F$%&.....Dual Aviator Pumps Installed...OUT OF FUEL!

[mjchip]

Crap! I just got done installing dual Aviator pumps in my Cobra, turned off the BAP, and went for a WOT pull.

At the dyno the last time I ran the stock pumps with BAP at 50% boost. At 618rwhp SAE the FPDM output was only 74% duty-cycle. Today with the dual Aviators and the BAP disabled the FPDM duty cycle hit 100% at 5,333rpm. The fuel pressure slowly began dropping from commanded 39psi (delta_P) shortly thereafter.

Here is a high-bandwidth datalog that better shows fuel pressure and air/fuel ratio:

I'm wondering if the extra current draw is causing the supply voltage at the FPDM to drop and therefore killing the capacity of this new pump assy. Maybe its time to run some heavy gauge wire out that way.

On a side note, I designed a neat little electronic gizmo that extends the full-scale range of the stock MAF. As you can see from the Excel graph below the same WOT run resulted in a maximum MAF voltage of 4.5V at peak HP around 6500rpm. From the last dyno pull I made this is over 600rwhp.

MJ

 

[vector]

thats very interesting

 

[mjchip]

Originally posted by vector
thats very interesting

In kind of a shitty way no?

MJ

 

[vector]

still waiting on SCT datalogger so i have no way of knowing what mine does


i know the wire job just sucks

damn mj that just blows

damn damn damn

 

[vector]

well one good thing what eevr is limiting you it will not happen to most due to your more modded

on a different note that sucks for me to

are you going to try the rewire first?

 

[mjchip]

Originally posted by vector
still waiting on SCT datalogger so i have no way of knowing what mine does


i know the wire job just sucks

damn mj that just blows

damn damn damn

It blows but something just isn't right. I heard that a single Aviator pump should outflow a stock '03 Cobra dual pump. My results don't seem to support that spec.

I'm confused.

MJ

 

[vector]

posted this on mod fords posting here now for others

one thing i dont understand MJ when they tuned my car they had no trouble comanding MAX a/f all the way to 6700 where the pull stopped

there seemed like there was a ton of pump left

one aviator pump was show on the corral to make just over 500+ on a 99-01 style cobra

with just one pump

so i am a little los tas to whats going on with yours

i wish i knew some one close that could datalog for me

 

[plan b]

How much of a voltage drop are you seeing at the pumps? I thought the aviator pumps flowed better as well. I was going to do pumps during the winter, I guess I'll wait and see what happens.

 

[Emmerson_Biggins]

MJ
Just a thought, but if you have increased current, the voltage should be there. A decrease in current may mandate a larger wire since the wire itself could be hampering electron flow. I am now wondering if the Aviator pumps are flowing as advertised. Thanks for posting your data.

 

[Buster]

Originally posted by mjchip
On a side note, I designed a neat little electronic gizmo that extends the full-scale range of the stock MAF. As you can see from the Excel graph below the same WOT run resulted in a maximum MAF voltage of 4.5V at peak HP around 6500rpm. From the last dyno pull I made this is over 600rwhp.
MJ

Hi MJ

I don't wanta get off topic but are you selling these gizmos? I like to order one if so..

TIA

ML

 

[vector]

one aviator pump is almost = to a walbrow 255

one aviator pump can do over 500 HP on a single pump(a few people in 99-01 cobra's) have used them to repalce there walbrow 255 and are making over 500 hp do a search on the corral for this info

 

[mjchip]

Re: Re: F$%&.....Dual Aviator Pumps Installed...OUT OF FUEL!

Originally posted by Buster
Hi MJ

I don't wanta get off topic but are you selling these gizmos? I like to order one if so..

TIA

ML

Not sure yet. If I sell them A LOT of testing would have to be done first.

MJ

 

[plan b]

I don't really want to go to a return fuel system but for the really high hp cars it is probably the safest way to go. I know it definately isn't the cheapest. MJ you have a bitchin' setup, I'm curious to see what the problem is with the fuel issue.

 

[SoCalSnake]

subscribing

 

[mjchip]

ttt

 

[Wilson & Co]

sorry to hear that dude...Something is def wrong. Is this the same power level you were last at? What did you use to clamp the plastic hose to the pumps? any leaks possible?

While I'm not near the power level you're making(yet The car made 575HP yesterday... I planned for it before with the return setup.

That being said, once I get time I am going to datalog my fuel system to see what's what. The great thing is NO MORE FRPS with a return system! Well from what I can tell so far anyway.

 

[mjchip]

Originally posted by Wilson & Co
sorry to hear that dude...Something is def wrong. Is this the same power level you were last at? What did you use to clamp the plastic hose to the pumps? any leaks possible?

While I'm not near the power level you're making(yet The car made 575HP yesterday... I planned for it before with the return setup.

That being said, once I get time I am going to datalog my fuel system to see what's what. The great thing is NO MORE FRPS with a return system! Well from what I can tell so far anyway.

Hi, I agree something ain't right. This is the same power level. I used very small screw-type hose clamps (stainless steel) and the stock corrugated lines.

Also, I used the Aviator fuel socks which were much bigger than the stock ones.

Congrats on getting the Whipple up and running.

MJ

 

[mm49]

Mark,

Try the wire upgrade ! It is a pain, but I did this last fall and it was worth 1.12 volts at the pumps and it dropped the amperage significantly. I paralleled a 10 gauge wire from the Fuel Pump Relay Fuse - CCRM - FPDM - BAP - Fuel Pump just outside the tank. I also recently did this wiring upgrade on Hammer's (Rich J) Cobra. He was running Focus pumps and now the BAP along with them. Also for what ever reason I have read recently that the fuel pump sock to run is the smaller (short) Focus sock. I too have avaitor pumps and the Visteon Flow sheets to compare the Focus to the Aviator. I stopped the install due to time. I am currently still running the stock pumps with BAP maxed. Thru the lights at [email protected] at 84-86% Duty cycle. So I am hesitant to replace the combo that works so well. That is with 19lbs boost. I think the wiring upgrade will do alot for the Aviator amperage draw and help the situation.
Jon L

Originally posted by mjchip
Hi, I agree something ain't right. This is the same power level. I used very small screw-type hose clamps (stainless steel) and the stock corrugated lines.

Also, I used the Aviator fuel socks which were much bigger than the stock ones.

Congrats on getting the Whipple up and running.

MJ

 

[mjchip]

Originally posted by mm49
Mark,

Try the wire upgrade ! It is a pain, but I did this last fall and it was worth 1.12 volts at the pumps and it dropped the amperage significantly. I paralleled a 10 gauge wire from the Fuel Pump Relay Fuse - CCRM - FPDM - BAP - Fuel Pump just outside the tank. I also recently did this wiring upgrade on Hammer's (Rich J) Cobra. He was running Focus pumps and now the BAP along with them. Also for what ever reason I have read recently that the fuel pump sock to run is the smaller (short) Focus sock. I too have avaitor pumps and the Visteon Flow sheets to compare the Focus to the Aviator. I stopped the install due to time. I am currently still running the stock pumps with BAP maxed. Thru the lights at [email protected] at 84-86% Duty cycle. So I am hesitant to replace the combo that works so well. That is with 19lbs boost. I think the wiring upgrade will do alot for the Aviator amperage draw and help the situation.
Jon L

Jon,

I was hoping that you'd respond. Thanks.

Did you have to remove the interior to do the wiring upgrade? Can you email me the flow sheets for the pumps? Also, if you have any wiring tips and you don't mind can you email those too?[email protected]

To tell you the truth, I was simply trying to get around the hesitation when the BAP kicks in. At 618rwhp with the BAP maxed and stock pumps my FPDM d.c. was only 74% (14psi of boost). Plenty of fuel.

The only other concern I have is this. I have the BAP wired in the circuit, the knob at 50% boost and I simply open-circuited the hobbs switch so that it never activates to run the test. I'm wondering if there is significant voltage drop in both the FPDM and the BAP as well as the wiring. This would substantially cut the available fuel pump capacity.

MJ

 

[DaleM]

MJ,
You bet I'm following this one.