For those of you running walbro fuel pumps MAKE SURE YOU DO THE 12V MOD, and RUN A 12 VOLT RELAY FOR EACH PUMP USED! I installed my dual fuel pumps and tested both of them in the tank before installing the tank. After making sure they both worked I buttoned everything up, and then I tested the pressure of each pump separately. I found out that the pumps were running less stable when run directly off of the stack setup.The pressure would fluctuate as I tried to set fuel pressure over 35 psi. When I wired every thing to the relay, and ran a wire from the relay to the battery to power the pumps the pressure became stable, and I had no problem making 35+ psi. So if you are runnung a walbro fuel pump, and are not doing the 12 volt mod you may eventuallly ruin the pump, or worse lean out at high hp and blow your motor. When I did this with one pump in the car, and when the gauge fluctuated I thought that the gauge was going bad. When dynoing the guy running the dyno told me he thought the pump was not supplying enough fuel and was weak. I felt this was wrong since the pump was a year old and can support at least 500 HP. Now I know that the pump wasnt getting enough voltage to keep up with the powere being made.
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