Wankel7

I was wondering if anybody has seen or heard of a TII run using no intercooler. Just using water injection as the means of cooling the intake charge.

Any pictures?

James

1987RX7guy

iTrader: (3)

I haven't see it. I don't think I would want to be the one that finds out it doesn't do the job adequatly.

BTW I saw my TII now. Its purty.

White_FC

Could be done, running stock boost... After you raise the boost it'd be anyones guess, yet probably quite do-able.

You would be far better off keeping the intercooler there AND running water injection after it.

Why would you ever want to do this??

1987RX7guy

iTrader: (3)

don't you know its the latest ricer mod. "Intercooler what intercooler we have Taip arr wata coolinG boi!"

lol

I don't know why he asked but I don't think he is seriously contemplating it on his car.

Wankel7

I understand that no doubt. I dont know. I figured it would be intersting to try. See what the throttle response is like with out it.

Of course watching the intake temps and AFR.

I guess it would be hard to tune the water to match the cooling needs of the intake.

James

White_FC

Well yes similar things have been done to drag cars before that i've seen..
They are however almost always running straight methanol..

Possible? yes! Silly? Yes!

rotarygod

iTrader: (1)

The biggest problem that I can see is that you can't run out of intercooler under boost like you can water. Water also takes up useful space in the combustion chamber that could otherwise hold more air or fuel. No thanks, not for me.

Wankel7

I agree with you on the saftey of an intercooler. However, you are wrong about water injection. That is not what happens. I really do not want to do a write up to explain it.

If this was done I would just do it for grins.

James

rotarygod

iTrader: (1)

Here I'll directly quote Corky Bell since he knows more about forced induction than anybody on this entire forum regardless of what people think. Don't take that personally Seriously don't!

"Water Injector

The water injector, which forces atomized water into the intake charge, is not a very interesting device. It has little place in a properly conceived supercharger system. To stake the safety of a supercharged engine on an inherently unreliable device is an idea whose time has long since passed. Like the intercooler, the water injector's purpose is to reduce intake charge temperature to avoid detonation, but it doesn't work as well as an intercooler. The water vapor itself takes up space in the intake charge, leaving significantly less air and fuel to burn and requiring that boost stay raised to stay even in power output. The water injector also suffers from the "ballpoint pen syndrome," since it runs out of fluid only during use."

"What is water injection, and when is it needed?

Water injection is the spraying of a fine stream of H2O into the intake system. Heat absorbed upon vaporization of the water has a strong cooling effect on the hot compressed air exiting the supercharger. The reduction in intake air temerature reduces the tendency to knock. Don't be too hasy to create a margin of safety on detonation based on an unreliable device. Water injection is best used when boost levels over 6 psi are desired but no intercooling is present. Do not allow a situation to exist where the water injector is used as an excuse for improper air/fuel ratios. All things considered, you would be far ahead never to have heard of a water injector."

That is all he mentions of it in the entire book even though an entire chapter is devoted to intercooling. Yes it does deal with using it when no intercooler is present but why would you even want to do this? If the water vapor takes up no space at all whatsoever then where does it go? If it takes up space then it obviously never was injected into the airstream or it is in a pool somewhere. It takes up space. Please do go into some detail. Corky Bell makes sense to me and I'd love to learn if there is more to it! I'm not trying to be hostile.

Wankel7

I have heard he disagrees with this idea in his book. Never seen the text. Thank you.

However, I would not call it unreliable. The Aquamist system looks top notch. I have never seen or heard of a failure of that system in my reasearch. WRC uses water injection. That is one type of racing they do not want things to fail. I do agree with the ballpoint syndrome. However, the person who does water injection is most likely not your average put a muffler on it car guy. He/she is willing to take on the added responsibility of the sysyem. Very much like the premixer does

I disagree with Bell's thoughts on it. I cannot offer proof because I do not know enough to speak about it. However, if you do have the time Rotarygod I have a NACA document about Water Injection. Granted, this artical was written in the 30's the things they learned are still true. I can email it to you if you would like.

Maybe he was refering to the fact that it was past his time. WI was in a hayday during WWII when bombers and fighters were using this device for increased takeoff performance and emergency power.

If you do want the artical I will try to copy/paste something to help you/me understand it better.

Also, the reason I would do it would be temporary. Just to do it to see what it does. Of course from a very cautious stance. See what I can learn.

James

ZeroBanger

I have been running WI on my rx7 for the last 8 or 9 months. Trust me it is not reliable. I have had tanks crack, run out of water (thats my fault), fuses broke, hoses pop off, etc. Something always happens. I have solved those issues and for the last 3 months have been problem free, but things happen. EVen aquamist lists pro's and cons and they say that intercoolers are more reliable.

rotarygod

iTrader: (1)

Please do! I'd love to read up on it. Although not in this book he did write elsewhere that the system is outdated and that there are better alternatives. I suspect that is what the implications are. I'm pretty sure he wrote this before the Aquamist system was available so what was around was probably fabbed up at home by people with misc. parts. Good reference to premixing since we have oil in there too! I am nevertheless interested to see your results from the experiment. If it were going to be a permanent type of installation, I would be inclined to put a low water level sensor in the reservior as a safety procedure.

Wankel7

Rotary God - Yeah, I will have it linked later tonight.

Zero - Yeah, the intercooler is by far better in terms of failure. Can you tell me a little about your setup?

James

Wankel7

Ok, try this paper first.

http://www.turboice.net/?documents/t...aper/title.htm

Here is the NACA paper -

http://naca.larc.nasa.gov/reports/1943/naca-report-756/

truespin88

And when I first looked at this... I thought you meant a liquid-air intercooler... :-\

a7r

Anti-WI people always bring this up, but the logic seems flawed. People who are running 'safe' AFRs of ~10.8-12 aren't running them to get more fuel into the mix.. they're running them to cool down the combustion process; which is (from the basic math I've seen) something that water does better than gasoline. So really with WI, you're just displacing fuel that wasn't really adding to the power output anyway,.. which seems like a win to me.

Wankel7

Well said AR7! Thank you.

James

Blowtus

seems like a crazy idea to me. tb mod and lighter flywheel if you're that keen on a bit of throttle response. Dunno why you would be myself...

RICE RACING

Corky licks monkeys ***** !

WI works and its GOLD, anyone who says other wise lines up with **** Head Bell to give monkeys extreme pleasure