Update: Got mine wired in and working. Used 12v because thats what its spec'd for. Constant 8.1% ethanol on oregon summer gas. Fuel temp reading is pretty cool too.

 

What are the reasons for using AN lines as opposed to using a Dorman fuel line repair kit setup with factory style connections?

Nothing against AN... Just wondering.

 

Because I have AN line from FPR and rail. And eventually want to go full AN6.

 

Here is my install

 

What kind of fuel temps are you seeing over ambient?

 

Can't drive right now. No license.

Temps were reading ambient while idling.

 

Gotcha. Thanks for link in other thread, will be ordering stuff to add that sensor soon. Taking the miata on a 1200 mile trip in a couple months and won't have E85 all the way there, so will need flex fuel working.

 

Bringing back the discussion about 12v vs 5v supply. I just tested this with the sensor powered by a DC power supply, and fuel pump on 100% DC in test mode.

12v - 7.2% ethanol. Stays that way until about 5.8v. Drops to 6.5% ethanol. Below 5v it consistently drops ethanol percentage with voltage. I wouldn't use a 5v power supply, because it has no room for error. Using a 12v supply gives you lots of voltage fluctuation room without changing the signal.

 

Posting here instead of hijacking Sav's build thread, which currently has the best info I've seen about plumbing and fittings for a flex sensor.

I'm getting ready to install my flex sensor on my 99 and have been planning to do it exactly like Sav shows here. I bought the Dorman tool, connectors, and vinyl hose so that I can do it 100% OEM-style.

https://www.miataturbo.net/build-thr...9/#post1323441

I realized last night that, with this style fittings, I won't have a good way to disconnect a fuel line and empty the tank. I know these fittings are quick and easy to disconnect, but I don't want to subject the plastic Dorman fittings to that many connect/disconnect cycles during race weekends where I'll be using fuel load to set weight. I want to add a spec miata-style fuel sample port for easy tank draining.

I'm new to the EFI-style connectors, so I need some help getting the right combination of connectors without unnecessarily spending a shitload of money. I looked at some of the aluminum/AN stuff, but I think I can do it all with Dorman/Mcmaster stuff. I need to go from the 5/16 EFI hardline on the frame, to an NPT tee for the sample port, to the 3/8 EFI Flex sensor, and then back to the 5/16 EFI fuel rail.

I think this is my current plan, in order from frame rail hardline to fuel rail on engine:

Dorman 800-120 (is this the correct/best fitting to go from EFI quick connect -> rubber hose and hose clamp?)
5/16 EFI-rated rubber hose with Oetiker clamps
Mcmaster 5/16 hose barb to 3/8 male NPT fitting (entering tee)
Mcmaster 5799T23 3/8 NPT tee (5315K48 and 5315K31 for sample port- good reviews on spec miata forum)
Mcmaster 3/8 hose barb to 3/8 male NPT fitting (exiting tee)
3/8 EFI-rated rubber hose with Oetiker clamps
Dorman 800-121 (entering Flex sensor)
Dorman 800-091 (exiting Flex sensor)
Dorman 800-074 5/16 vinyl tubing
Dorman 800-080 or 800-081 on fuel rail

The two bold ones are the only ones I'm really unsure about, but I spelled everything out anyway in case someone else wants to duplicate this setup later. Any reasons why this setup will result in massive fiery death?

Dorman catalog:
http://www.dormanproducts.com/catalo...Disconnect.pdf

 

Seems like a lot of fittings, and a lot of NPT. As you mentioned, you could reduce the count quite a bit by spending a bit on some of the nice two-piece all-metal EFI/AN adapters.

If you do it the NPT way, here is a thread sealant that I found that is meant for E85 fuel systems:

Gasoila® E-Seal Thread Sealant - Pipe Thread Sealants - Products

Gasoila is good stuff. If you've ever had permatex sealant flake and lose sealing properties over time, it doesn't do that.

 

The only way I've found to completely remove NPT from the system is with Aeromotive 17119 (edit: it's still NPT) but it's $140 and only 1/8" outlet, so draining the tank would be way too slow. It also doesn't use the 2-piece threaded EFI clip like the Russell fittings. I could piece together a complete AN setup with Russell and Aeromotive parts, but the number of threaded connections would still be the same... I'd just be swapping NPT for AN. I have no problems with NPT fittings as long as the correct sealant is used. The miatacage.com and the 5xRacing spec miata fuel sample ports both have NPT connections and work fine.

 

Yeah, but you could get down to one 1/8NPT connection (just the port) pretty easily.

Nothing wrong with NPT per se, just a little more of a pain than angled seat seals.

 

This issue has probably already been discussed here in someone's billion page build thread, but...

So I'm switching everything to nickel plated brass, since stainless fittings are either super expensive or cast and ugly. Updated list:

Dorman 800-120 (is this the correct/best fitting to go from EFI quick connect -> rubber hose and hose clamp?)
5/16 EFI-rated rubber hose with Oetiker clamps
Jegs 555-16020 nickel plated brass 5/16 hose barb to 3/8 male NPT fitting (entering tee)
Mcmaster 9151K43 nickel plated brass 3/8 NPT tee (5317K88 and 5315K13 for fuel sample port- good reviews on spec miata forum)
Jegs 555-16021 nickel plated brass 3/8 hose barb to 3/8 male NPT fitting (exiting tee)
3/8 EFI-rated rubber hose with Oetiker clamps
Dorman 800-121 (entering Flex sensor)
Dorman 800-091 (exiting Flex sensor)
Dorman 800-074 5/16 vinyl tubing
Dorman 800-080 or 800-081 on fuel rail

I'm still slightly unsure about the 800-120 and 800-121. Everything I've read says they're what I need, but the push-loc end looks very different from all the plastic connectors for vinyl hose.



vs.

 

I hate NPT. Its leaked on me twice now in the fuel system.

I cranked the ****** down as hard as I could. And then some. Stopped leaking

 

Looks like I was heavily overthinking this. I'm still relatively new to NBs and I didn't realize that it's generally considered safe and acceptable to put rubber hose and hose clamps on the plastic OEM/Dorman fittings. That means I don't need an intermediary adapter tee to jump from the Dorman 5/16 metal connector on the frame to the Dorman 3/8 metal connector on the Flex sensor. The bonus of all this searching is that I found a much nicer racing-oriented fuel quick disconnect with machined-in hose barb, which means I don't have to add a single threaded joint to the fuel circuit.

Dorman 800-081 5/16" Steel to 5/16"(8mm) nylon elbow adapter (on frame tube)
Gates Barricade 5/16 fuel injection hose and Oetiker clamps
Earl's 782405ERL 5/16 hose barb tee
Gates Barricade 5/16 fuel injection hose and Oetiker clamps
Dorman 800-091 3/8" Steel to 5/16"(8mm) nylon elbow adapter (on flex sensor)

Then a Jiffy-tite 22505 routed to a convenient location for the drain port. $19 from Summit vs. $60 for the appropriate stainless NPT QD from Mcmaster.


And then $50 for a 21505 socket and 22505A plug on the drain hose, that way I can plug the ends of the drain hose together and keep dirt out of the line while it's in storage.

Sorry for the thread drift/ newb questions. Hopefully this will be helpful to someone else in the future.

 

I just ordered 13577429 (the small one). Going to see if it works like proven larger ones.

 

It does. I have it on my car. Our gas seems to be around 8% ethanol.

 

I plan on getting a drum of E98 soon to play with mixes and see what works best for me. You tuned for ethanol yet?

 

No. I don't have a built engine. No need to right now.

 

Used the charcoal mount by bending the tabs in. I would NOT recommend the small sensor. It is a pain to mount. I would use the medium or large if I did it again. Used Dorman 3/8 steel to 5/16 barb 90s. They are meant for nylon so I added fuel clamps to the barbs just in case. Hopefully I don't burn to death. I used the stock return line and used a brake line bender to adjust the stock return line. Waiting on my pigtail and wire from amazon to get it running.



*Pigtail arrived. It is not working. Of course my soldering iron and my voltmeter both died. All I have is a test light and crimp fittings. Tried to use the o2 wire. When it did not work ran a temp jumper signal outside of the car to the edu and still nope. Best I can do for now. Going to have to wait for new voltmeter from amazon to figure it out.