Im running a single DW300 on stock wiring +ID1000's and am out of fuel pump @ 449/364 on E85. Not sure if this is normal, I've heard of people with the same gear making more.

Thinking of adding a 12 gauge wire from the earth line just off the pump about an inch back from the plug, and grounding it to a nearby point. Anyone done this mod alone before? Any opinions on it before I go ahead?

 

usually i've read of people doing something like this kit http://www.streettunedmotorsports.co...rewire_kit.htm

i think there has been a few who have done custom wiring. not too sure if by just upgerading the ground it will help you out.

 

Well I was hoping the upgraded/additional earth line would allow the pump to pull a little more current through the stock power wire. I didn't really want to rewire the whole thing.

 

Basically, if the pump is getting anything less than 14V (and preferably ~14.3V) while under full load, it cannot deliver full capacity. The wiring (both power and earth) need to be able to support a sustained 200W, which in this case would call for 12 awg (3.3 mm2) wiring.

 

Yes I was thinking the current carrying capacity of both the power and the earth would benefit from being increased. I don't know what the pump is actually seeing under full load but given the IDC it needs at moderate boost it's not anything like 14-14.3v.

My question is would upgrading the earth alone provide any gains. I know it won't be as good as redoing it all, but would doing it alone help. Theoretically it should, if I use a larger gauge wire and make it a short run, as a thicker wire can carry more current with less voltage drop.

 

Well I went ahead and upgraded the earth line. Cut the factory wire about an inch from the plug and soldered on a 12 AWG wire grounding it under the rear seat mounting bolt. Prior to the upgrade the injectors went static at 5750rpm, after the upgrade they go static at 6500 rpm. I had to pull fuel out of the map everywhere to get it back to where it was. At 7000 rpm the difference in AFR is ~0.7 which is reasonable and shows the line pressure has improved. Post 7K it's up beyond 1.2 AFR points difference from what I saw the gauge hit. Thankfully E85 is forgiving and I was only running just a bit more timing than on pump.

Anyway I wont run it like this of course but the mod does give some more headroom.



orange = pre mod
red&blue = after mod