Questions regarding FAV
 

I would be interested in using an Aquamist FAV, but not a complete Aquamist system.

Thus, I have some questions regarding use of the valve.

Car specs:
1985 Pontiac Fiero 3.2L V6
turbo, non-intercooled
MegaSquirt 2 programmable fuel injection (controlling the FAV directly)
Injection 5" from the intake valves, via 6 check-valved nozzles
Pressurized water/methanol tank (compressed air) (not sure I trust those diaphragm pumps)



From the FAV web page, it says: "Always use 99% methanol". Is it acceptable to use the FAV with water?

With regards to hydrocarbons, is the FAV really that sensitive? If I am drilling/tapping the water/methanol reservoir, will even cutting fluid residues damage the FAV?

How do I choose between the 1300 cc and 1600 cc FAV for my application? What are the differences?

I have read this thread: http://www.aquamist.co.uk/forum2/vbu...ead.php?t=2922
what limits the PWM frequency to 30 Hz?
I was thinking of controlling the FAV like a standard port injector; one pulse per two crankshaft revolutions.
However, with a 6000 RPM redline, the valve would be working at 50 Hz.
Is the opening time a limiting factor? If I use a peak-and-hold driver, can I reduce the opening time?
Can I clamp to a voltage higher than 75 V to close the FAV faster?

Is the speed of the FAV influenced by the supply pressure?



...and not really FAV-specific, but more generally regarding water injection:
From the HFS3-v3.1 page, I saw the following recommendation:
"100% water: 10-15% water/fuel ratio or 0-5-1cc per BHP"

From NACA Report 756
Low octance fuel: tested up to 1.5 water/fuel with good results
High octane fuel: tested up to 0.6 water/fuel with good results

Why do you recommend such low water flow compared to Report 756?

Re: Questions regarding FAV
 

From the FAV web page, it says: "Always use 99% methanol". Is it acceptable to use the FAV with water?
It meant 99% pure methanol. Water is fine. Some model airplane methanol contains 20% castrol oil.

I am unable to discuss the FAV specs as it contains too many proprietary information.

Re: Questions regarding FAV
 

Hello Richard,

Perhaps I should explain myself a little better.

I'm not a competitor or anything like that; I'm a Saturday mechanic who wants to purchase your product to install it in my car.

I just want to know if the FAV will work for me before buying.

In my engine build, I'm at the point of machining my intake manifold and setting orifice sizes. The orifice sizes will depend on the duty cycle capability of the valve at my desired RPM. I can't easily change the orifices without removing the manifold from the engine.

So I don't want to know internal details; I just want to know how to use the valve.

I can characterize the flow by sending different pulse widths/frequencies to the valve, but I'll be wasting my time doing an exercise that has already been performed. Anyone can do this with a valve in their hands, so I don't see why this information needs protecting.

Until I get this characterization done, it's going to hold up my intake manifold machining. I might even discover that my direct-port water injection scheme doesn't work at all, and I'll have to rethink the project...

Like anybody, I am hesitant to make a purchase unless I know it has a good chance of working for me; I don't want to throw my money in the drain.

Good customer service is good; happy customers get the word around.

Patrick

Re: Questions regarding FAV
 

Feed 12V PWM @25-30Hz with 55-75v clipping. That is all.