Water injection tank

[mts]

I use water injection with my SC. It works very well for me. The only issue I have is the size of the storage tank. I currently use the 1 gallon windshield washer fluid tank. This works well for normal driving as I only fill up with water every 4-5 tanks of gasoline. However, when I am towing on flat land I go through about 1 tank of water per 1 tank of gasoline, which is still fine, but when I tow through the mountains, I can only make it about 125 miles before needing to re-fill the water tank. This situation sucks.

I can always go with a different tank, perhaps in the back of the truck, but I really prefer the current windshield washer tank location under the hood. My question is, does anyone know of a vehicle that has a larger than 1 gallon capacity water tank I might be able to adapt to the stock location? If I could get something roughly twice the size of the stock one I would be set.

Thanks in advance,
Mike

 

[mtycruiser]

Dual tanks???

 

[LabRat11]

How about some details and pics of your water injection setup. This is a mod I'm seriously considering.

Also a ? or 2
Do you use tap water, demineralized, deionized?
Do you use only water or do you add a touch of methanol as some online sources mention?

Thanks in advance

 

[mts]

How about some details and pics of your water injection setup. This is a mod I'm seriously considering.

Also a ? or 2
Do you use tap water, demineralized, deionized?
Do you use only water or do you add a touch of methanol as some online sources mention?

Thanks in advance

These are not the best pics, but:
http://miata.cardomain.com/memberpage/213822/14

I use distilled water only in the summer months and distilled water with a 10-15% methanol mix in the winter. The injection is pre-blower.

As far as mtycruiser's suggestion of 2 tanks, I could do that, but would need to fab something to easily switch between tanks on the fly or a dual tank set-up is no easier than just pulling over to re-fill the tank as I always carry several extra gallons of water mix with me in my cargo box in the back of the truck.

Mike

 

[LabRat11]

Thanks for the pix ... that's a clean - neat install.

A few mor ?s if you don't mind

Is that a home fab job or is it a kit?
Also, I've heard many recomendations to have it spray only above 1 or 2 psi of boost. Is yours set up this way?

Also, what kind of performance gains have you seen? Any signs of the 'steam cleaning' of the engine effect?

Bottom line (I guess) if you had it to do over would you do it? Do you ask yourself 'Why did I wait so long to do it?'?


As far as a larger holding tank two options I see ...

http://www.nalgene-outdoor.com/

Look for some of their larger containers. I use the lab grade bottles all the time here in the lab. They come in all sizes and shapes from 1oz to 10gal. If you go this route you will want a bottle made of HDPE

Option 2: field trip to your local pick and pull.

Either way some bracket fabbing is going to be in order.

Many thanks and hope this helps.

 

[Scamper]

You can take a look here for RV water tanks. Come in all sorts of sizes starting around 3 gallons. You get to decide where the fittings go.

http://www.watertanks.com/rectangulartanks/

 

[cruiserdan]

I run 50/50 distilled water/Methanol in mine year-round. My consumption is about the same as Mike's.

 

[John E Davies]

If you mount a second tank at the same height as the existing one, you can simply install a hose fitting in the bottom of both tanks and run a 3/8 fuel hose between the two. Fill the main tank and the second one will fill automatically. The second tank doesn't even need to have a filler opening - just a vent on top. It does need to be reasonably close by (not in the back of the truck) or the main tank might partially empty during a long ascent, which is when you need the water injection most.

If you really wanted to get fancy you could mount a bigger plastic tank in back under the truck and install an inline washer pump. You can get a 3 gallon poly tank from West Marine for $38 plus the cost of fittings. 14"Lx11"Wx6-1/2"H. You would need to fabricate mounting straps and figure out where to put the durn thing.

www.westmarine.com

John

 

[cruiserdan]

One problem with remote tanks is the ammount of "lift" required to pull from them. I believe the "head" on my Flojet pump is something like 9 feet.

 

[alia176]

Go with dual tanks. See George Scolero's writeup on relocating the current tank to another position (for folks with dual batts). I think he used a Toy Celica tank. The brackets can be made up quite easily and requires simple bending and drilling. If both tanks are on the same level then you'll be fine and you won't need to switch tanks.

Another option is to install a tank on the inside of the frame rail where george has his air compressor. It's protected by a skid plate of some sort. Then use a RV demand pump (Flojet) to bring it up to the engine bay.

 

[cruiserdan]

Relocating the tank is not practical with a blower. In addition, in my case, the injection pump is mounted piggy-back on the Cruise servo and part of it occupies the remaing bit of space that the relocated jar would go.

The problem with an additional demand pump is when does it kick in? With water injection the main pressure pump must come in NOW when it is triggered, without lag, and un-interupeted. If not, there is no point having it.

 

[hoser]

Cut a hole and mount this bad boy on your hood. 5 Gallon Capacity.

 

[alia176]

The demand pump's job is to maintain line press at all times, regardless of what the injection pump is doing. If the line is full of press then the injection pump should be happy. Unless of course the injection pump GPM is so much that the demand pump can't keep up with it. If that's the case, can't one simply obtain a larger demand pump? If the folks in fancy RVs are taking shower with these things, how slow can these pumps be? I'm sure the PSI of the inj pump is quite high but what's the GPM?

For Ex: this Flojet pump has a rating of 3.5 GPM @40 PSI (http://www.flojet.com/prodInfoApp/s...ET&catalogId=RV&categoryId=FRMPU&typeId=FRQSP)

 

[John E Davies]

The problem with an additional demand pump is when does it kick in? With water injection the main pressure pump must come in NOW when it is triggered, without lag, and un-interupeted. If not, there is no point having it.

Because it is a demand pump, it kicks on automatically whenever the pressure upstream drops, runs as long as necessary and then kicks off when the preassure builds back up (no more demand). You would probably want to have a switch in the cabin to switch it off when not needed. but when you were driving you would just arm the circuit and forget about it. OTH, it _will_ run dry and keep going until it burns out - a low level float switch or low pressure cutout switch would be a great idea.

John

 

[Rich]

Mike, if you want to spend some money, custom plastic tank manufacturers can make you one any size you want. They will weld it up out of flat stock. They will be able to include fill fittings, vents, and outlet fittings as you desire. If you want to spend a bit more money you can have one welded up out of aluminum.

 

[mts]

Mike, if you want to spend some money, custom plastic tank manufacturers can make you one any size you want. They will weld it up out of flat stock. They will be able to include fill fittings, vents, and outlet fittings as you desire. QUOTE]


This sounds cool....do you have any contact information for a custom tank place? Ideally, the stock location with about a 2 gallon tank would be perfect, but I guess it all depends on how much $$$.

Mike

 

[mts]

Thanks for the pix ... that's a clean - neat install.


Is that a home fab job or is it a kit?
Also, I've heard many recomendations to have it spray only above 1 or 2 psi of boost. Is yours set up this way?

Also, what kind of performance gains have you seen?

Bottom line (I guess) if you had it to do over would you do it? Do you ask yourself 'Why did I wait so long to do it?'?

.

Let's see:

1) It's a kit, an Aquamist 1s. It normally sells for approx $500. I can get you links to some vendors and info on it if you want it.
2) Mine is set-up to spray at about 4.5psi of boost (the setting is variable to whatever you want). That's it's only trigger. Aquamist makes several other kits (more expensive and more difficult to install) that you can map to trigger at different combinations of events. I think one that triggered on boost AND RPM would be ideal and still be pretty basic. IIRC C-Dan's unit from Kennedy's does that. I've also added a basic led to let me know when the pump is running and a basic system cut-off switch for those times when I do run out of water (it's not good to run the pump dry).
3) As far as performance gains, I've not had the truck dyno'd with and without the water injection though there is a local 4-wheel dyno and I've been tempted. I can't say that I believe the water injection provides much of a power benefit, it was done more a a safety thing. However with the water going in pre-blower, it seals the rotors and gets me an extra .75-1psi of boost in addition to cooling the charge which is nice.
4) As far as would I do it again....yes, I would. I probably don't *need* it as I am lucky enough to get 93 octane gas where I live (not that goat piss 91 stuff C-Dan gets and have not had any detonation issues. However, it does make me feel much better knowing its there during a tough pull. Eariler this year I towed my car to/from Virginia International Raceway through the mountains when the outside temps were 97+. It was awfully nice to know the blower charge was being cooled a bit.

Mike

 

[cruiserdan]

Mine is indeed a Kennedy kit(with photoman mods). It does utilize dual triggers, RPM and boost. It comes in when the boost is above 3.5 lbs AND the rpm is over 3,100.
At that point it kicks in with a 90 PSI Flojet pump through a 45 degree 14 GPH stainless steel/brass nozzle that looks to be from an oil-fired boiler application.

The RPM trigger is an MSD unit that is adjustable between 3100 and 3900 rpm. There is a set of chips that you select from to plug into it. They are offered on 200 RPM steps. The pressure switch that comes in the kit is not adjustable but I have seen Hobbs-type switches that are. The nozzles can be had from about 8 GPH to 16 GPH.

 

[John E Davies]

This sounds cool....do you have any contact information for a custom tank place? Ideally, the stock location with about a 2 gallon tank would be perfect, but I guess it all depends on how much $$$.

Mike

Call up any decent big boat shop and they will give you a contact number for a custom tank manufacturer. They do this sort of stuff _all_ the time. Forget the bass boat shops - call a Searay or Bayliner dealer who sell larger cruisers. I once ordered a custom 30 gallon holding tank for my SeaRay - it came with all the holes in the correct locations - most excellent! I can't recall the price - it was about 1990.

http://www.google.com/search?hl=en&q=custom+poly+tanks&btnG=Google+Search

You can also check your yellow pages for "Tanks".

John

 

[Rich]

The tank manufacturer I dealt with was Terracon. They are in Massachusetts.