maxcooper

Note that the lift pump does not need to outflow the high pressure pump. It just needs to outflow the injectors, which should be easy to do at low pressure.

Consider what happens under these conditions:
- lift pump flowing 50 gal/hr
- hp pump flowing 60 gal/hr
- injectors flowing 40 gal/hr

Swirl pot:
+ 50 gal/hr from lift pump
- 60 gal/hr from hp pump
+ 20 from return line (60 - 40)
------
+ 10 gal/hr, overflow back to main tank

The hp pump is outflowing the lift pump, and yet the swirl pot is quite full and overflowing 10 gal/hr back to the main tank.

The FPR return line runs to the swirl pot.

The swirl pot should have a significant advantage over the sump if you need to avoid starvation in turns (road race).

If one of the pumps fails, the car will stall. Only the hp pump can provide pressure (since there is an overflow line from the swirl pot back to main tank), and it can only do so if there is fuel in the swirl pot. So, if the hp pump fails, you get no pressure and the car stalls. If the lift pump fails, you get no fuel in the pot and the car stalls (after the fuel that's already in there gets injected into the engine).

-Max

Carl Byck

O'k, simply, the sump you are looking at is for drag, and is not baffled. It will not work for road race. That sump un-baffled is not as good as stock. Walbo would be fine for the reservior, the bosch is a much better pump, both in terms of flow, and reliability. Return to the surge keeps it full, this is a must. The other sump is an invitation for some one to reach under your car, and steal a very expensive pump if you go external, if you go internal9pumps in the sump), the sump is too small. Look at the "1000hp street car" thread on the 20b forum, you will see how to do that set-up properly, it is alot of fabrication to do it right. later, and GL. Basicly you have alot of guys that know what they are doing telling yopu the same thing, Take it, or leave it. Debate OVER...