me everyone is trying to make these big horsepower numbers using the stock injectors, stock pumps, adding BAP, stock rails, etc but why?

The BAP is really something not to mess with my opinion. Increasing more fuel from a pump that is already giving out all it can makes no sense to me. Its almost like boosting 25 pounds out of an eaton blower. Sure a company can make pulleys and force the blower into a new level of performance but what does that do to the blower? Just like the BAP, sure it can make the pumps work harder but in the long run what happens? The pumps give out. Not very safe to be forcing the fuel pumps to work so hard.

Do I make any sense here?

 

I talked with my father about overdriving the pump's motors. He's an EE with 45+ yrs experience with motors, gen sets, and large high voltage power systems.

To him, he didn't think it was a big deal at all. The increased voltage *will* wear the pump's motors quicker b/c they are physically doing more work. No way to avoid that. If you pump more fuel, you wear it out faster, BAP or not.

But, the big issue is how long the voltage is raised. On a street car, where 99% of the time the BAP is not increasing voltage above 12V, he thinks there will be little to no difference in fuel pump motor life.

But, if you are a 1/4 at a time guy, and your BAP is boosting voltage 50% of the time the engine is running, that's quite different. You may indeed wear out the pump motor early, and going to larger pumps is the answer. That way, you can get back to the 1% of the time scenario.

What do you guys think?

My point exactly That the correct and properly engineered way to do things is to use a larger pump for people that spend a lot of time at WOT. As MJchip said 18V @66.66% duty cycle = 12v. However if you look at the graph hammer posted you will see that the duty cycle is well above 66.66% with the boost a pump above 4300 rpm. Which I understand has to be done to get the increased flow out of the fuel pump, but the correct way would be to use a larger pump that was designed to flow that level within its rated voltage. I can understand wanting insurance but with the larger pumps it shouldn't be needed, and I wouldn't make it common practice to run the fuel pump much over 14 volts, anyway.

About the alternator dropping thing and the boost a pump saving your fuel pressure I hate to tell you that power doesn't come from no where and the boost a pump is not a generator, therefore if you had it set to say 17volts with an input of 14 volts and your input voltage drops to 10 then your output is going to drop to around 12. which would not save you at all if your engine is tuned to use the 17 volt supply. But it is kind of erroneus anyway because anyone getting in boost when the battery voltage is @ 10 volts needs their head examined as it is very noticable there is something wrong @ that voltage.

 

Someone out there simply needs to make a complete kit for the fuel system. It makes no sense why people are spending 5 or 6 thousand dollars on tuning and Kb alone? I don't have much money for an upgraded fuel system but if I'm going to be running my Cobra with 600 plus horsepower wouldn't I have to spend that extra money? To me everyone is trying to make these big horsepower numbers using the stock injectors, stock pumps, adding BAP, stock rails, etc but why?

The BAP is really something not to mess with my opinion. Increasing more fuel from a pump that is already giving out all it can makes no sense to me. Its almost like boosting 25 pounds out of an eaton blower. Sure a company can make pulleys and force the blower into a new level of performance but what does that do to the blower? Just like the BAP, sure it can make the pumps work harder but in the long run what happens? The pumps give out. Not very safe to be forcing the fuel pumps to work so hard.

Do I make any sense here?

You sure make sense to me. I do not understand for the life of me why everyone is so hung up on this returnless system when making those kind of numbers!!!!!!!

The cars making 600 hp need a dedicated fuel system. From the pump (pumps) all the way to the fuel rails and injectors. I personally feel you need to go to a return style system. MHO

Just for the record...I was using the BAP on my 98 Cobra long before it became popular. My theory and my tuners was it provided CONSISTENT voltage to my Bosch 390 pump. Seemed to work well for me, and never had any failures or issues.

Ben Dorn

 

About the alternator dropping thing and the boost a pump saving your fuel pressure I hate to tell you that power doesn't come from no where and the boost a pump is not a generator, therefore if you had it set to say 17volts with an input of 14 volts and your input voltage drops to 10 then your output is going to drop to around 12. which would not save you at all if your engine is tuned to use the 17 volt supply. But it is kind of erroneus anyway because anyone getting in boost when the battery voltage is @ 10 volts needs their head examined as it is very noticable there is something wrong @ that voltage.

You sound like an EE but you are assuming a given type of straight boost converter. Ever hear of a SEPIC converter or have you ever built a simpler regulated supply whose mission it was to put out a fixed output voltage over a wide input voltage range that spanned (above and below) your desired output?

For example, take 8-18V DC input, feed it into a x2 boost converter and regulate down to 12V. Piece of cake either way. No magic, no smoke and mirrors, no perpetual motion or energy generation.

MJ :evil

P.S. Not sure if this is the converter topology used in the KB BAP but now you have me intrigued. I'm going to test this to see what type of converter it is.....unless Jim Bell wants to chime in and save me some work.

 

Someone out there simply needs to make a complete kit for the fuel system. It makes no sense why people are spending 5 or 6 thousand dollars on tuning and Kb alone? I don't have much money for an upgraded fuel system but if I'm going to be running my Cobra with 600 plus horsepower wouldn't I have to spend that extra money? To me everyone is trying to make these big horsepower numbers using the stock injectors, stock pumps, adding BAP, stock rails, etc but why?

The BAP is really something not to mess with my opinion. Increasing more fuel from a pump that is already giving out all it can makes no sense to me. Its almost like boosting 25 pounds out of an eaton blower. Sure a company can make pulleys and force the blower into a new level of performance but what does that do to the blower? Just like the BAP, sure it can make the pumps work harder but in the long run what happens? The pumps give out. Not very safe to be forcing the fuel pumps to work so hard.

Do I make any sense here?

No !!! Go back and reread the Jim Bell Post from Hammer.

This product (Boost-a-Pump) has been out for sometime. There are even Manufactors that have copied the design. The BAP does exactly what it was designed to do when installed and used correctly. If there was a Huge failure rate in the Market for the Boost-a-Pump killing the Pumps then I think we would have heard about it. How many 2003 Cobras have had Fuel Pump failures resulting from overspeeding the Pumps ?? The BAP has been used on Lightning trucks since 99, GN Buciks in the early 90s and numerous other autos. You are comparing an Eaton Blower being overspun to a an electric fuel pump being over-voltaged. Not a very good or even close comparison IMO. It is not a band aide fix ! It is an alternative solution just like installing Focus Fuel Pumps. I plan on installing Focus Pumps and using the BAP also. Sorry if I sound determined ! I am just tired of reiterating the same BAP info over and over...

BTW in the long Run ! If you have a BAP working correctly I feel you will still have an 03 Motor working with all 8 slugs correctly.

Have there been any 03 Cobra motors blown with a BAP installed and working during the failure ??? Speak Up if so !!!!

Jon L