Exotic-metal55

Even with custom fuel rail and 8an fuel lines, intank pump and one bosch 044 inline, could not hold pressure to the rail above 4500 rpm. Would drop to 35 psi and lean AFR would ensue.

Went back and tested fuel controller and changed out the pressure regulator. I did figure out, if you un-hook the PSI sensor, you would not get a code and would get max voltage tot he pump. This was only worth 10 psi more but pump would not last long at those levels.

So now, I have a 10an line from the in-tank pump to a small fuel surge tank, two Bosch 044`s are fitted to this tank and each pump will flow into a fuel manifold, then Y into my inline sesnor and the both meet up again and supply the rail. This is a pretty common set up for high power street or track cars but there was no way 2 pumps could meet the high fuel demands of this new built engine. 3 pumps is the new set up.

Our 55`s only have a 5mm to 6mm ID fuel line to the rail, so you do that math with that and most of us are in the danger zone for fuel supply. IMO

Looks funny driving around with a fuel gauge taped to the window but it gets the job done.

e55amgrocket

Seems like part of your problem is however those cars change the voltage to increase pressure. Wonder how everything with the e55's wil do with most of the stock stuff. The more time I spend thinking about this returnless system the more I just want to slap a regulator on and a big MagnaFuel pump with a return line. Problem solved.

Gadget

Where is the fuel pressure sensor??

G

e55amgrocket

His car has a different style fuel system than ours.

Exotic-metal55

Located inline in front of drivers rear tire. Pumps and filter are located there as well.

The E55 also controls fuel pressure as well. 80 psi at idle up to 4500 ish and then drops to 62-65 psi above. Since it drops psi, it seems like it may be voltage controlled as well? Only road tested in Shard`s car and not researched how the pumps work. I like the stock fuel controller, as 80 psi is nice for low rpm and 65 psi flows more volume with the external style controller.

I was close to using a returnless regulator but still know that the one inline 044 wont keep up and stock lines are way to small.

I think using the duel E55 stock intank pumps , have them feed a low profile surge tank under the plastic belly pans and then have duel external pumps pushing to rail would flow well. That would keep the stock system in place pretty much and not require all the custom intank work.

Sneakyneon made a 1000 plus hp set up with duel 8an lines feeding each rail and duel bosch 044 under his pans, as I recall. First major fuel system I ever saw posted for a e55.

Or,, we could just take the fuel tank out and put a fuel cell in the trunk . J/K

HouMike

Now you are talking Brooke. A dad's fuel cell running a few of those bilge pumps to keep it flowing to the duel Bosch up front. Serious what kind of numbers are you making now that you are holding pressure?

e55amgrocket

Hope you aren't serious about that idea.

stevebez

I don't get why the SLR manages with just one pump (am I right?) even though its a return setup?

M-Power_Houston

Nice set up cant wait to see it!

blackbenzz

Because they knew what they were doing. You don't need a 1000hp fuel system when you don't make 1000hp.

Exotic-metal55

Most of our cars make a lot more RWHP and Torque than an SLR, as you know. I was fine up to 560 RWHP with 550 CC injectors but once I added a lot more power, then fuel PSI would not keep up and then would start to lean out. I also had to up injector size , as the 550 CC would not keep up.

I have plans to add a lot more power, so yes I want a much larger fuel capacity to grow on.

Little hard to see but at the top is a custom made fuel manifold to run both pumps into and also have lines to keep the small inline fuel sensor happy. This is all locatd in a very tight location , just in front of drivers rear tire. At the bottom, is the main tank 10an feed line and it feeds the small surge tank for both pumps. Also two bosch relays were installed to run the pumps and work with the stock AMG fuel controller. The black hose with red lines on it , is a 8an Aeromotive (thier top grade) fuel line and that feeds a Y fuel line , that splits and feeds one 6an line to each fuel rail side.



Back driving the car now and will hook up my windshield fuel PSI gauge and make some runs again. It must be minus 1500 DA outside, with the weather we are having !

AgSilver

Yikes!

What are you doing to hold the cylinder heads down or will that not be a problem?

Exotic-metal55

ARP studs are as good as it get`s and custom gaskets.

On the the E55 system , 6mm ID lines will not handle to much power and most of all, the filters are built in the tank pumps. With cars pushing 10 years old and many pumps/filters not changed, then how much flow has been restricted by clogged filters as well. It is easy to hook up a fuel gaudge on the dyno or run up to the window for testing. You see below about 62- psi, then psi is dropping for some reason.

One more thing to add about the SLR: The SLR is a way different animal than our 55. I was in one last week and crawled over and under it. The SLR has 4 pumps!!! Two intank and two external style and to top it off, the fuel is cooled VIA radiator. Not sure the line size but that is double the E55 pumps and one more than I am running now.

AgSilver

. . . and the regulator is on the rail. The fuel cooler is tied in to the A/C system, I believe through the suction line.

TruTaing

This whole build is so cool. Cant wait to see it completed and running!

Exotic-metal55

Yes, did look like regulator was on the rail. The fuel layout showed the fuel was cooled through the radiator.

I am going to add an adjustable regulator with fuel psi gauge up near the rail. The CL55 stock one is located on the tank and is a 5.3 bar.

cij911

Steve - Couldn't we just run and external inline pump, larger line and a return line ? I guess we could even keep the intake pumps too.

2319

A single 044 will do 700 whp by itself. Voltage regulation of a fuel pump has been around since at least 1990 and maybe before, hence the reason the DSM guys hard wire the pump. Want another DSM trick? Put a 10k ohm resistor in the plug for the water temp sensor. It will fool a car into thinking it is cold all the time and it will dump fuel. Will it work on a an advanced computer like that of the e55? I dunno?

cij911

A 044 could be a great option, as well as the larger line and return line for a nice setup.

The DSM / EVO world has progressed a lot since the late 90's...I don't know anyone that recommends the resistor route since openecu days....

AgSilver

Maybe, just for grins, take a look at the E63 bi-turbo fuel setup. I have not as yet done so. EPC might be a good place to start.