I don't know if it would overrun the stock FPR because I installed the Walbro 400 and the adjustable Aeromotive A1000 FPR at the same time. I guess we could retune it without the rewire to see if it will support my setup and if not I can do the rewire. We just won't have the kind of data that mrfred is generating.

Dan (drb)

 

I understand your position. You do enough for the EVO community as it is. I would agree that a rewired Walbro 255 will probably support your setup, especially if you do the relief valve mod to the 255.

Dan (drb)

 

I doubt we "claimed" it was due to the oring, just that it is possible it could be the oring as we've seen in other installs and applications that have used orings supplied outside of the kit bleed off at high pressures.

I've watched and done the testing myself, the DW301 flows what we've stated and have had those ratings confirmed by outside sources. There is something going on with the EvoX and Evo 8/9 chassis or assembly or wiring (or a combination) that is not allowing the DW301 to flow its full potential.

We appreciate the work members like mrfred and others in the Evo community have done, especially when it is done in an unbiased way.

I've been watching this thread pretty much since mrfred started it, and I want to further iterate that we have been involved in the EvoM community for a while now, mainly to give the membership easy access to us should there ever be a question about our products.

 

Glad you understand I'm just trying to figure out what works. I agree there is something with the Evo that could be holding it back. I've done a rough calculation on the pressure drop between the pump and the rail using the factory fuel feed line, and when a Walbro or DW is flowing near full capacity it appears to be at least 5 psi, and with the several 90 deg bends, it could be closer to 10 psi.

And the factory wiring is way more limiting than I expected. Perhaps the issue is that the factory wiring can support only so much "power", i.e., with a DW, the higher current demand may cause a greater voltage drop, and thus result in the same overall electric power available as would be available for a Walbro.

 

well BluEVOIX is the customer, he posted in here. someone sent him a new oring to try and it did the same thing.. that's all i was saying. we did a back to back comparison on it around 7 months ago or so.

 

So did I but with a DW. I then did the rewire and hit about 520whp before running out of fuel from the pump on a dynojet. I now have a double pumper and maxed out my 1450s.

 

Was your walboro modified with the release hole punched in?


My walboro 255 was modified (used with FIC 1250 injectors) and here is some details on what I have done.

I replaced and used different seals. In order:

1. Re-used existing factory OEM gourmet from my walboro pump.
2. Double o-rings as provided with DW pump kit.
3. Bought and installed brand new gourmet from Mitsubishi.

All three had the same results. I have not done any fuel pressure testing, for what its worth I did check the factory lines for voltage (multimeter) running to the pump and it was 12.5 volts. And I checked it by using a multimeter on the power wire to the fuel pump and "ground".

Also I checked the fpr pressure hose and replaced it just to rule out a possible variable.

 

Wow, how frustrating was that after tearing the pump out 3 times?! I probably would have given up after the dual o-ring kit from DW didn't work though.

 

so I'm pretty much a noob when it comes to fuel pumps... but have you thought about trying these?

http://www.motoiq.com/magazine_artic...uel-pumps.aspx

 

those are external pumps; expensive, more work to install, and a high flow in-tank pump is still needed to feed it.

 

lol, see, I told you I was a noob...

 

First post updated with 1-to-1 comparison between Walbro 255 and DW301 with my rewire.

 

Awesome information, the most comprehensive fuel pump test that I have ever seen. Thanks for taking the time to do this.

 

Good stuff! Now I see no reason to buy anything but a walbro, but do look forward to your tests on the 400 to see what it might be capable of at higher power levels.

Great work btw, this testing is a huge benefit to everyone. I especially like that your keeping the factory fuel control with the high and low voltage lines because I never want to put an aftermarket FPR on my car.

 

Have you seen the AMS fuel pump test thread? Its awesome.

Beeble and scheides are both getting overrun in their testing of the Walbro 400 on Evo 10s with factory low voltage wiring. Seems reasonable to assume it will be the same situation on the Evo 8/9. They've actually had to drill out the siphon hole to bring the pressure down, so I'm not sure if an aftermarket FPR will fix the situation. Seems a certainty that a Walbro 400 with a high voltage only rewire will require drilling the siphon hole. Maybe I'll get around to installing mine this weekend to see what happens on low voltage.