I had the fuel pump relay fail on my completely stock 2001 at 180k miles or so. I'm guessing the relay may not be actually up to its 30A rating. Here's how I did it - even if you choose to go a different way, there should be enough info in here to give you a head start and some perspective.

Upgrading the Fuel Pump Relay, for less $$$ - Miata Turbo Forum - Boost cars, acquire cats.

The way I did it freed up one wire that's powered by the main relay. I've been planning to run my oil temp gauge off of that instead of whatever other circuit I used that is interrupted when the starter is engaged.

I'm a big fan of not working under the dash if I can avoid it. Relays take all of 100mA to trigger, where as fuel pumps draw 10A or more. So instead of working under the dash, I remove the hardtop, seat, rear carpet, and rear bulkhead panel. I then run a fused wire from battery to behind the driver seat to terminal 30 of relay. I then cut and extend both ends of the stock fuel pump feed, the fuel pump side goes to 87, the harness side goes to 86, and 85 is a ~3" jumper to ground. The relays I use have metal tabs, and I ground it and mount it with the same m6 bolt. There's a factory ground back there that I attach everything to.

At this point there are 3 relays in line before your fuel pump is powered, but I figure you've just taken 10+amps off the main and OE fuel pump relay, so they'll live forever. If your main relay does still fail, you're not going to need a fuel pump anyways.

Here's the relay and fuse holders I use:

https://www.prowireusa.com/p-513-sealed-relay-kit.html

https://www.prowireusa.com/p-978-sea...black-cap.html

If you want to be bad ass, you could always install a 75amp relay:

https://www.prowireusa.com/75A-RLY-KIT

Curly, I figured I'd put the relay somewhere around there. So it sounds like you basically intercept the stock fuel pump signal with the relay?

For the gauges/accessories I've got a small fuse block. Current plan is to get that secured somewhere in the radio cubby or footwell and get rid of a couple fuse taps and tidy up some wiring.

Thankfully Friday and Saturday are going to be in the 40's so I should be able to work in the garage without my fingers going numb.

What I did was use a 1/8" bspt -> -4AN fitting in the oil pressure port. Then made a braided line to feed the turbo with a -4an 90 that goes to the fitting. I run the oil presure sensor in the sandwich plate. Like you mentioned, I don't like a bunch of stuff hanging off a tee so that's why I did it this way. I bought a steel tee fitting but ultimately opted against using it because it's a bit janky to me. If you think you'll add an oil cooler at some point, may as well just do it all at the same time. Here's a couple pictures you might find helpful. My sandwich plate didn't have a port, but it's aluminum so fairly easy to drill and tap for an 1/8" npt port. I had to hack the IM bracket quite a bit.
https://cimg2.ibsrv.net/gimg/www.mia...1cc514d5a2.jpg
https://cimg1.ibsrv.net/gimg/www.mia...2938259b90.jpg
https://cimg0.ibsrv.net/gimg/www.mia...79283c21ab.jpg


Good discussion regarding removing the fuel pump from the main relay power source. Sorry not to sidetrack this discussion but what are the main power draws off the main relay. The fuel pump and ignition system? Does anyone know roughly how much the OEM ignition system draws amperage wise? I've contemplated doing this but when I switched to the maxxspark ampefi coil setup I'm running, it no longer runs off the main relay which is nice and lightens the load a bit. I know high flow fuel pumps (depending on the model) can draw a lot of amperage though.

Another thought regarding wiring.. someone suggested it over on the BMM discord and it's probably a good idea.. Redoing the engine grounds for the engine to the engine bay (just making nice/fresh cables) and running a new 2 gauge + wire from the battery. I'm not sure how big the OEM + wire is but I want to say maybe 4 gauge? It's definitely not that big and maybe a fresh 2 gauge would help voltage fluctuations? I know my engine ground by the dipstick looks pretty rough and has seen better days. Replacing the engine grounds (I think there's one on the PPF too) seems like cheap/good preventative maintenance thing to do.

When you type it out like that, it sounds ridiculous. But you're right, it's a massive PITA to work under the dash.

As always, thanks for sharing your knowledge. I'm adding that linked supplier to my list of places to get decent electricals.

Another shameless plug for the link I shared above. It's not just a how to, I put what I learned along the way in there. ;) Here's a good post I quoted from Savington.

Thanks I finally just read through that thread. A bunch of the little sensors I'm not running anymore on my car (MAF, EGR, VCTS EVAP), but those probably don't draw too much power..? Nice work on the rewiring of the main relay. Personally I like curly's method if I'm going to "rewire" my fuel pump. I think his way is the way many/most people do it (on other cars). Run a new fused power wire from the battery to a relay. Use the old fuel pump power/load wire as the trigger for the relay. The battery being in the trunk makes this super easy and much shorter wire = less resistance which is nice. I'm running a DW200 on the NB1 returnless system. According to the spec sheet the DW200 draws ~10.5 amps at ~4bar. Does anyone know how many amps the oem fuel pump draws?

Just did a little Googling and didn't find much on the OEM fuel pump draw but the spec sheet for the DW100 says it draws ~4-5 amps between 20-60 PSI. I'd assume the OEM pump might be a little less efficient simply because I've seen the DW pump advertised as having a "low amperage draw" (Goodwin's website). The DW100 is supposed to flow slightly more than the OEM pump from what I remember.
https://cimg4.ibsrv.net/gimg/www.mia...cb8fc9bbe3.png

I've also deleted a lot of those sensors, but I agree that most of those are probably drawing a couple hundred milliamps. Having said that, I'll also be adding sensor likely, so I might bring that current draw back, or even increase it.

@SlowTeg I think that's the route I'll go for the oil lines. Seems like a clean and simple way to go about it. I'll probably get a line with 2 90* fittings as well so I can route the oil feed line along the valve cover and not have it strewn all the way across the engine bay like it currently is.

Might be a bit of a photo dump, but I got a few things done tonight. First thing was running over to the library to grab my latest 3d print.
https://cimg1.ibsrv.net/gimg/www.mia...541e521113.jpg
Fits so well
https://cimg2.ibsrv.net/gimg/www.mia...a7176a68ec.jpg
Barely fits with the actual coil


Man, I was stoked when I got that in the hole. Unfortunately the shaft is just a bit to large to fit, so only one of the 4 fit in. I think 0.5-1mm off the ID should be just right.

Total cost for 4 printed in TPU? $0.65
I might have to start selling these. What I'm actually going to do is revise the drawing, print another batch to make sure they fit and then upload the file to thingiverse.

I also got some fuses installed to this distribution block. A friend gave this to me a while back when we were talking about wiring. I'm hoping to get this installed behind the dash to power the gauges this weekend.
https://cimg1.ibsrv.net/gimg/www.mia...98831b9b80.jpg

Achievement unlocked - Garage TV
Ran it off the laptop tonight, but I'll grab a smart TV box tomorrow so it's always ready to go. I find that having Gears and Gasoline, MCM, BoostedBoiz, CarPassion, etc... on in the background helps keep me motivated in the garage.
https://cimg5.ibsrv.net/gimg/www.mia...27f059d3a2.jpg
Got the TV for free from a friend. Ended up a bit lower than I wanted, but I can always change that later if I really want to. It's mostly background noise anyway

The evap solenoid and check valve came in yesterday, so I plumbed that up. I did ziptie the solenoid down after the photo. This is just temporary to see how it works, but I'm hoping to finally be able to fill up my tank like a normal person in the summer. Link can control this which is why I'm reinstalling it.
https://cimg7.ibsrv.net/gimg/www.mia...88eeebc57b.jpg
Check valve in case the solenoid failed open somehow. Don't want to pressurize the fuel tank.

I got some o-rings in for my new injectors (shout out to @Z_WAAAAAZ ). If anyone knows what the "spool" type o ring is for let me know. My current theory is to go on the top of the injector under the smaller o-ring up there. Hopefully I'll get these installed on Saturday.
https://cimg0.ibsrv.net/gimg/www.mia...8493cbc355.jpg
https://cimg2.ibsrv.net/gimg/www.mia...496dd4143d.jpg
Bottom Cushion on the left. Spooly boi on the right?

Finally, I think I have a coolant leak somewhere. I get a maple syrup smell when I get home from a drive an pop the hood. Still not sure where that is, but it was part of the reason I wanted to finally get the coil pack off the back of the head. The reroute is down there and pretty hard to see/interact with when the stock coil packs are there. Unfortunately there is a good amount of fluid down there, although I think it's oil from my valve cover and/or rear cam seal. I replaced both of those recently to try to combat this but I'm not sure it was successful. I'm debating on either turning the PCV into a breather or possibly routing my exhaust side breather into the intake to try and get some of that turbo succ to lower any pressure in the valve cover. I'm not sure if that would work, but it seems like it wouldn't hurt outside of potentially coating my turbo/intake piping in oil.
https://cimg4.ibsrv.net/gimg/www.mia...0c933eae85.jpg
Grime buildup from being coated in oil

In about a month it will be 1 year on the built engine. I think it'll be 1-2K shy of putting 10K on it this year. Super happy with how it's held up even if it is leaking here and there. I was listening to the engine through the knock sensor today and it's pretty interesting to hear how much louder it seems to be when cold. I assume it's minor piston slap from the forged pistons, but there's definitely more clatter when cold than when it's warmed up, even just putting around. Here's to another year and another 10K... Hopefully :friday:

Nice stuff all around sir. Oil leaks are annoying, but all things considered....meh, send it. Hope you find that coolant leak soon.

The coil seals are neat. I would be interested to print a set once you upload the files. I haven't used TPU before, so a good excuse to buy a spool. For what's worth, a friend of mine has printed TPU o-rings for her diesel truck and those have worked well for her so far.

I hope the Link helps you have a refillable gas tank :D. In for your experience on EVAP tuning.

I forgot to answer one of your earlier posts about IAT corrections for cold starts: I do the same, and remove a bit more fuel on the WUE table (-3% or so). I remove less than it "wants" because the first start of the day for me is still richer than subsequent starts. A couple of things to note is that my IAT sensor isn't in the airflow path and this is all affected by the charge temperature approximation table. Also, the injectors being further from the valves makes a mess of the idle and low throttle areas when cold. I have a strong feeling that adding fuel temperature will reduce the need for this compensation, as fuel temp is part of the Link's modeled calculations. Although the injector flow and deadtimes change at different temperatures, this isn't something we can measure in the ECU, but fuel temp can be there. I had this behavior with the DW 550cc and now the FIC 365cc injectors, so I don't think it's only the FlowForce that experience it.

https://cimg1.ibsrv.net/gimg/www.mia...7ae8eaf2dc.png

Congratulations on the motor! :friday: Hell yeah. I would caution against putting one of those filters on the exhaust side breather (unsure if that's what you meant or not). I can now say I've seen a car catch on fire because of it. At least route it to a catch can and put a filter on the catch can.

I'm not sure what their function is, but they sit on the fuel rail side of the stock injector. There's already a fuel seal there, maybe they're an additional dust boot?

https://cimg4.ibsrv.net/gimg/www.mia...f43f04ac14.jpg

Really cool updates. I see I'm late to the party but my input on a few things you asked about:

• Brass T and oil pressure fittings. I'm currently running the dreaded brass T with the OP sensor hangin' off it and i've intended to fix this, maybe I'll finally do it this year, I thought this might be an easy solution, but I also like the idea of the sandwich plate mount pictured above. Good stuff for thought.
• Fuel pump choices. Curly nailed it, go big since you have an NB. With the NA I purposely went with a walbro 180hp (instead of a 250+) because I didn't wanna overpower the FPR on my return setup. I don't monitor FP, so who knows how this is working (my tuner would love to see this), but AFRs are reliable with id1050 and the car made 310+whp with headroom. Everything else (fuel rail, fuel lines, FPR, etc.) are stock on my car.
• Knock sensor. I don't believe in these (ask my tuner @redursidae ). Kidding, btw, I just run e85 for high boost and track duties and hope it won't det. So far so good. But when I do add the sensor I will be going with the bosch sensor after Curlys input.

I'm trying extremely hard not to make any of the five plus possible sex jokes in relation to your ignition coil seal remarks.

Nice update, man! Did I send those seals with the injectors? I've shipped too many things in the last few months to remember at this point :rofl: Can't wait to see them in action on your car.

Seriously, those coil seals are sick. Love watching you guys make and use things like this on your builds. I need to bribe my buddies that know CAD to make some bits and pieces like those for me haha.

Nope, I got the seals from Amazon from GB Reman. I actually ordered another set of FelPro's that were totally wrong, so I'll have to return those.

For reference, the part number/description is "8-024A Fuel Injector Seal Kit". Rock Auto sells the same ones, but Amazon was cheaper and faster IIRC. ~$20 to reseal all the injectors seems reasonable.

Well, I enabled the evap solenoid and went over to Walmart to grab some stuff. Stopped by their fuel station out of curiosity and sure enough the car happily filled to the brim. Not going to say it's solved yet, but it seems promising. It might have just relieved pressure when I was fiddling with the lines in the engine bay, but I inverted the "active level" when I was idling and it dropped about 2 AFR points, so it's definitely something.

I'm a bit less aggressive with my IAT trims. Pulling about -10 below -10C and tapering down to -1% at 15 C. I need to fiddle with this a bit more, but it seems pretty close to correct for my car. I might need to revisit this at some point once I've got a better idea of how I want to handle it. I'm pulling fuel with IAT but adding fuel with WUE. This seems to keep the car happier when warming up, but also keeps AFR's in line when the engine is up to temp but the injectors are still cold. I'm noticing a little stumble when warming up that I'm attributing to fueling, but still need to dig into the logs.

Thanks for the photo. That was the only way I could see it going on, but Z shipped the injectors with the top o ring and not the spool looking thing, so I'm not sure if he was running them or not. I'll throw them on and see what happens.

what did you print it in? 100% infill? variable infill? etc?
I would want to make that a bit flexible depending on the harness of the TPU.

Glad to hear it has improved already. And yeah, it would be going rich once the solenoid opens. I see anywhere from 5% to 15% rich using EVAP.

The way you're going about it sounds correct for injectors in the stock location, so keep at it. I didn't mean mine was right as with injectors 2.5 inches away from the valves it is certainly an odd-ball, I just wanted to share that I do the same. Out of curiosity, are you using closed-loop at warmup? How much are you richening through the WUE table?

Hell yeah dude, glad to hear the purge valve seems to be helping with the refueling issue. I can't remember, is the rest of your evap system original? Like you still have the charcoal canister, check valves next to the fuel tank, etc? I know we talked about it before but it's buried in this thread haha.

This is fun to hear about and watch as I'm currently taking a 6 week course on EVAP as part of my smog license update training, lol.

Um... I sent it to the library and they did their thing. I have no idea about the printing parameters. I could specify what I wanted, but I'm not knowledgeable enough to know what would work. They're usually pretty good at making something usable. There was a bit of flex, but less than I expected. I did drive around yesterday with the 1 fitted to the coil and it didn't melt or deform, so that's promising.

Right, I forgot you're on ITBs. Either way, I'm sure every car and injectors need slightly different values.
Closed loop activates at 70 C.
WUE is like this right now, but it still needs a bit of revising. I usually consider around 30C and lower to be "cold" and anything above that to be warm, which is why there's a bigger drop at 40C.
https://keep.google.com/u/0/media/v2...o%2Faac&sz=706
https://cimg3.ibsrv.net/gimg/www.mia...fbedc37d31.png


No, it's currently just the hardline->evap solenoid->check valve -> Intake. I am keeping an eye on that setup because it seems like it could suck fuel through the line with the vacuum. I've read that the NB has a cap that will allow air to be drawn into the gas tank to prevent any vacuum from building in the tank, but I'm still a bit wary. I pulled the line yesterday after driving around a bit and it was dry, so it's looking good so far.

FWIW when I got the car the whole system was already deleted and the evap hardline was plumbed directly into the intake manifold with no check valve or solenoid. One of the issues listed was that the car would run really rough for ~30 seconds after getting gas, which I later realized must've been caused by the car running super rich. That's the conclusion I came to at least, correct me if I'm wrong.

One other Evap related question for the audience. The solenoid I got has what appear to be barbs for 5/16" hoses, but there is nothing (that I can see at least) on the manifold that accepts a 5/16" hose. I've got it... adapted... right now with an old vacuum cap, but was wondering what the stock setup used. Was there a step down adapter or did the stock solenoid just have a smaller outlet barb? I found one photo where it looked like they just stretched vacuum line over the barb? If anyone knows off the top let me know, otherwise I'll just do a bit of research and figure out how to best go about it.