Methanol /Water injection

[Super-Cuda]

So guys and Gals,

I participated in a Wheels for Wishes charity for guide dogs this weekend and was parked next to a 2017 Subaru that a young guy had modified.

Great car BTW, Very well done.

What got my attention was it is using Methanol/water injection. The guy tells me that he controls the injection with his boost signal and gains an extra 60 hp with it! It is plumbed into the intake with a feed line from the reservoir and two solenoids.

From what I read so far about it , I can run more timing and not have to worry about pinging even with 11-1 compression and the crap pump fuel we are stuck with here in Canada.

If I am understanding this correctly, I would get more hp by adding a few more degrees of timing plus the effect of higher octane by using a signal from the distributer to activate the system under specific RPM conditions. This seems a very easy way to gain extra hp and make the car much more driveable.

I'm probably missing a lot here , hence the thread.

Looking forward to the comments.

Cheers!!


Here's the kids car BTW....

 

[jaws]

The methanol also cools the charge so you can run more timing and more compression.

 

[MopaR&D]

Do you currently need to run less ignition advance than optimal to avoid pinging? If not then water/meth injection won't do a whole lot. You would want it to be configured to activate based on engine vacuum/load too, not so much RPM.

Engine Masters show on Motor Trend did a test with water/meth injection on a NA engine, it did show small power increases but the engine was already able to run on premium pump gas with optimal timing. The best power increases were also realized with 100% methanol as they found that the water does little for actual power, it just cools and slows the combustion process but the methanol cools as well and has much better detonation resistance. They also had to lean out the AFR a bit as adding methanol effectively richened it overall since it is a combustible fuel. Just food for thought.

You'd also need to keep an eye on your engine oil and possibly change it more frequently as some of the methanol will get past the rings and contaminate it over time.

 

[Kendog 170]

 

[Matts440]

Just be careful and keep an eye on the water/meth level if you are tuning the car to it, if it runs out your air/fuel mixture goes way lean and will fry pistons, did it once by accident. The 100% meth give you a more bang for your buck. Snow has a good kit and there are others out there, jet size will depend on the engine, can also be ran off a micro switch like NOS if you don't have a vaccum/boost controller.

 

[AJ/FormS]

David Vizard has a great video on this, and he goes into a lotta detail in his presentation.
However
I have run up to 11.3 Scr in my alloy headed 367, on 87E10 since 1999, with no ill-effects, even with full timing, which with the alloy heads is 32>34 degrees. The Engine now has well over 100,000 miles and is still going strong.
The point is this; a high Scr is not your enemy.
It's the Dcr that you need to watch, and
more than anything, it's the cylinder pressure.
Well, actually it's the heat of combustion, and keeping the exhaust valves cool.
As member @MopaR&D mentioned, water injection is a means to an end. If your engine is Not detonation-limited, nor boosted, there is not much if anything to be gained from it, except a cleaner combustion chamber; and, more likely is, that your engine will lose power if the system is not set up right.
The increase in Power will come from the increased cylinder pressure that you can run with the ignition and fuel systems optimized.

If your current combo has drivability issues, and you have a manual trans with 3.55s or less, Ima guessing yur running too much initial timing, and your rate of advance is too quick.
I ran into this with my hi-pressure 367 which in this configuration made too much power below 2800 rpm at part throttle, and driving it in that zone, it was difficult to modulate the power at small throttle openings.
I solved this by using less initial timing, a slower curve to 2800, and then getting it all-in by 3400. To compensate for the loss of part-throttle and cruise timing, I modded my vacuum advance to get 22* and I bring it in as fast as possible.
And finally, I run a 3.09 low gear in the trans, which with 3.55s out back, takes off like it has 4.10s. This cured most of the issues.
To drive real slow, I retard the timing down to 5*, with a dash-mounted, stand-alone, adjustable, timing box, that has a range of 15 degrees. I have it set to retard up to 9*/advance up to 6*. By retarding the Idle-timing, this decreases the idle-power even more and lets me drive down to 3.5 mph in gear, and NOT toeing the clutch, and without any jumpiness. And it allows me to increase cruise timing an additional 6*, for increased fuel-economy.
For a while, I had a Thermoquad spreadbore on her, with the tiny primaries, which helped some as well. But for me, it was not quick enough to open, until it was too quick, and so, I switched to a Holley750DP, which is tirespin on demand; and is much more modulate-able in power application in the corners, for funtastic Second gear drifting.. right around the torque-peak .
BTW
I find no fault with Manitoba's 87E10. My 367 has gone 93mph in the Eighth, on that so-called "crap pump fuel"..
Hint; there's already up to 10% alcohol in it.

I can't speak to automatics nor to BBs, cuz I don't run them..... lol.

 

[TT5.9mag]

No chance in hell he’s picking up 60hp with water meth injection. Maybe, and it’s a big maybe, on a 700hp combo and running straight methanol you could see that much but it would have to be a situation where intake air temps were horrible prior to injection. It’s not nitrous. It is a way to add detonation resistance and should be used that way. Do some research before spending your money.

 

[MopaR&D]

No chance in hell he’s picking up 60hp with water meth injection. Maybe, and it’s a big maybe, on a 700hp combo and running straight methanol you could see that much but it would have to be a situation where intake air temps were horrible prior to injection. It’s not nitrous. It is a way to add detonation resistance and should be used that way. Do some research before spending your money.

OP didn't specify but it may have allowed the Subie guy to safely bump up his boost to gain that 60 hp. Those engines are made of glass after all, they don't handle much boost over stock without blowing head gaskets and breaking ring lands. SuBiE lIFe brUH!

 

[TT5.9mag]

I was at a gas station by my house a year or so ago, guy pulls in driving a rowdy sounding STI. So naturally I go look at it and start asking questions. Tells me it makes 740 to the tires. I called bullshit and he laughs and says get in. Long story short, I was wrong. One of the faster street cars I’ve ever been in.

 

[Super-Cuda]

OP didn't specify but it may have allowed the Subie guy to safely bump up his boost to gain that 60 hp. Those engines are made of glass after all, they don't handle much boost over stock without blowing head gaskets and breaking ring lands. SuBiE lIFe brUH!

I'm pretty sure that's exactly what he did. He has dyno sheets that show 400 + to the wheels.

Appreciate all the comments and info though as I am not very knowledgeable on the topic .

 

[TT5.9mag]

With water meth you quickly get to the point of diminishing returns. It does cool the iat similar to a good intercooler, and the engine will make more power at the same boost level. But only slightly. As you add more water and meth the temps stop dropping and the power stops rising and nothing you can do will bring it back. Water doesn’t burn. Steam doesn’t burn. What it does is take up space in the combustion chamber that could be occupied by fuel, which makes power. Which is why straight meth is so much better. It’s latent heat of vaporization is high (which pulls tons of heat out of the air) and it is a burnable fuel. But it will change the tune up drastically. You have to remove gasoline as you go up in meth to keep the afr happy. Which goes back to what @Matts440 said, don’t run the tank dry. On an NA engine my opinion would be the juice just isn’t worth the squeeze.

 

[MopaR&D]

I was at a gas station by my house a year or so ago, guy pulls in driving a rowdy sounding STI. So naturally I go look at it and start asking questions. Tells me it makes 740 to the tires. I called bullshit and he laughs and says get in. Long story short, I was wrong. One of the faster street cars I’ve ever been in.

Oh they can be built up to be nasty quick for sure but you'll be doing it with pretty much entirely aftermarket parts. Should've asked him how much it cost lol. That Mitsu engine was iron block with beefy crank and rods from factory and the Evo had AWD like the Soobs, big rivalry between the two particularly in rally racing. 4G63 engine was also used in the 90s-2000s Eclipse/Eagle Talon. Not that it really matters in this context I just remember Colorado being infested with Subaru fanbois and they were insufferable d-bags so I rip on them whenever I get the chance lol.

 

[Matts440]

N/A cars it is a gamble on hp increase, mine was on a boosted SRT 4 neon and it did help until it didn't like running out. Plus distribution on a NA classic engine would be interesting for set up unless you use a nitrous plate and get the right smaller jet size, but have to weight the real gains over the expense. 100% method was way more fun then the mixture plus different brands have different % mixture in them as well meth to water ratio.