Water/Alcohol Injection on a L24?

[jknc90]

First off I did search and found a lot of info about using water/alcohol injection on turbos but no info about using it on L24's. My friend was telling me about a water/alcohol injection system that his uncle hooked up (can't remember what car, not a Z though). The system used a nitrous carb spacer to inject the water/alcohol mixture instead of nitrous. He said that you could use the windshield washer fluid tank, motor, and switch and then whenever you press the windshield washer button, the mixture gets released into the carb spacer. Would this work on a L24 with a holley 4 barrel and BSR intake? (If this is a stupid question sorry, but I don't really know anything at all about water/alcohol injection) Thanks guys.

[GrayZee]

There isn't much point in doing that to a naturally aspirated car...

[GeeZ]

There isn't much point in doing that to a naturally aspirated car...

 

Exactly right!

[Daeron]

Allright, I will open my mouth, and if I HAVE to insert my foot than I shall....

 

..but MY uncle still has about 80% of the water injection system installed on HIS 240, with a 280 motor in it. Anti-detonant, is anti-detonant... it helps to allow the driver to avoid detonation. It can allow you to use low test gasoline on a car that would otherwise require 93 octane; it can allow you to unlock more power through less ignition advance, and it can allow you to run a higher compression on pump gas than you otherwise would be able to. (okay, so the first and last items on the list are virtually the same thing, re worded..)

 

My uncle used it for YEARS, but some time ago it got dismantled for some reason and now what is left on his intake manifold just sits there.

 

BUT yes, it can be done, and it DOES have positive effects as I listed above. Is it worth the expense and hassle? Apparently, the consensus thus far is a resounding no.. but my uncle seemed to think it made a difference.

 

The water or alcohol injected serves to help discourage pre-detonation; whether the car is breathing naturally or a forced induction system is used. It is almost certainly not worth using with a stock NA motor, unless for some strange reason high test is not sufficient to remove your pinging. HIS car was running something like 10:1 compression ratio, with an N47 head and an unknown (to me) aftermarket camshaft.

 

In all honesty, I *do* have to say that recent advancements in my own knowledge are leading me to believe that my uncle doesn't know too much about camshaft selection; SO that may have something to do with why he needed the additional anti-detonant... but to GROSSLY over summarize what I have already mentioned FAR too briefly, using a water injection system is not entirely dissimilar to running higher octane fuel.

[Pop N Wood]

I think Daeron is right. Water injection allows you to tune the engine more agressively and still avoid detonation. Obviously on a turbo car that means you can dial in more boost and ignition advance.

 

A NA car doesn't have as many knobs. If the car is built with a low enough compression ratio that it doesn't detonate on pump gas, than the water injection will actually hurt performance.

 

But if you have a high compression motor and need to run it on low octane fuel, your options to prevent detonation are to run water injection or retard the timing. The water injection saves you the performance loss of retarding the timing, but you will still not see the performance level of running the engine on the proper octane gas with no water injection.

 

I should point out the 240 motors are high compression motors. The operator's manual says they need I think 95 octane gas. Mine use to ping under hard acceleration causing me to run premium gas and even octane boosters. Finally I realized my SU throttle shafts were gone causing the engine to run lean off idle. Switching to downdraft webers got rid of the ping and let the engine run fine on regular gas.

[z-ya]

H2O injection works anywhere you want to cool the intake air stream. The difficult part is getting the right amount of water. Too little:detonation. Too much: less power. Also, betting you engines life on windshield washer pump is a little risky.

[jknc90]

thanks for all the information. So I should only use it if the engine has been built up?

Thanks, Jon

[GrayZee]

Water injection can prevent detonation on a NA car, this is true.. but I think what I was trying to say is that there is not much point as there are not many situations were a NA car presents that much of a pinging problem compared to forced induction. It would just be easier to run higher octane fuel, retard the timing, ect.. I have seen aclky injection kits for NA cars, but that is getting extreme. I would guess you would use that on a allmotor race car. Or maybe a tow truck or something hauling a real heavy load! Ha ha...

[Tony D]

Try driving an 0.060 overbored, cammed Corvair in So Cal on 87 octane in the Summer... You quickly realize the advantages of the old Spearco "Dual Stage" Vacuum-Boost activated Water Injection Unit.

 

If your car is pinging on 'normal' advance settings, and you don't want to shell out $4 a gallon for Premium, then distilled water is a CHEAP alternative that will work long term (been on the Vair now since I upgraded to the "Dual Stage" from the P.O.'s installed outdated "Single Stage" Spearco unit in 1990)

 

Running on 87 sure beats running on 91 any day. At 20 cents a gallon more, I can get by with a lot of distilled Sparkletts (or hork it from work for free....)

 

One tank every other fillup in normal driving.

 

On a Z, I'd probably use Methanol or Windshield Washer Fluid that is Alcohol-Based. I don't like the effects of water on the Nissan Head's Alloy.