Alcohol substitute methanol?

[Casper_gt2]

Alright so I feel like this is a dumb question but im honestly curious. I was watching a video on methanol and this guy said this he uses alcohol from his local cvs since it's hard to get meth in Hawaii. Do people alcohol use rubbing alcohol as a substitute with no problem?

 

[oddball]

It'll burn, if that's what you're asking. Both alchohol and methanol can be a real PITA.
Anything over-the-counter isn't meant for use as fuel so there's other junk in there. That other junk can cause other problems, like degrading rubber or leaving deposits or whatever.

Alchohol and Methanol burn differently, so I'd be hesitant to switch without having a really good idea about the difference and setting up the injection system to account for that. Most people end up using windshield washer fluid as their meth source, or the special bottled fluids from the injection supplier. I'd want to chat with them about running alchy before doing it.

Methanol is usually preferred because it absorbs much more *heat* when evaporating, so that helps high boost engines get a cooler charge. In the Stinger case we're actually using it as a fuel supplement because it's hard to get enough fuel out of the direct injection system when running at the edge. Here, methanol also has more power density than alchy.

If you're dancing on the edge then that difference in power density can cause a lean mix unless it's jetted appropriately.

As always, no warranties, it's up to your experimentation and tuning.

 

[Casper_gt2]

It'll burn, if that's what you're asking. Both alchohol and methanol can be a real PITA.
Anything over-the-counter isn't meant for use as fuel so there's other junk in there. That other junk can cause other problems, like degrading rubber or leaving deposits or whatever.

Alchohol and Methanol burn differently, so I'd be hesitant to switch without having a really good idea about the difference and setting up the injection system to account for that. Most people end up using windshield washer fluid as their meth source, or the special bottled fluids from the injection supplier. I'd want to chat with them about running alchy before doing it.

Methanol is usually preferred because it absorbs much more *heat* when evaporating, so that helps high boost engines get a cooler charge. In the Stinger case we're actually using it as a fuel supplement because it's hard to get enough fuel out of the direct injection system when running at the edge. Here, methanol also has more power density than alchy.

If you're dancing on the edge then that difference in power density can cause a lean mix unless it's jetted appropriately.

As always, no warranties, it's up to your experimentation and tuning.

Thanks for the detailed reply, I'm not gonna switch, I just found it interesting. But I had a problem come up yesterday with my bms nozzle. It's not misting anymore, it's more of a aggressive stream and it's causing my car to not run correctly while on meth. Would you know how to clean it?

 

[Volfy]

Rubbing alcohol is typically just 70% isopropyl alcohol (IPA). Those of you remember your HS chemistry will note the namesake means it has 3 carbon chains, ethanol has 2. Methanol has 1. They are all alcohols. IPA, and sometimes ethanol, are used for medical purposes because they are less toxic to humans than methanol (wood alcohol). Yes, rubbing on your skin does mean some of it is absorbed into your system.

Can it be used in your CPI system meant for methanol? Yes. The caveat being the common over-the-counter 70% IPA has 30% water. There is hardly any other "impurities" in it. The water content is itself not harmful. In fact, it can be just as beneficial in reducing incoming charge air temp. Water has by far the highest latent heat of evaporation, compared to any of the e alcohols mentioned, and much more than gasoline. So it has the potential of having the highest effect of cooling intake air temp (IAT). The problem with water is its low vapor pressure, which is just a fancy way of saying water doesn't evaporate as readily as the alcohols. Realistically, this might be more of an issue in the colder months, when ambient air temp is very low, and so liquid water gets too lazy to flash into gaseous phase. Summer time... when it's hotter than Hades, not a problem.

In fact, back in WWII, fighter and bomber engines quite often use water injection to boost power. So it does hold merit.

As long as your CPI system plumbing is okay with water content, you're okay. I would imagine it should be. Since any alcohol - including methanol - is very hydroscopic and will draw moisture from the air, that means if you let the methanol sit for any length of time exposed to ambient air (especially if you live in the warm humid South) you are already injecting a mixture of alcohol and water.

BTW, sometime 90% IPA is available over-the-counter. I've even seen 99% IPA occasionally. Although, how accurate that really is is anybody's guess.

 

[oddball]

Fun fact: methanol injection is usually 50% meth, 50% water.
Water isn't great at burning, so water vapor in the intake charge takes the place of something that would burn. It's benefit in cooling is balanced against that. I always found the airliner turbine engine water testing to be fascinating - turbines can swallow an amazing amount of water and keep running. Piston engines aren't as forgiving.


As for cleaning the injector - no idea. Probably just remove it and spray some throttle body cleaner and/or brake cleaner through it.

 

[Volfy]

Water injection was often used in WWII, primarily because a lot of the warbird engines used enormous air-cooled radial engines with staggered multi-row cylinders, some of which had notorious cooling issues. Back then, some of the German aircraft engine had mechanical fuel injection systems, but the Allies were still carburetors only. With none of the sophisticated sensing & feedback controls we have these days, overheated cylinders posed a great risk for detonation. This is especially true on take off, with huge bomb loads, low air speeds, and warm ambient air temp near ground level. Once they climb up to cruising altitude, intake air is much colder, air speed is higher, so cooling was less an issue.

It was so bad that some of the bombers, earlier in their service life, were said to have suffered as many crashes due to overheated engine exploding on takeoff as they did due to enemy fire.

Water injection was an relatively easy-to-implement anti-detonation strategy. It was sometimes referring to as boosting engine power, which is true in the sense that it helped the bomber pilots apply more power without fear of blowing themselves to smithereens.