i have run a Kenne Bell Boost A Pump since 2004. i find it an easy way to solve the fuel flow challenge of our thirsty motors. especially nice as it only juices the pump while in boost.

given the rotary needs about 30% more air to make similar output to a piston motor, it also needs 30% more fuel. in addition, it needs to run on the rich side at higher power levels and then there's E85 which requires 30 to 40% more fuel.

there are many ways to get it done and most work. you can do multiple pumps, or one monster pump or swap in what is currently the best 21st century single intank pump, the Walbro 9000262 (gas) or 9000267 (E85).

if you are approaching 600 rw on E85 the Walbro may be marginal.

at 13.5 V the pump makes 389 L/H

at 16.0 it makes 568!!!!!!! more than enough for more than 600 on E85.

at 16 V the pump is happy BTW.

of course life can't be that simple. Kenne Bell just changed their BAP to a 17 V minimum... which is too much for the pump.


/////////update: the 13.5 V base model is back by popular demand, see post 11 in this thread/////////////////

other than an FYI on this i would like to ask the board, someone who knows electricity better than me...

would it be feasible to run the BAP at 17 V and add some sort of resistor so as to end up at 16.0? if so please add the specifics.

thanks,

Howard

 

how do you know 17V is too much? whats another volt.. but if you did want to drop to 16V with a resistor, you would need 0.05 ohm, 30W resistor

 

"how do you know 17V is too much? whats another volt.."

i talked to Jim Bell @Kenne Bell and they determined on their flow bench.

thanks for the help. now that i think about it, the resistor would have to be in series and it would be lowering the V when not in boost. that might not be a deal breaker.

i do have the older BAP unit so this doesn't concern me, i am just thinking about others.

HC

 

The MSD Pump Booster is now programmable with a PC to add from 1.5V to 22V! I have an older non-programmable version that's been doing duty on my Bosch 044 for many years. I think it's a viable option to the Kenne Bell.

 

Sure. The fundamental relationships you are looking for are goverened by Ohm's Law. First you need to estimate the expected current (I) @ 16V and Let's say you want to drop the voltage 1 volt. You would divide the desired voltage drop (1V) by the pump's current, estimated at 20A. Your result is 0.05 ohms (commonly denoted by the Greek letter Omega). You will also need to determine the power dissipation in the resistor, which can be determined with this formula: I squared * R. So the product of the resistance multiplied by the pump current squared. Or 20 watts. This is quite a bit so you'll want to pay attention to where the resistor(s) is mounted. I suggest using (2) 0.1 ohm/50watt resistors in parallel to achieve the required resistance without getting too hot. Hope this helps get you started.

 

thanks gxl90rx7, elwood and Speed of Light for your help.

again let me make the point re VOLTAGE.

Walbro E85 pump 900267

13.5 V 389 Liters per hour

16 V 568 Liters per Hour

an 18% increase in volts =s 46% increase in fuel flow at 60 PIS.

as per Jim Bell/Kenne Bell/ fuel flow bench.

since both the Kenne Bell and the MSD unit (thanks gxl90rx7) work only in boost you don't get the over recycling of fuel which does tend to add heat.

combine either product w the newer Walbro intank pump and most have fuel needs covered.

i looked at both the Kenne Bell Boost A Pump (BAP) and the MSD product in 2004 and decided in favor the the BAP. unlike the MSD unit, the BAP has a separate boost solenoid that situates in the engine compartment. you will see it in the plastic bag. since it is very small it is a non factor spacewise in a typically cluttered engine compartment. since it sends a signal (boost) to the module via two small wires it allows the command module to situate where it belongs, near the battery (pass side rear compartment) and near the fuel pump.

the MSD unit has the boost solenoid within the module so it must be in the engine compartment. that means if your battery is in the rear you will need to run significant sized wires up to the engine compartment and then all the way back to the pump.

the current drawback is the BAP now has a 17 volt floor which doesn't work w the new Walbro pumps according to KB.

the fix is to use a resistor to step down the output or go w the MSD setup.



the MSD unit was recently upgraded and is now Windows based and apparently offers pretty much any Voltage so you don't have to do the resisitor to show the pump 16.0 V.



both units are priced close... BAP is generally available direct from KB at $280 and the MSD unit is $309 on AMZ.

properly fixtured, they take fuel out of the picture.

BTW, i also run KB's Boost A Spark.... adj V to the coil only in boost.

howard

 

I put my MSD pump booster behind my seat, near my battery and fuel pump. I ran the hose from the intake manifold back to the pump booster.

 

These have always seemed to be a poor subsitute for under spec'd fuel pumps to me.

 

is there an automotive fuel pump out there that flows more than 400 lph?

another thing to keep in mind is you want to drop voltage to the pump when cruising around as well. 400lph while idling/cruising does nothing but heat up your fuel. im running a walbro 400 in my FD, wired straight to 12V, but got tired of the noise of the fuel pump going full blast all the time and the fuel boiling in the gas tank after long runs. i went back to using the factory resistor relay, boost-activated via haltech ems.

 

The new walbro claims to flow 450lph

 

Jim Bell of Kenne Bell got back to me yesterday re the BAP turbo rotary app as regarding the new high flowing Walbro pumps.

while they have moved the BAP to a 17 volt minimum output which is too much for the pumps (sustained) he indicated that when ordering a BAP....

ask for Mike.

tell him you want the 13.5 V (base) BAP/HowardColeman turbo Mazda option.

set your pump for just under 20% gain and you will have a happy pump and the output will go from around 390 to 570 L/H at 60 psi.

a simple solution to most fuel supply issues considering the pump is very close to a drop in.

do not forget to switch to a 30 A fuse.

hardwire around the OE connector at the tank.

Howard

 

Is this kind of like getting a star named after you?

 

"Is this kind of like getting a star named after you?"

i thought it was kind of weird and asked him couldn't it just be a 13.5 base option, or turbo rotary option but no. hey, he owns the company and i am just happy the correct model will be available.

hc

 

how does the bosch 044 handle a BAP? any numbers?

 

The output of any of these positive displacement fuel pumps operating in its design range is going to increase or decrease roughly as the square of the change in applied voltage. So let's say you increase the voltage at the pump from 12 to 14 volts--about a 17% increase, there will be a corresponding increase in current and pump output will increase by 1.17 squared or about 36%. This also works in reverse: decreasing the voltage from 14 to 12 volts results in about a 36% decrease in pump flow, assuming a constant output pressure. (I have neglected pump efficiency in this example, however, it will likely remain relatively constant within a narrow range of a couple of volts.)

 

'don't know re Bosch but my Denso Supra pump ran at 16 volts for 5 years with no problems.

howard

 

seen a lot of glowing reviews for the JMS FuelMax from former BAP owners, has a higher price on the base version anyway

the MSD unit is interesting, thanks for mentioning it

 

A lot of BAD reviews for the MSD BAP.

 

if you are on this thread you are interested in fuel system dynamics.

i suggest you read this helpful thread from Kenne Bell:

http://www.kennebell.net/KBWebsite/C...elpumptech.pdf

howard

 

Howard,
Are the stock fuel lines large enough to handle the flow of that pump and boost-a pump set up?

 

I had to shed alot of Inj Ms when going from the stock 5/16 to 6an line above the 450 rwhp mark.

 

Hi Howard, I am having some strange issues with my Kenne Bell BAP.....

Can you look over my setup for any obvious issues;
Kenne Bell 17v , I have relocated my FD's battery to the boot, I run my fuel pump/BAP from an aftermarket 30amp relay, hard wired to the battery and using the fuel pumps stock wire as a trigger all decent 10 gauge/25+amp wiring, the BAP is set to kick in with 10psi boost switch and I put in a 30amp relay in the BAPs inline fuse holder....

it works perfectly and supports my ~500bhp with ease. BUT at low revs/decel/clutch in and out, I can always hear what I am fairly certain is the relay clicking ! (its either the relay of the bap but fairly certain its the relay, at low revs).......

my fuel supply doesnt appear to drop, my widebands values dont change..... its just always clicking every 10 seconds or so when cruising / stopped always seems to be around the time I am coasting at low rpm or am on and off the clutch when pulling upto lights.

Its as if there is some interference or electrical load which is causing issues with the relay. which it should not be doing considering I have it hard wired to the battery sitting with in .5mtr of each other. I even removed the FD's stock 2 speed fuel pump resistor as I thought the trigger wire might be dropping voltage for some reason, but this has not helped. would it have anything to do with electrical load ??

thinking my next steps are upgraded wiring and alternator but I am not convinced this will solve anything.

 

Sure it isn't buggered rear end bushes? They make all kinds of clunks and noises on and off throttle when they have slop in the rear end. Does it do it if you free rev the engine and let it settle with no, some, a bit more throttle with the car stationary?

 

i don't have an answer for you re your problem but...

Kenne Bell recently changed their BAP and now markets a 17 V base model. prior models were 13.5 V.

i have always run my BAP at a 20% V gain, or just under 16V.

while this might not sound like a big deal it is:

Walbro E85 pump PM 9000267

13.5 V 389 Liters per hour at 60 psi

16.0 V 568 Liters per hour at 60 psi

flow numbers come from the Kenne Bell bench. (accurate)

Kenne Bell does not recommend running any of the intank pumps at 17 V. they have experienced pump failures when run continuously (hours) at 17.

zero problems at 16.0 V.

do not use the 17 V model.

the 13.5 V model is still available upon request. call KB, ask for Mike and the 13.5 V model.

Howard

 

hey mate, nah 100% its the relay or KB clicking.

there is no particular pattern unfortunately, it is just always on low load, pre 3000rpm. either when coasting, part throttle, putting the car into neutral whilst still rolling, pulling up it will click a couple times but then sit idling perfect, until i start driving at low load it will click again. I just have a feeling its some kind of interference from something like the clutch switch or the neutral sensor... something like that.

I am going to change out the relay for a higher quality unit and also recrimp and solder all connectors again, just incase. will also jump out of the car whilst ideling and try to see exactly which part is making the noise, it was hard to judge last time and like i said when i pull up it will click a couple times briefly then sit there idleing perfect with no clicking.