water/methanol injection

[Sick280zx]

Hey guys I don't post on here much but for the last month I've been wondering about this. Any one running it on dual weber downdraft 32/36 dgv's. Although I also know alcohol and aluminum causes corrosion . I haven't bought anything yet just asking some veterans before I waste time building a system and installing it.

[1vicissitude]

What are are you trying to achieve with the meth/water injection?

[m1ghtymaxXx]

Meth on a naturally aspirated carbed motor? Not seeing the point. It essentially raises the octane value on the fuel mixture and cools it through evaporation when sprayed further up the intake tract (intercooler pipes, not applicable). It's generally triggered by a pressure switch or MAP sensor, again useless without boost. Perhaps it could be triggered by throttle position or RPM, but I don't see any benefit to your setup except perhaps a marginal power gain through advanced timing, and it keeps your combustion chamber sparkly from the constant steam cleaning. I've never heard of corrosion being a problem, most engines have aluminum throttle bodies, intake manifolds and intake ports in contact with the water/methanol mixture. Unless you failed to mention this is a draw through or blow through setup, you're best spending your dollars elsewhere. 

[Sick280zx]

It would be for the hot memphis summers to allow me to keep timing at the optimal position. Its a f54 block with stock bottom end and flat tops with an n47 head. So about 10:1 comp after the previous owner unshrouded the valves. Also I could then possibly get away with running a little cheaper gas.

[1vicissitude]

Well it is used mostly on fuel injected forced induction motors. The forced induction benefits from the reduction in intake air temps and denser air, which shouldn't be an issue in your carb'd N/A car. I know it is often said "meth/water injection is like running higher octane fuel" but this is a gross over simplification of what is taking effect.

 

Personally i don't think you will notice much difference, and I certainly wouldn't run aggressive timing with all faith in the meth/water to keep it together. Parts and pumps fail, it also just might not work as well as you think. With those carbs and manifold I personally don't like the idea of spraying meth/water, they just don't have the atomization that a good set of injectors will. I would feel uncomfortable with the possibility of there not being a great mixture of fuel/water/meth before the combustion cycle. 

 

The company "Devil'sOwn meth injection" has a message board that would probably be of better help to you. They sell great parts for good pricing and the admins on that board offer tech help. There is also a ton of more technical information regarding meth/water injection on there. Great resource.

 

Edit: side note, even if it did work well enough is the price of a kit ( $500+ ) and the cost of the water/meth refills really worth the hassle? You run through tanks pretty quick.

 

Also, the controllers I have seen are either TPS based or Map/maf. Spraying all the time will be much more expensive than just buying premium fuel.

 

Have you thought about mixing e85 in your tank or setting up a EFI system like a megasquirt? E85 will raise octane easily and cheaply, programmable EFI will allow you full control over your ignition to avoid detonation.

Edited May 2, 2014 by 1vicissitude

[Sick280zx]

Yes I could go back to fuel injection but it will have to wait till I get a stable work schedule. I guess for now I'll look for an e85 pump and mix a bit in the tank. I guess one of these kits will be better off on my turbo diesel golf. Thanks for the insight guys

[dsommer]

Not a bad idea to run on a high compression engine. I was going to run a snow performance system on my car but with 11:1 compression and aluminum heads. I sold the kit. Money can be spent in other areas.

[Tony D]

In the old days, simple water injection was used. Methanol was used to keep the water from freezing...

[Xnke]

You won't get the result you're after...It'll still knock when you run out of turbo-fluid.

 

Just run a bigger cam profile and be done with it. No detonation problems, far cheaper, less hassle, and really, if you're running enough compression to need to retard the timing just because it's hot outside, you've built the wrong engine.

 

I ran 9.7:1 on 87 octane for two years and two straight 100+ degree summers at 36* of timing advance with no detonation at all, on an N42 head shaved down to a 42cc chamber. With a stock cam, yes it'd knock even on 93 octane. With the mild cam that I ran, no detonation at all on 87 octane.

Edited May 3, 2014 by Xnke

[TimZ]

In the old days, simple water injection was used. Methanol was used to keep the water from freezing...

Yep - on this application (carbs jetted for gasoline), the methanol likely won't do you any good (aside from the anti-freeze part), and straight water will likely be more effective.  

 

Just because you usually see this done on turbo cars doesn't mean it would be "useless" for your application - if you are having issues with detonation due to high compression and aren't able to address it in other ways (like switching to aftermarket EFI, or a different cam for example), then this should still work pretty well.  You may have to get differently calibrated activation sensors, but that's about it.  Water injection should allow you to run proper ignition timing to more effectively take advantage of your compression, too.

 

It's somewhat of a band-aid, in that if if fails or you run out of water you are likely to get detonation at an inopportune time.  However it's a MUCH better solution than running an unknown mix of E85 without rejetting your carbs.  I'm a big fan of E85, but this I would be wary of.

Edited May 3, 2014 by TimZ

[Tony D]

If you fill up your tank when you fill up your tank, you will NEVER "run out of fluid"!

 

Basing fears from some idiot too stupid to fill his fluids when he fills his gas tank is a bit over-the-top.

 

I've run Spearco Water Injection, triggered on both vacuum AND boost since 1979. I have NEVER run out of water when driving the car following one very simple rule: when I put gas in the car, I check my oil and water tank and top off as needed. Every 4th tankful, or before each track day, I check brake fluid.

 

The horror stories of running out of anti-detonant is based more on the reality of having a Forrest Gump run your Indy Car Team, and not someone with the common sense to check the basics.

 

Sling Blade would not run out of water. Forrest Gump would...

 

It works, the mechanics of its efficacy is up for debate... But I've known people to screw up their base map colossally because they're tuning with five gallons in the fuel tank and it's reaching 140F changing the density. From that experience one could equally condemn aftermarket FI, C16 Racing Fuel, or aftermarket fuel computers in general by the same rationale of "your fluid could/will run out"

 

So will your gas. Moot point. Invalid argument.

[Xnke]

Seen it happen more than once, Tony. Also seen a Type 1 VW that was run out of coolant and overheated itself to destruction. Think about that one for a minute, then I'm sure you'll realize that filling the tank isn't the only reason that you could run out.

Edited May 4, 2014 by Xnke

[Tony D]

It's the only one I've ever encountered. If Forrest Gump set it up, then yes...maybe he siphoned it all down into the cylinders when the engine shut off... but that usually resulted in a hydrolocked engine on startup.

 

Frankly, if a Type 1 VW runs out of coolant, you're dead. Period. 

 

I think you meant anti-detonant.

 

And again, how the hell did he run out? If the guy didn't size the tank to handle a full fill up of fuel, the Forrest Gump Rule is in play. I ran 25psi on my Type 1 Bus, pumping well over 300 HP to the ground.... they have a 10 gallon tank. a standard Spearco Kit with the 1 gallon tank handled that running standard 88 octane pump gas. Every gallon of gas took about 1/10 gallon of water on average. I didn't like it so close, so I put a two gallon reservoir in, added bigger jets, and rarely if ever used more than 1/2 to 3/4 of a tank per tankful of fuel. The most I used from my memory was a little over a gallon in 35 miles. I also used the tank of gas in that period as well. I was getting 3.5-4mpg making drag passes all weekend at Milan Dragway back in 1983 or early summer of 84. I think that was 25-30 passes a day over three days, and some more 'extracurriculars' off the beaten path as well. I did fill up Sunday but if I hadn't it would have been a dry tank sometime Sunday making passes I'm sure.

 

Bigger engines could use more, my buddy with the 400HP turbo Saab installed a Canadian Wiper Fluid Reservoir in his car...something like 2.5 gallons, used the anti-detonant in lieu of intercooling. He NEVER ran out either, in 6 years of running that car, never ever ran out. He traded the car to a big Samoan dude who painted his house as the exchange. Two weeks after trading the car off and giving specific instructions that EVERY time he added fuel, he should top off with either water or windshield 50/50 methanol mix....guy ran it dry and detonated the engine to death.

 

Forrest Gump... Samoan House Painter...

 

I don't see running out when you know your tank capacity, your consumption rate, and etc... Anything that can happen 'by fluke' is as likely to happen with any other modification as it will with Water Injection.

 

I think more engines are detonated due to lean fuel mixes and intercoolers than anything else. Following that, I can argue that adding an intercooler will lead to detonation due to lean mixtures and break things as well. 

 

Properly executed, Water Injection is like any other performance modification. You will note the biggest detractors  for using water injection are guys who sold intercoolers. Read an old Spearco Catalog from the 70's and they were neutral about it "you don't have to monitor or fill your water injection tank" if you have an intercooler. Frankly, that's about as truthful as it gets... as long as we don't get into copper leaching and non-distilled water contaminants....

 

As someone once said to me: "You can use what you want, just don't get stupid!"

[TimZ]

Frankly, if a Type 1 VW runs out of coolant, you're dead. Period. 

 

I think you meant anti-detonant.

I was wondering about that, too.  

[Xnke]

VW's are oil cooled, gents. Broken oil cooler line...no oil...

 

Same with methanol injection. Just another thing to get hot and brittle and break, when you least expect it to.

 

I see no point in adding complexity to a car just because.

[Tony D]

FORREST GUMP RULE!!!!

Using the example of a broken oil line on a VW is ludicrous. This isn't a 25 or 30psi turbocharged engine. It's a low BMEP N/A application. Your concerns are, IMO, seriously overblown. Oil is a partial exchange medium...I think the "meltdown" of the engine in question has more to do with lack of lubrication, a vitally necessary element in a rotating engine, than it slack of "cooling" at the time. Using your "seeing complexity added" logic, the guy shouldn't have had am external cooler, stuck with the stocker, and limited himself to around 75-90hp the stock cooler can handle.

 

A situation, I might add, which could be expanded to the 120 HP range with water injection, but the audible warning coming from the engine to "lift foot" should your anti-detonant tank somehow run dry should be more than enough to save the engine. On a VW it's more critical than an L-Series.

 

I will also add this is proposed for an N/A car...heat really isn't that big of an issue.

 

You must have dealt with some really rudimentary systems cobbled together from bits and bobs from some PM Article in the 50's to have these breakage and running out of fluid fears.

 

The EXACT same bugaboo can be said for turbochargers and the waste gate! Added complexity that can fail. Better to run on inlet restriction, and exhaust backpressure to prevent overboost and engine damage! That waste gate could fail closed and blow the engine ... (Forrest Gump don't lift that foot!)

 

 

I have yet to have SS tubing become brittle and break in elevated temperatures, nor cryogenic temps...neither of which is n play here. That's what I built my last setup on the Corvair. It's been on there since 1979, I've never run out, and it allows decent spark advance and performance with fuels it was never designed to run on...without a hitch, or needlessly redesigning major engine components at a cost factor of something like 50X what the Spearco Kit Cost in 1982 (replaced the original one phase injection to two phase for vacuum AND boost so I could run my turbo again!

 

Never had a problem. Nobody I know has had a problem using it. Including newer generation Snow Methanol that does stuff my old windshield washer pump system could only dream of doing! Either I'm lucky, and everybody I. Know is lucky...or we...as was advised by the old white dude who sold me the system back then: "don't get stupid with it!"