My EFI Blown 540 is getting closer and I need to figure out the fuel system for the Rayson Craft. I have saddle tanks and I'd like to be able to switch from one to the other while using the high pressure elec. fuel pump.
I've been told elec. fuel pumps do not like to suck, so the idea is to use a mechanical fuel pump to draw from a saddle tank, fill a surge tank that will gravity-feed the elec. hi-pres. pump.
Here's the idea so far, looking for feedback. Thanks!
- One elec. fuel selector for feed lines from saddle tanks
- From tank selector to a mechanical fuel pump (to suck fuel out of selected saddle tank)
- Mechanical pump to a small (1 gal) surge tank.
- return fuel line from surge tank, back into the feed line between tank selector and mechanical fuel pump (this way I don’t need a separate fuel selector to return fuel back to the same saddle tank)
This should create the continuous fuel needed to keep the surge tank full (I hope )
Now for the high pressure side.
- feed line from bottom of surge tank to high pres elec. fuel pump
- from hi pres elec fuel pump up to fuel rails etc, then fuel pres. regulator.
- From fuel pres regulator, back to surge tank (high pres. return line)
I'd end up with 2 sets of feed and return lines (4 lines total) on the surge tank, 2 high pres. and 2 low pres.
The only issue I can think of is I might need to prime the surge tank if I ever let the tanks run dry because it might take too long for the mechanical fuel pump to fill it up while cranking the motor over with the starter. Once it’s full, would a good high-flow mechanical fuel pump flow enough to keep the surge tank full? I've been told the motor will produce somewhere around 1,000 HP.
Hope this makes sense! Thanks in advance for the help guys.