Water vapor?
 

So, I've been doing some reading and talking, and it's been suggested I hook up a water vapor system on my car... Being that it's construction is simple(and cheap), I'm considering it...

From what I understand, take a tank half full of water(or maybe water/methanol), run an air hose to a submerged aquarium bubbler, apply vacuum at the top... The vacuum will bubble the water and your engine will inhale vapor... I've heard claims from better cooling to better mileage...

Would such a setup do anything for FE at all without tuning(the vapor would allow much more timing in theory which is good for both power and FE)?

Given that this system is basically a vacuum leak (can skew air/fuel mix given that it's measured with MAF), would it be safe to plumb it into the intake manifold? Or air intake tube?

Not enough water vapor to have any effect.
What this mod does is displace oxygen with water vapor.
It could work if you live in a dry climate and can get the humidity of the air way up, like closer to 100%.

I see... I guess the better approach to cooling the intake charge with water is to inject a fine mist of it directly into the TB, but I'll save that project for my Saturn...

Just adding water injection on gasoline engines has almost always been shown to reduce fuel economy.

If anything, you want to warm the intake charge.

Don't say vapor, as pointed out it would be insignificant. Water injection has been around a long time. It was great in 1975 when gas went to crap and there were old hi performance 60s muscle cars running around calling for 15 degrees advanced timing and 12:1 compression on old school heads. Basically the water could reduce detonation. It wasn't for fuel economy it was just to put a bandaid on a problem. Turbos and superchargers can run extra boost with a water/alcohol injection system as well. That is to make lots more power, again no improvement in fuel economy.

But if it makes more power.....than it's more efficient.....so it gets better mileage!!!!

It's just like when you put vortex generators on a wing of an airplane......it gets more lift.....so it flies faster with less power and gets better mileage too....so that's why we put Vortex Generators on cars.

That is what I am going to do. The 8L I am building has 11 to 1 compression and I would like to run regular pump gas.
If I can use RUG instead of premium gas and run a lean tune it will be much more economical.
Not really any application for water/methanol for fuel economy improvement on an EPA and .gov approved production engine.

Thinking more about the setup described and my Navy distilling unit operator days, if you can get enough vacuum on the container and then run exhaust through it (sealed off inside tubes), I wonder if you could get it to boil. You would then get much more vapor as "cool" steam. I have no idea if this would be better or worse then just using water which will flash to steam in the combustion chamber anyway.

Evaporators run about 24 inches of mercury vacuum and that lowers the boiling point of water to about 140'F to 150'F.