Any body using the red Aeromotive pump on blown EFi applications? Pressure was dropping off on the Dyno with the dyno's Red Aeromotive pump. Pressure starting dropping at 4500RPM and was critically dropping at 5500 RPM. Boost reference vacuum line was connected. Engine was making pretty big power at 5500 RPM

Irrespective of the condition of the dyno shop's red Aeromotive fuel pump and feed system I believe you should always run a marine engine on the dyno with the same fuel pump, filter and lines you will be using on the engine in the boat as the actual fuel mapping or jetting you will be doing on the engine and what you will want to end up with in the boat can change pretty radically with changes in fuel flow you may see going from the dyno's system to the system ultimately that will be feeding the engine in the boat.
Also remember that fuel pressure alone is not a measure of fuel flow volume, fuel flow is measured in gallons per hour not PSI. Engines burn volumes of fuels not pressures!

Best Regards,
Ray @ Raylar

Another issue is voltage to the pump at any time during it's operation. I used the Weldon 2345 pump and filters that are installed in the boat. I also ran the alternator used in the boat. We never had a issue with the fuel system capacity, and I was able to monitor system voltage on the data logs.
So as well as the pump and plumbing, the voltage source and wiring to the pump is very important.
Hope that helps.
Dick

fuel pressure is very important on efi engines, blown or N/A. should have 42-45 psi under load measured near the injectors.

You can't make a blanket statement like that. It depends on the engine. Some, I may run at 35 psi and others may run as high as 70-75 psi. The pressure depends on the setup.
Eddie

Which pump is it and what kind of power are you making? What is the injection setup? That can make a huge difference.
Eddie

that's kind of reassuring,as my setup runs best at barely 38-40 lbs (496/whipple)...still have to take O2 readings this spring...

Red aeromotive pump runs out of steam pretty quick around the 700 hp level on a efi blower motor. If your running fairly small injectors and turning up the pressure to 70 or 80 to force the injectors to act bigger this happens even earlier as pumps have performance curve-ie-the more pressure you run, the lower the output. also, I always wired my pumps with a 50 amp bosch relay and 10 gauge wire, used the normal efi pump power to just turn on the relay. If your voltage/amperage isn't maintaing because of too small of wire pump output will be lower than rated, you would be surprised how much the voltage can drop at full load with too small of wire. I had to switch from a red aeromotive when I started making over 700 hp, pressure dropped off at wot as motor was using all pump could put out. I went to a essex blue pump, it was better but still was limited at about 750 -800 hp. When I made 950hp the essex fell off on dyno, went to a aeromotive "eliminator" pump, puts out significantly more than the red. I went even higher the next rebuild to 1100 hp, the eliminator couldn't keep up at wot so I added a voltage booster that forces the pump to increase its output by turning voltage up to 16 volts under boost. There are alot of alternatives to those red pumps, Weldon makes really nice pumps, I stayed away from them when I upgraded mine simply because my return regulator and lines were too small to bleed off all the extra fual they pumped when at idle. Nowadays they have controls that toggle the fuel or reduce the voltage at idle if trying to run a huge pump also. Running the appropriate sized injectors also helps, the bigger the injector the less fuel pressure you need to run to make same power-again, a pump that might put out 1000 lbs per hr at 40 psi might drop to 700 lbs per hour at 75 psi, Smitty

Interesting topic.
I was assisting in mapping a blown 502 MPI that was equipped with an Aeromotive Red pump and a Kenne Bell regulator. I was surprised to see the pressure bleed off that fast when ignition was killed, feels like there could be problems with fuel in rails vapourizing. Anyone been there?

i was told that pumps without anti-drain valves do that...mine does