I notice that the filter sock is a design I haven't seen before.

I am familiar with the 'traditional'(?) design which extends fully from the pump in one direction, and the advice that I have repeatedly seen that there is only one way that sock should point and feed problems will result if you go the other way.

That fuel bucket thing is new to me too, I presume there are one-way valves to maintain a suitable level of fuel inside.

 

I think a lot of manufacturers switched to them around the time plastic tanks took over, which I think are harder to attach baffles to internally. But yes you’re right, there are several very small holes in the bottom of the bucket to allow fuel in. The fuel return line is directed into the bucket such that it fills via returned fuel faster than it can drain through the small holes in the base.

Back to the DW200 issues; is it possible DW changed the design of the pump at some point in recent years after it was already a known-good-solution? And only the more track oriented users with cars built after X date start to suffer problems?

 

Not to beat a dead horse - I think we have clearly identified the solution to the OP's problem, but food for thought for those of us with DW200 issues:

I took apart my pump assembly again yesterday after some overthinking. I also subscribe to Curly's "no fuel injection clamp has teeth" religion and had re-used the OG Mazda spring clamps when I installed the DW200. I decided to replace them with crimp-style stainless hose clamps that I've been using in places. In doing so, I realized that in my case at least, there is zero room between the end of the output barb of the DW200 and the end of the metal feed tubing. I don't believe this could be by design - after all, this is a universal part, there's no way the length of a generic pump exactly matches the distance between the feed tube and the bottom pump bracket. It also seems like a great way to pass vibration between the two parts. So I cut off a small amount of the metal feed tube, de-burred the cut, and re-attached the pump with the crimp-style hose clamps. It puts a lot less pressure on the rubber mounting puck that I modified earlier. Not sure if that's good or bad.

When crimping on the new hose clamps, it's clear that the pump barb and the tubing require significantly different amounts of clamping. I just about maxed-out the crimp distance of the clamp on the tubing side, while the pump barb has plenty of room left. I still don't know why my fuel filter sock looks so different from everyone else's - I bought this from the fine folks at FlowForce as a Miata-specific kit. Hopefully it's not a big deal. I found the lot number printed on the pump body, in case anyone else is as crazy as I am: 1008-200310. I purchased it in October of 2021. (Edited to add: I heard back from DW, the code is Year 20, Month 03, Day 10).

Two other notes - the plastic wrap around the pump body that has the DW logo was starting to curl up in a couple places, so I cut it off. I doubt it'd dissolve, flake off, or otherwise cause an issue, but why tempt fate?

 

Was there ever any resolution for this? I'm ordering a pump shortly to finish prepping the chassis for my street/track EFR build and was going to go dw200 for the low noise easy swap but now I'm overthinking and leaning walbro 255... Certainly want reliability and consistent fuel supply with everything else I'm doing.

 

Yes the resolution was the dw200 can cause fuel starve and you should buy the warlbro for a track car

 

Appreciate the quick response OP. Sorry looking back at the thread again now I must have glossed over your conclusion and got caught up in the pictures and other members troubleshooting!

 

I looked into "walbro" pumps, since I've noticed for a while that they're all labeled "Ti automotive", turns out this switch happened in ~2015, yet we still call them Walbro pumps. Thought I'd mention that.

 

Interesting point Curly, I believe you'd been a proponent for Walbros over DW for reliability if I remember correctly? Only miata vendor that still seems to sell them is Fab9 which isn't super confidence inspiring.

 

@Peter10 Good-win and 5X Racing carry both Walbro 190LPH and Walbro 255LPH. Plenty of other vendors do as well.

 

I stand corrected my search skills are apparently trash. Thank you!

 

Yeah, I like Walbro(Ti) over DW, but it may be a completely biased opinion based on the fact that my shop only orders Ti. As far as I'm aware, they've never let us down out of the box, only having issues when we do stupid **** or debris runs through them.

 

Pretty sure I was getting some fuel starvation during long left handed sweepers this weekend. Also running a DW200, NB1 turbo. Replying to this thread so I'll come back and re-read it again later.