boost a pump for KB????????

[raiders03]

boost a pump for KB????????Help

Do you need a boost a pump for your Kenne Bell if you have the Focus fuel pumps and 55 injectors? I have heard conflicting answers.

 

[03Steve]

No.

 

[raiders03]

03Steve
Do u know how much rwhp the focus fuel pumps can handle?

 

[03Steve]

1 million hp.

Randy just put down 698 STD with focus pumps and 55# injectors. But, the fuel demand for the P1SC2 is not as great. And his pumps are maxed out up there.

The focus pumps on a KB car are good to mid to high 600's Get the focus pumps and 55# injectors, then start ditching the 300 hp suspension for 600 hp suspension.

Nothing says I luv you like a 1.3 60' time. :beer:

 

[NMRAcer]

why go with focus pumps? Why not put 2 255lph pumps in there?

 

[03Steve]

Sounds good. There is no special mounting hardware to hold the fuel pumps in.

Just did focus pumps on my bucket last week, lowered the tank just far enough to pull out the assembly. Didn't even disconnect the main fuel fitting from the top (it's a BITCH).

Pigtailed wire, strap to hold on the pumps. Got any pics of 255's NMRA?

 

[mm49]

Originally posted by NMRAcer
why go with focus pumps? Why not put 2 255lph pumps in there?

Because noone makes returnless 255 LPH pumps yet. Focus pumps are the next best (sort of) returnless sytle pump.

A standard walboro 255 lph pump or pumps for a return system will not last long due to the variable voltage PID returnless setup.

The Focus pumps will add approx 20% capacity at best. If you are running the fuel pressure where KB recommends the Focus pumps run out of steam around the 675-700rwhp mark with no margin for error.

 

[NMRAcer]

returnless pump, OK. I never knew there was a huge dif in the pumps. thought itwas just a dif in the way the system was set up.
thanks mm49

 

[03Steve]

So duty cycle kills return style pumps?

 

[JKD COBRA]

eaton - from what I have read, the focus pumps are good for 700rwhp. But I think at that power level the fuel lines become the restricting factor.

Someone please correct me if I have it wrong, but thats what I have seen so far.

 

[03Steve]

I'm not convinced. Who has actually tried it? It is just an internet 03 cobra forum given that return style pumps cannot handle duty cycle?

We need a function generator, a 255 pump, and some good old fashioned test time.

Down with the internet theories. :kaboom:

 

[mm49]

Originally posted by 03Steve
I'm not convinced. Who has actually tried it? It is just an internet 03 cobra forum given that return style pumps cannot handle duty cycle?

We need a function generator, a 255 pump, and some good old fashioned test time.

Down with the internet theories. :kaboom:

There are several individuals that have had 255s in but had pump failure rather quickly. Within days of install. Kenne Bell has done testing also with this setup and the return pump can't handle the voltage flux. I have heard that Bosch makes some OEM Methanol (alternative fuel Pumps) that are rated at 300+ LPH @ 75psi and are returnless PID capatible but I have had no luck turning up any info. Someone has got to step up to the plate with some Big returnless sytle pumps .... Most OEM pumps these days are returnless.

 

[03Steve]

My roommate has a 99 procharged 4V with returnless fuel system. He has one 255 pump. First he used a chicane, now he has a warlboro. The chicane sucked, so he switched to the walboro. No problems, I drive his car and it runs great!

-What tested pumps failed?
-Just one brand?
-All brands?
-How many 255 manufacturers are out there?
-Why not try a pair of the walboros that my roomate's 4V runs?
-Is everyone who has a supercharged 99+ GT or 4V only running SVT focus pumps for upgrades?


There is a better set of pumps out there, that can handle duty cycle. Ask my roommate, or any of the guys who have been supercharging their returnless mustangs for the last five years.

I'm gonna look into the 255 market, and try to find out what will work.

 

[raiders03]

03Steve
I have 255 pumps, i believe they are Focus not sure though. One of my stock pumps was failing and my car was running lean at high rpm's. I had 255 pumps put in. They fixed the problem. Does the boost a pump make it safer incase a fuel pump fails? Does it help prevent the fuel pumps from maxing out making the odds of pump failure less. Sorry for all the questions but I really do not want any failure when I have my KB put on in two days. I will be running the 19 psi pulley and 97 octane if that matters.

 

[03Steve]

I think you are making a good decision for running 97 with 19 psi. Some ppl are taking pump gas a little to far (cough, RANDY, cough).

As far as the BAP goes, I don't like it. I have had nothing but problems with stock pumps and the BAP. Here is an example:

If you drive around with the BAP and give the car a little gas, your car will see a little boost on the boost gauge. If the 3 psi switch used to activate its "voltage boost" on the BAP closes, your fuel system will receive a sudden pressure spike that is directly proportional to the BAP controller's setting. The pressure spike causes the car to jolt, severely in my case because I had my tune with the BAP at 40%.

The higher the controller setting, the harder the jolt. Not fun for driving in sixth gear down the highway.

The concept of the BAP is to "overdrive" your pumps with a step-up DC transformer. The higher you turn the controller, the more voltage & current you are sending to your pumps. This will increase the chance of pump failure in the long term. I am a electrical engineer for a robotics company, I see the long term effect all the time.

Run the right size pumps. If you need a set of 255's (focus pumps are 160's or 190's) get a set of 255's. Do not overdrive your stock pumps with a duct tape transformer.

 

[raiders03]

03Steve
thanks for all your help

 

[mm49]

Originally posted by 03Steve

As far as the BAP goes, I don't like it. I have had nothing but problems with stock pumps and the BAP. Here is an example:

If you drive around with the BAP and give the car a little gas, your car will see a little boost on the boost gauge. If the 3 psi switch used to activate its "voltage boost" on the BAP closes, your fuel system will receive a sudden pressure spike that is directly proportional to the BAP controller's setting. The pressure spike causes the car to jolt, severely in my case because I had my tune with the BAP at 40%.

The higher the controller setting, the harder the jolt. Not fun for driving in sixth gear down the highway.

Several Folks have had this problem ! I had it and wired around the BAPs boost switch but then had the pain of continuing to adjust the knob for the power level or speed I was running.

I eventually went back to an adjustable hobbs switch set at 8psi but adjustable from 6-14psi. This switch set to 8psi fixed the jolt, it works great now. No jerk or jolt at 8psi it engages at the higher boost where more FP and duty cycle is startingto be needed.

This does not address the BAPs long term effect on pump life though. I think you are right Steve some 255 testing is needed !!
There have to be some out there. I also increased the wire diameter from the Fuel Pump Relay to CCRM - FPDM tothe pump. This wire diameter increase gained me a confirmed 1.12voltage increase at the pump before the BAP is even used. I datalogged thie duty cycle before and after an it equated to a 11% duty cycle drop at cruise and about 4% at idle. Every little bit helps.

What is the part # on your friends 97 Cobra Walboro 255 pump installed. They make several 255s maybe one is PID compatible.

Jon L

 

[03Steve]

Good stuff, Dustoff! It is a 99 GT with a 4V swap, I will ask him to post over here for info on his pumps.

 

[mm49]

Cool ! Sorry 99 not 97.... That would be great !

 

[brad65ford]

I can't find the site but somewhere Jim from KB is talking to customers in a forum about this topic. I'm interest in upgrading my stock system for future plans myself, but nothing seems rock hard relieable from what I've read anywhere. Thats the worse thing that could happen IME and I know others, under boost and the fuel cuting out. Boom or melted a piston. I wonder if there is something that can detect when the fuel pressure is lower than it should be and retard spark or something to that effect?