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Wet1 · #8 19-03-2005, 02:59 PM

Quote:

Originally Posted by Richard L

Wet 1,

Quote:

Originally Posted by Wet1

Richard,
Thank you for the warm welcome. Interesting site, I assume it is yours (Aquamist). Love the theory and application of WI/AI and was looking for more info online while also looking for yet another alky injection system for my latest project (a SC Z06 Corvette). Looking at your system, I have decided to isn't for me for a couple of reasons, but your forum is very much of interest to me because the world and wealth of knowledge on this topic is relatively small.

As you mentioned, some people are shooting very high volumes of methanol. The more you shoot, the more fuel you have to pull out from the main fuel system. It's no secret that you can make more power on methanol than on gas. The more alky that is injected the more you're converting the engine towards a methanol fuel source (more boost and timing can be added). Most people are not adding anywhere near the volumes you mentioned. I find myself using about 80% pump gas and 20% alky by volume under boost... but keep in mind that you need to add about three times as much methanol as you would gas to maintain the proper A/F ratio. Although I'm injecting 20% alky, it only accounts for about 7% of my fuel source. In other words, if I'm injecting 20% of my overall fuel in the form of methanol, I'd need to reduce the gas required from 100% back to around 93% to keep the proper A/F ratio. So while at first glance it looks like you'd be running "pig rich", you actually are not.

You can use the basic method of tuning you described (ramping up the alcohol flow until the engine bogs down and then ease it back a little) and it will work to get a safe tune with alky or water, but it's far from optimal. I use EGT, KR, and A/F ratio together to nail down the tuning... works great.

If I were you, I would strongly consider make a kit that is compatible with straight methanol so your customers have the option to play with alky. IMO alky offers many of the same attributes as water, but also adds some bonuses (like additional fuel, drastically lower IAT's, increased octane...) You can add WI to a FI engine and it will control detonation quite well, but when you shoot straight methanol you not only control detonation, but you also add power with no other changes.

Designing a system for use with alky is very simple... just make sure everything is corrosion proof and rugged. I don't think your pump will do the job for a high volume alky system. From my experience you need a pump that will handle high volumes, is pressure adjustable, and can't have metal parts in contact with the alky. In the US we have found this pump to be cheap, very rugged, capable of very high volumes, and will do 60 - 180+ psi...
http://www.northerntool.com/webapp/w...&issearch=2687
Add in some SS braided lines, good fittings, and an excellent boost referenced controller and you have magic!

Scot

Thanks for the link, the shurflo pump is ideal for the application as many alky-injection manufacturer uses it, in fact all of them except SMC - pure alky injection. It will surely do the job as a much lower priced and flows more.

As said before the aquamist pump was originally designed for water only. I think in order to design a good water/alcohol injection system, it has to be able to control the flow accurately so one will know the ratio between the gasoline and alcohol or at least predictable. The Aquamist's HSV + the FIA2 or MF2 can easier to adapted for use with alcohol injection/shurflo pump - the HSV seal is made of EPDM and good for most alcohol at high concentration. If you are interested, I can post a schematic on a new thread so it won't alter the thread topic midway.

For your 20% injection rate, it would just be as simple to add 20% of alcohol to your fuel tank to be done with it. If your fear of the leaning up due to the a/f/a ratio, just turn up the fuel pressure a bit to compensate. I remember someone posted this particular method to this board and proved that it is very effective.

The biggest problem facing the usage of alcohol by injecting it as a fuel and not as a coolant - it makes the accurate delivery to each cylinder more difficult especially the log-type manifold/plenum. This critcal factory has to be overcome for a alcohol injection system to be reliable, I suggest the only way to tackle this problem is by using port injection to guarantee even delivery to each cylinder.

Further down the line, the controller that meters the alcohol injection valve has to be mappable and tune exactly as the gasoline injection system. The blockage detection circuitry is also vital since we are offering the system to mostly a DIY market where strict installation procedure is not often followed and debris may be introduced into the alcohol line and blocks one jet. Since alcohol injection is often triggered during boost , one clogged jet can be very bad for the engine.

As I am reasoning my approach to my ideal alcohol injection system, you might as well contact the proper company that supplies the alcohol fuel dragster. It is a subject I know little of and how any alcohol/gasoline engine should be tuned - difficult enough to get tune individually as it is but infinately more complex to tune both with two separate mappable controllers. I think it will be a long time before an aftermarket duel-fuel system is available and the cost? it won't be 399 dollars for sure.

Do you think I am being over-cautious? As hothod has pointed out, WMN has an in-built "fail-safe" mechanism within it. This is the reason I am reading more into the technology as a simple power adder.