A different sort of water tank setup.
 

There’s been some discussion about tanks and level switches lately, so I though I’d share some of the changes I recently made to me WI system.

My original WI install made use of the windshield washer bottle, and I mounted the pump behind the front bumper, just forward of the right front tire. Here's the skinny on the original setup: https://www.miataturbo.net/forum/showthread.php?t=6932

‘Twas a nice and simple setup that kept the lines short and didn’t kill any trunk space- two of my major design goals. Unfortunately, I soon found out that the washer bottle is entirely too small. I measured it out of the car at 1.65 liters, but due to the odd shape and placement of the fitting I’d say that only about 1 liter of this is actually useful capacity. (this is a US-spec NA without ABS) What this translates to is <50 miles of hard driving between refills.

So I basically resolved that I was going to have to deal with a tank in the trunk, though I wanted to keep the pump up front where it was. Short lines = less pressure drop. Of course, a long supply line (tank to pump) would create drop just like a long delivery line (pump to nozzle). Solution? Keep the existing system connected exactly as it is (the washer bottle still feeds the injection pump) and install a second tank, with a transfer pump, to replenish the washer bottle as needed. A bit complex on paper, but as I mulled it over I really started liking this solution.

I finally found the perfect tank from enginerunup.com. Apologies to Chase & WideOpen (you know I love you guys) but this tank was the one: http://www.enginerunup.com/shop.php/...uart/p_21.html Turns out it’s actually a 5 quart Kart fuel tank, but it’s perfect. It’s got a reinforced area at the bottom pre-cast for a 1/8” MPT fitting (just finish-drill and hand-tap it) and the best part- it fits! Namely, I have mounted the tank directly opposite the battery, on a wooden platform (5/8” plywood, cut to fit this rather irregular space) situated above where the jack normally goes. The jack has been relocated to the floor behind passenger seat. It’s perfect- I can still put my big toolbox into the trunk with room to spare.

So you can see the wooden platform covering the jack recess. Mounted to the underside of that is a generic windshield washer pump that I bought from Pep Boys. Trico part # 11-100. Twenty bucks. The tank sits atop this held in place with a pair of ¼-20 bolts into T-nuts on the underside of the wood.

Nylon hose runs across the front of the trunk, forward through the passenger’s tunnel, then down and forward through the factory plastic rail on the inboard side of the rocker.

This project finally forced me to remove the last vestige of the A/C system- the evaporator box. Surprisingly heavy sucker, and with that out access to the firewall has gone from an utter nightmare to a fairly pleasant experience. I mounted a bulkhead fitting in the smaller of the two A/C tube holes to pass the hose up to the front.

Now, the electronics:

Mounted in the washer bottle are two float switches: http://www.alcohol-injection.com/flu...itch-p-10.html
The description on the website is wrong- turns out these are actually ½”NPT (not 1/8”) but such is life… You can set these up to be either normally open or normally closed depending on how you rotate them. “Normal” in this case is when the water level is below the level of the switch. I mounted the two switches at different levels. One on the side of the tank defines the upper level, one on the back of the tank defines the lower level. Both are installed in the “N.C.” orientation and wired to a DPDT relay as indicated.

When the water level in the washer bottle drops below the level of the lower switch, the switch closes causing the relay to energize. This activates the pump and also places the upper switch (which is also closed) in-circuit. Thus, even after the water level rises above the lower switch, causing it to open, the upper switch continues to hold the relay on until the water rises to the upper limit. Then the upper switch opens, releasing the relay and taking itself back out of the circuit.

The result? Well, after finishing this up I went out on a run through the mountains with the local Miata club, and was pleasantly surprised that after 150 miles of nearly continuous on-boost running, the big tank was only about ½ empty. Under normal driving I fill it up about once a week whether it needs it or not, and it usually doesn’t.

If nothing else, maybe others will be interested in this tank for use in a “conventional” system. It’s really slick- fits in there like it was made for the Miata.

In fact, with the remote filler that Kung Fu Jesus discovered, the tank could be almost completely hidden- the only reason it’s currently protruding into the trunk at all is to make the filling hole accessible.

Details on the washer bottle itself...

joe that's brilliant. what pump do you use between the bottles?

The schematic shows a windshield washer pump.

Now that is a cool setup. That tank you have is exactly the one I was looking at when I was getting ready to buy one. Might still get that tank because I too like my trunk space.

Just a generic "Universal" windshield washer pump. Specifically, a Trico model 11-100. Link: http://www.tricoproducts.com/catalogs/washerpumps.pdf
Nothing special at all about this pump other than that it happened to be sitting on the shelf at Pep Boys at the exact moment that I was searching for a pump, and since it's a universal type it has hose barbs for inlet & outlet. Many of the OEM-replacement style have odd inlet fittings designed to mate directly to a tank.

This was the second pump that I tried, actually. The first was purchased from JC Whitney, and failed after about 10 seconds of operation. This is the one NOT to buy: http://www.jcwhitney.com/autoparts/P...003809/c-10101

I'll also add that I did have to use some flexible hose between the tank and the pump, and then from the pump to a hose-barb adaptor on the regular nylon tube that goes up to the front. Since I'm running methanol I decided to splurge on some fancy silicone vacuum hose, rather than using the rubber stuff that I normally keep on hand.

Thanks. I was really happy with how well it came together, especially since it was a race against the clock. The project took a few days, and was finally completed and working the night before a huge fun run.

I do know that you NB guys have a slightly different trunk layout than us barndoor folks, but I've not spent a lot of time in an NB trunk so I'm not sure what this space looks like in your car.

I'll measure my available space and see if it will work.

Pretty sure us NB guys have the same kind of space over there. There's a little plastic cubby under there that might be useful for *something*.

I wonder though. If I use the aquamist high speed valve and their race pump, will the length equate to pressure drop if it's a pressure demand driven pump? 12 feet of 2.7mm ID line is more of a surge suppressor I'd think. But the tank itself... nice.

I guess I'm lucky for once being Canadian....our washer bottles have over 1 gallon capacity.

Very clever, I love the tank, but can the washer pump move water fast enough to keep up with your water use on the track?

Seems to me that a slightly less ambitious person like myself could mount the water injection pump under the plywood that holds up the tank (well I have some sheet aluminum, so I would use that) in the well where the jack used to be.

Joe,

I think it's great that you keep working and finding different solutions to various problems.

But if you were worried about pressure drop why not just fit the pump in the trunk and one of these:
http://www.turbobits.co.uk/acatalog/...y_806_201.html

If you fit it directly before your water switching device/valve and up the pressure of the the pump to just slightly over the switching pressure you've got no pressure drop between your tank in the boot and your water valve under the bonnet, plus it also means you then have 2 pressure fail safes.


Cheers
Mark

Though I haven't tested it, it's my impression that the washer pump is more than fast enough to keep up with any rate of consumption you could throw at it. On the average, it seems to take maybe 20 seconds once triggered to fill the tank to the upper limit and shut off. I'm guessing that the volume between the two switches is maybe 750ml. So let's call it 37.5 ml/sec. That comes to roughly 35.7 GPH, and my nozzle is rated at 3 GPH. So assuming I am running at maximum boost continously, I have a margin of well over 10:1. Assuming the exhaust manifold doesn't melt first. ;)

I think I'm going to add an LED somewhere in the cabin that indicates when the lower switch is closed. That little washer pump is bound to fail eventually and while I have a failsafe on the boost controller, I'd really prefer to know about a transfer failure before the washer bottle runs completely dry.

Should be a simple addition, I just have to find space to mount yet another indicator.

Joe, your posts are as ever well written and contain some ingenious ideas. Thanks for another great writeup



(which i will hopefully get to use one day on my own car)

Love that idea and you take the word innovating to the max. Good job.

An Update:

I finally got around to doing the warning light install. It’s pretty slick.

I wanted to put the light into the stock gauge cluster, and I recalled from the list time I had it out that there were some unused “idiot light” positions. So I removed the gauge cluster from the car and held it up to a light, which revealed that the position just to the right of the Seat Belt warning (viewed from the normal position) is a washer fluid warning! What luck. So I removed the bulb from the seat belt position and moved it over to the next hole.

What really surprised me however is that while this bulb position is supplied with +12 just like the rest of them, the other side goes to a trace that just terminates at a dead-end copper pad- it does not go all the way to the connector. According to the Yorba Linda / Madracki wiring diagrams it’s supposed to show up on position 1L at the gauge cluster connectors, but it’s not in the FSM diagrams for either the US or Canada. Also, you can see in the picture that pin 1L is in fact labeled “Washer” but it’s like there’s a missing jumper that wasn’t installed at the factory to complete the circuit, nor was there a wire for it in the mating harness. Do you UK folks have a washer fluid level sensor?

Oh well. I carefully soldered a wire to the pad where the trace ended (it’s *VERY* easy to melt that plastic) and then as you can see I used a ring terminal and tie-wrap to secure the wire. Otherwise I’m fairly certain it would have torn the plastic. The wire goes into the existing transfer circuit as you see in the updated schematic. The diode is there to prevent the transfer circuit from back-feeding the rest of the car through the Meter fuse, since my transfer system is powered in the ACCY position. Also, the +12 feed to the lamp is indicated in gray since it is already provided for you in the cars wiring.

So with this circuit, the lamp comes on when the lower switch closes, and stays on so long as the pump is running. If I wanted it to operate only when the lower switch was closed a second diode placed just above the point where this line connects to the rest of the circuit with the stripe (anode) facing downwards would prevent the lamp from going to ground through the upper switch when the relay is active. Unfortunately, that part of my circuit is encased in hardened epoxy right now, and therefore inaccessible. ;)

Just keeps getting better and better.

Joe....

That's cool. My car with ABS has a functional "washer" warning light, since the bottle is up between the nose and the drivers front wheel. You don't know if it's out of fluid otherwise. It's a '95... BTW....

Maybe that trace is only active on ABS cars? I haven't had the cluster out in my car in a while.... (hum.... maybe I should pull it to check on those LEDs. <G>

Dave,

Good point, Dave. I hadn't thought about that funky ABS water bottle. I'll have to re-check the FSM diagram, maybe it's hidden somewhere with an ABS note.

I'll never understand why there are so many tiny little inconsistancies in the Miatas wiring harness, like the one wire for the VSS only being in the instrument harness if you have cruise or an A/T, despite the fact that the cruise computer harness is there on all cars. I'd think it'd be a lot easier to just have one single harness with all wires in it to accomodate every possible LHD car built, rather than have to juggle three or four different versions of the harness depending on option pakage.

Looks like maybe people with ABS can just tap the blue wire at position 1L of the instrument harness rather than having to solder on that flimsy plastic circuit board.

This is a fucking sweet setup...love it.

Sweet warning light. I am going to copy the tank part. I found the same one for a lot less from a carting place.

http://www.out2win.com/catalog/fueltanks.html

I tried to get the 6 quart tank first, but they tell me G-Man stopped making them.

I have the jack shoved into the cavity in front of the spare, and the pump will be moved to just underneath the tank.

Nice find. I hadn't even thought about Kart tanks before I ordered mine, but it makes sense- a lot of karts run meth, and by definition they need small, cheap, vented fuel tanks. I'm guessing that this must be sort of a standard tank for some Kart class, since there appear to be tanks from several different manufacturers that conform to that basic shape & size.

I hope this isn't too far off topic but do you remember what the idiot light on the far left is?

Joe,
If you ever want to sell your car let me know!!!!! Yet another slick addition.

For those looking for that tank. Here is another option.

Ebay:
http://cgi.ebay.com/ebaymotors/ws/eB...m=110014281291

27.99$

Just have to pickup mine across the border and install it. Almost done with my Aquamist HFS-5 system. Thanks for the idea!

That will be a perfect fit. I use the same mounting for the tank and even used that hole under the wooden platform to mount the shurflow pump.

Nice write up and nice installation. I have had my Devils Own Water Injection system installed for more than a month and love it. I have a different setup on my Miata though since I have a JRSC. I also am running 80% methanol. My pump is mounted near the washer bottle on the fenderwell. And my 4 qt tank is mounted where my spare tire was. My car is always within 30 minutes from my home, so I removed my spare and jack to save weight.

Let us know how your DO system works on your motor. I know that you will be as happy as I am.

So basically you can almost double the water you carry on board. And by running 2 pumps, the 2nd isn't really an accumulator (typically pressurized inline) but really a surge tank.

I really like this, this would be a nice simple way for me to avoid running outta juice on track.

How's it holding up btw?

Double? More like quadruple. The stock tank has a capacity of about 1.5 liters. And yeah, it's not like an accumulator system. The stock washer bottle is still the "primary" tank, the second tank serves as an automatic refill system for it.

So far so good. Since replacing the JC Whitney pump with the Trico I've had zero problems with the system, running about 50% methanol. Usually when the washer tank starts to get low the switch will come on as I'm going around a turn, then it runs for about 20 or 30 seconds, and shuts off. I usually don't even notice it- the washer bottle just magically stays full all the time.

out of curiosity, anyone ever thought about using the truly wasted space in the passthrough areas between the cabin and trunk? It would keep the water closer to the CG of the car. The lines could also be shorter. Just a thought.

I removed the spare and jack due to weight reduction advantages for the track days. So I have lots of room in my trunk. Here is what mine looks like. I put it here to help balance out the car.

Attachment 214971

That tank is kinda small man

It looks ~4quart/1gallon so it should be sufficient for 30 minute track sessions, yes?

FWIW...I have a 1990 with a solid/flat trunk floor (no dips). In the NB's they have a lowered portion on either side (battery drops into right side)...so I did the same thing and have my sitting below the trunk floor...makes it easy to carry extra items and still have use of my bottle.

Yours is a fantastic idea!!

I can use 1.5 gallons in 15 or so minutes of full boost. ;) It looks more like 2 quarts to me, but the OP is the only one who knows for sure.

I'm pretty sure it's this one: http://www.alcohol-injection.com/4-quart-tank-32.html

Yep, it is a 4 quart tank. It will depend on how long your pump runs and the size of the nozzle. I run an M2 nozzle and 30 minutes is no problem on a road course. I make 10 quarter mile passes on just over two quarts.

Joe, nice install... but what about installing a larger primary tank (like the Canadian models) or a secondary tank in the engine compartment for comparable quantity to simplify things?

it is alot simpler to have stuff in the trunk trust me.

I considered a Canadian tank, however they aren't all that much bigger, and very hard to find here in So.Cal. The tank in the trunk was cost effective, gave me a hugely increased capacity (roughly 6 quarts useful, compared to about 2 qt for the Canadian tank) and was actually pretty simple to do.

As to a larger tank elsewhere under the hood, that was my original idea. There just ain't space for it however. I couldn't even find a place to mount the pump in there, which is how it ended up inside the nose just ahead of the right front wheel.

wow what a idea man one of the best builds i have seen super nice congrats nice writeup too

Damn, that's a really nice setup you have going there.

REcently, with my head burried in something while doing wiring, I was looking at the front fenders, they are pretty hollow. Since your tank fills itself, you could use it there. But basically, I don't see anything wrong with your tank. It's a nice set up. Except what's the point of a DO over letting the MS do it?

But then, where would I put my speakers? And where would I stuff my bagels when coming home from costco? (Jewish? Why do you ask?)

Fabricate a water tank to go inside the fender? Let me know how that works out. :D

Well, I did this install nearly a year ago, for one. Didn't have an MS then.

Ultimately, I'd like to experiment with substituting the MS in place of the DO controller, keeping the DO pump, etc. Problem is that I still haven't seen a valve anywhere that is reasonably priced and will work at the PWM frequencies that the MS outputs for the WI, which is basically RPM/2.

I've had the pax seat out for some time now, and it's really very convenient. Three cases of beer will fit neatly on the floor beside you, forming a platform for other essential foodstuffs to be placed atop, such as three additional cases of beer. Driving up to a place where a group of friends have congregated (such as the garage next to mine) with a Miata laden in this configuration is good for a laugh. And then they start drinking your beer. :bigtu:

I plan to implement a bigger tank where my 1 gallon sits and put in an accumulator soon i let you all know how it goes. I am thinking with 4-5 gallons i will be abit happier :D

Joe, that tank setup is ingenius indeed.

However, wouldn't it be simpler to gravity feed the rear tank from the one under the hood, and install the low level warning switch as well as the pump in the rear?
Less room for potential problems that way..

***

I am in the process of preparing my car for a water injection setup, and I have a come up with a solution for the limited tank room in my NB.
Trunk space is limited already, and I cannot afford losing any room there. Space behind the passenger seat is occupied by a large amp, as well...

This is what I have come up with:

There is a plastic lined "cubby hole" in the driver's side of the trunk. There's actually quite bit of room in there when you remove the plastic lining.
This location would be the main tank area. The top of that tank would be level with the trunk floor and maybe carpeted even.
There are also two rather large, almost pyramid shaped hollow spaces just to the front of the rear wheels.
In addition, There are some assorted hollow spaces on the underside of the trunk, specifically on the driver's side, away from the muffler. (I have a Borla, which takes up far less room than the stock muffler)

I am going to build about 5 (maybe more) custom water tanks out of copper sheeting, about 0.5 mm thick (0,02", or 24 gauge). I used that stuff before to make a large heatsink for the wideband O2, and it is easy to work with.
I will just build cardboard tank prototypes for the spaces I mentioned above, transfer the final shapes to copper sheeting, bend where necessary, and solder the rest.
I could use aluminum and have it welded, but I am cheap.
Next step would be joining the tanks via copper tubing, installing a level sensor on the bottom of the lowest tank and attach the pump there, as well.
A filler tube will be extended and plumbed (with a cap) next to the gas cap under the gas cap lid, and all of the tanks will have simple, check valve style air vents to prevent airlocking during fill ups.
The highest point will be the filler neck, and the lowest will be the tank with the pump attached.
A very rough estimate yields about a 5 gallon capacity for the combined tanks.

I attempted soldering the copper sheets together as soon as I had this idea, and it works. I have two pieces of copper sheets soldered at a right angle sitting next to the computer as I type this. I used a heat gun and a soldering gun, that's what I had lying around the house. I'll get a small torch for the actual work.

The idea of using the existing warning light in the dash is brilliant. I certainly would like to incorporate that into what I do, as well.

So far, that's my plan of action. Carrying more than 5 gallons of water onboard without losing any usable space in the car.

I drive on boost much of the time, (no speed limits on the freeways here) and I just do not want to run out of water on the freeway - it's a bitch to pull over and find water.

Any thoughts?

OMFG...you're a god.

+1 Hustler said it, you are truly amazing.

Thanks guys..

Actually, I just got off the phone with a friend who happens to be an accomplished mechanical engineer.
He suggested I could actually use PVC, using a "hot air welding" technique. Apparently, you can run perfect, airtight plastic beads with this tool, and create any shape you like out of pvc. It is available in a variety of thicknesses and grades.

Here's another idea for making the reservoirs:

Place a durable trashbag inside, and then cover the bottom of those cavities mentioned in my earlier post with stiff cardboard/plywood, etc. Blow air in the trashbag (with care to prevent it from blowing) so it will unfold and settle in the cavity. Shoot expanding foam in the trash bag, let it cure. Then, remove the cured foam/trashbag, remove all plastic, and you have a "negative" of the cavity...
Trim the odd shapes to obtain a sensible shape with workable sides, use cardboard to make a prototype tank, and proceed with aluminum, copper or plastic as you wish.
Vent caps, nipples, interconnecting lines etc will of course be installed in the manner described in my earlier post. It also would not hurt to pad the reservoirs with foam or neprene.

I will do this one way or another and post all the developments with pics here.
I see no reason why it should not work flawlessly, because I happen to be stubborn as hell.
Please refer to the Bi-Xenon headlight conversion I made on my coffee table at home.
https://www.miataturbo.net/forum/t38930/#post451476
(Third picture down)

I have also come up with an interesting design to make a hand held hot air plastic welder.. I'll toy with the idea ro see what I can do.

BTW, I am thinking about getting the AEM progressive injection kit. (30-3000)
Still trying to find a good deal on one of those.
Any ideas, suggestions are welcome and appreciated.

http://abefm.smugmug.com/photos/513016100_7KjQo-M.jpg


http://abefm.smugmug.com/photos/513010266_hE4GC-M.jpg

http://abefm.smugmug.com/photos/513014093_R8uEz-M.jpg

Yes, there's plenty of room in there. And I took the original carpeting to make a mold to give me a rough shape, then trimmed it till it JUST fit.

The power antena was the next limiting thing.

Pumps are for pussies, pressurize the tank with boost pressure. :-P And take pics.

Why?

I want to run a progressive system where the amount of water changes with the conditions.
Air, fuel, temps, etc are wildy different in NA, transition, low boost and high boost conditions. Injection needs to start, say, at 2psi and max out at 12.
If I were to use boost pressure, 2-4 psi would produce all but a drip slightly worse than that of a horndog GI with a punchcard to a Hanoi brothel.
A decent injection system needs many times over the pressure generated by boost in normal driving conditions.
And it needs to be progressive. Can you imagine what would happen if your fuel system was not?

Oh yes, I will post pics, too.

BTW, I like your sub solution, but I would be worried about damagaging it with whatever I put in the trunk.

I installed the largest possible speakers (8") with the deepest bass I have heard in car components in the back deck. They are pioneers actually, but they don't make them anymore. At 360 watts a piece, they are formidable. They leave no room - literally and figuratively - for subs.
I also replaced the door speakers with 250 Watt 6X9 Pioneers. Took some work and modifying, but I made adapters, and they rock. Tweeters in the doors are operational, too.
I then installed a 600 Watt amp to drive all that.
I listen to Pink Floyd, Tool and some commie bastard Turkish rock group called "Duman".

Holy crap..enough threaddrifting...

anything on this yet?

Huh, I wanted to put in 6x9's but ended up with some infinity refrences for the doors, and I have these dinky 35W(rms) pioneers in the deck lid. I'd love to see pics of your set up, post them somewhere?

My amp is pretty solid. Overheating is an issue (it's a 1200 watt amp!), but it'd very solid, and up off the floor so nothing really hits is. The grill over the box is pretty solid as well, I've had some big stuff in the trunk and not had problems.

Make a thread about your stereo and link it here. :-)

So, the point is: Have you considered fiberglass? Wear clothes you're ok throwing out when you make it, and aside from taking some time to make, it comes out nice. Seems easier/lighter than copper, and no corrosion.

The idea is you put a nozzle (even two, one which works at lower pressure) and "inject" ahead of the turbo. Lots of people did this in the draw-through-carb set up days. My motorcycle had this for a while. And, spray would be proportional to boost pressure, reference the manifold.


If you're spending $8/gallon on gas to make 200 whp, you're doing something wrong. I'm guilty of this myself, but, try to worry less about doing it perfect and more about doing it well enough. The most famous quote of the guy whom they named the physics building after at my school, nobel prize and all, "Every experiment should be done as poorly as possible". Perhaps some dyno time? 5 tanks of gas saving's will pay for a half day dyno session, and you're sure to pick up 10-30 hp and be able to run on $3 gas (unless you live out of the US)

Joe,
Do you HAVE to PWM the valve? Can you find an analog valve?

Very nice dual tank set up with indicator light.Impressive
-G-

Believe me, I am not doing anything wrong.. It's just that 8.25/gal happens to be the price everyone pays for good ol' gas here in Istanbul, Turkey. Hell, it used to be damn near 11 bucks for a while..
All Turkish drivers are truly pissed off by the fact that what they are burning in their engines is the most expensive fossil fuel in the planet.
Most, no almost all cabs are running LPG conversions. The conversion sector is huge here.

OTOH, I know full well I have about 50 more ponies to let out of the barn, so to speak. It's just that I am being as conservative I can with the preciously expensive and yet crappy fuel we have available here. No need to burn/break stuff.
That's why I need water injection. That way I can keep logging and tweaking with some decent headroom.
Besides, I still bury the speedo needle on the freeway with the way the car is now..

godless commie the wi most certianly does not have to be progressive it justhas to be sized correctly my setup is a prime example of this with 1 nozzle you can flow enough WI to totally max out that litle mp62 you have there without being progresive. You people from Constantinoble are weird btw. If you know your system you will know the usage aprox per minute of boost and then you should plan aroun this. I for example carry up to 5 gallons extra water if i want to go somewhere far away most of the time.

If I need to carry a five gallon tank in my trunk, it just defeats the purpose of having a trunk in the first place. I cannot put anything else in there.

Guess I am weird that way.
One trip to Metro (kinda like Costco) fills up the trunk to the brim.
We do take mini vacations, and put our stuff in the trunk.

i put the extra in the seat next to me man.

Another way of saying you're single I guess.. :)

My wife uses that seat.
Seriously, we have succesfully carried a large table for eight, an 8 1/2 foot tall tree for the house, assorted pieces of furniture, 8 racks of wine glasses and more bulky and weird stuff at one point or other in or on this car...