New Drop In E85 Compatible Fuel Pump, DW300, January 2011

Shouldnt need the isolator for sound insulation. The pump is ver quiet in comparison to other pumps. You will be suprised how quiet the priming is.

I've had my DW pump in for a couple weeks now....(my denso died suddenly....on a sunday drive) i find it to be just as quiet as the denso....no insulator. I do like to hear that "buzz" from the tank though, when i turn the key.

Well,I must have done something right regarding the return. I adjusted the FP to 42psi,line off. But,it drops to 32psi with the line on. Is that normal?

...and you guys are right. This DW pump is dead quiet even without the isolator.

What is your voltage to the pump?

Yes, if you are running 20" of vacuum. The fuel pressure rises/drop with pressure/vacuum. 10 psi of vacuum is roughly 20" of vacuum.

have i not hAd enough coffee this morning or did this thread get jacked? just wondering........thats all.

I am having the same problem. I originally thought it was ok when I first installed it. I had to turn the regulator way back to get the fuel pressure down to 43 psi but thought it was ok. Problem is that it does not drop much when I put the line back on the regulator. After I put the 80 lb injectors and chip in I started trying to drive it. I noticed that the fuel pressure does not jump up like it should when I hit the throttle but it does come up when the boost starts climbing. I think this is causing it to knock on initial hit of the throttle as the A/F ratio starts out high and richens up with boost increase. I will be running new fuel line, cutting off the Saginaw inlet on the stock fuel rail and doing the weld-on -AN fitting, and probably replacing my old Bosch regulator with the Accufab unit as well just to be sure I have all my fuel issues fixed before I start trying to tune it again. It is a very quiet pump though.

The only modifications I did was to send out my Accufab FPR to the guy who posted in this thread who modifies them and welds the fitting on. (he knows how to weld very well,btw)
Then,I bought a new stainless sending unit from nos4gn,cut off 1/4in from the end of the return line pipe(restrictive),then ran new hose from the FPR to the sending unit.
I also opened up the end of the return pipe in the tank. It seems that,when made,the end is flared shut a little. This might not matter,but I opened it anyway.

No drilling in the rail was done.

Gone is the 1/4in return. 42 line off. 32 line on.

Time for a new pump. Think the Supra pump is getting tired.

I installed the Accufab regulator as is with my existing -6 an elbow and drilled out the crimp in the saginaw fitting in the 1/4" return line at the frame rail. Re-adjusted the fuel pressure to 44 line off and it dropped to 38 line on. Fuel pressure now comes up with throttle like it should. I think I am getting close to having the new DW pump under control now. Will have to do some tuning now to see how much power it will support.

If you were to set your base fuel pressure at 48 line-off, it looks like for your particular setup, it will give you 10 psi (or 20") of vacuum drop (and corresponding 10 psi jump with throttle as it goes to 0 vac) with no other changes. This may require a re-tune of idle and low-speed. It might reduce your top-end hp a bit as now your asking the pump to deliver fuel against more: 48 + 25 (73?) psi - would depend on max boost and dc%. Might be an option to consider before re-working mechanicals to get your full vacuum drop.

So the champions are smaller ID than the stocks, but my champion rails take a -8 fitting where my stock rail take a -6. Would the fact that the champions are being fed straight on, on each side, factor into what is better for flow?

I would figure 3 cylinders getting their own rail and feed is better than 6 rails getting 1 feed. But then again, I don't really know much.

I set the fuel pressure to 48 line off and it drops to about 41 line on. Car only makes about 16 in/Hg vacuum at idle due to cam so that seems in line. Only running 15 psi boost right now. Was just about to look at fuel pressure gauge during WOT when the torque converter let go. $$$$$$HIT!

Two Walbro 255LPH pumps are the largest you can possibly fit through the tank opening.
They barely fit and rub while being inserted.
Two 255LPH pumps support some serious HP.

Racetronix - Dual In-tank Pump System G7X - Kit Configuration Page

How well do WB's handle E85?

I run twin walbros in my tank, and have put 3500 street miles on the car, probably 20 dyno pulls, and 40 1/4mile passes this year at the track, as well as flogging it regularly on the street. No issues with the pumps whatsoever.

So has any conclusion been reached if this pump can FULLY support 80 lb/hr injectors with a volt booster? Thinking of making the switch to E85 since my car is already apart.

Hey MNwe4,

One of our distributors, Hondata, used a single DW301 in-tank to fuel his twin-supercharged 2.0L RSX at the Bonneville salt-flats a few months ago. At 18V, it supplied enough fuel for his 700whp off N2O runs and his 800whp on N2O runs.

Hondata Speedweek 2011 results

...and a quote from Doug:

Doug’s twin supercharged 2.0 liter Acura RSX fueled by a single DW301 300LPH fuel pump was up next. Armed with a Boost-A-Pump to increase pump voltage to 18V, “this gave us ample fuel to repeatedly and reliably run our 800 HP twin supercharged K20 engine over the 5 mile land-speed course.”

I'm also wondering the same as you are and considering switching to E85 from Alky this winter. My mods in my sig are pretty similar to yours. I would like one intank pump to support 500-550 hp max, hopefully without a volt booster. I plan on sticking with my 83's and stock fuel lines and rails. Hopefully I can do this just by moding the slock fuel rail input to accept larger fitting and mod the fuel pressure regulator to get the pressure down at idle or line off. Any input would be greatly appreciated. Thanks.