E85. When does the fuel pump have to be upgraded?
10-20-2011, 09:43 PM
#17
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From pin 1 of the fuel pump to F25 of the fuse box. The wire comes up into the rear hatch (through a right angle rubber boot) on the right side and goes across the car next to the back of the rear seat to the drivers side, then goes under the drivers side floor sill plate into the fuse box. The ground wire (pin 2) goes to the main ground lug near the spare tire.
10-20-2011, 10:00 PM
#18
Three Wheelin'
I installed a Walbro GSL392 and measure the voltage at the pump with the car running. The voltage at the pump was a little over 12.5 V with the alternator running at 14V at idle. I ran a 12 gauge sister wire along side the original factory wire and tied it into the fuse box on one end and the pump at the other. I also ran a new 12 guage ground wire to the pump. The voltage drop decreased to 0.5 volts and the pump is now seeing 13.5 volts.
The pump running at 3 bar (44 psi) is pulling 8 amps. That is too much current for the factory wire going to the pump, the wire will not melt but you will see a voltage drop that will effect the performance of the pump. Increasing the voltage at the pump also increase the GPH rating so it is a good thing to do.
The pump running at 3 bar (44 psi) is pulling 8 amps. That is too much current for the factory wire going to the pump, the wire will not melt but you will see a voltage drop that will effect the performance of the pump. Increasing the voltage at the pump also increase the GPH rating so it is a good thing to do.
This thread got me wanting to measure the voltage drop at the pump but my car won't be running until next summer if I'm lucky so thanks for that info. Definitely going to be running some jumper wires. Luckily the car only saw 12psi and 2.5bar FPR with the Walbro while it was running, probably why I never felt hot wires. Plus the fact that Florida is just hot in general so warm wires can be attributed to just the climate.
It does get a tad bit hot down there.
10-22-2011, 03:42 PM
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What I have been able to find is that a stock pump can flows 130 l/h @ 3 bar which is 37 gallons/hr. That is 233 lbs/hr which is 388 crank hp (320 RWHP) with GAS.
With E85 you need 20-25% more fuel for the same HP and a 20+ year old fuel pump may not flow like a new one.
With E85 you need 20-25% more fuel for the same HP and a 20+ year old fuel pump may not flow like a new one.
10-22-2011, 03:50 PM
#22
Burning Brakes
Here's a couple pics of my re-wired pump. I intercepted the stock pump wires in the rear hatch area. Split the loom at the rubber grommet where it goes down to the transaxle area. Look for a brown wire and a green wire with a black stripe. Use those wires to activate a common 35 amp stereo relay. To power the pump I ran a 10 gauge wire off the positive terminal on the battery, to an inline fuse holder, then to the relay. After the relay the power wire goes down through a rubber grommet to the fuel pump. There's already a rubber plug, at least on my car, I just cut a hole in it so the wire can pass through.
