Water/methanol injection (1 Viewer)

[Adam B]

Home Depot sells "Turbo Washer Fluid", consists of 49% Meth/51% H2o, $2.99 for 3.78L jug, no mixing required.

That's the stuff I use now. I share my washer fluid reservoir with the meth system so I get more than 4L capacity and can still wash my windows. 4L lasts me from Vancouver to Kamloops with heavy use on the big hills. I use about $70 in diesel and $3 in washer fluid so I'm not too worried about the cost of consumables. Even if you do mix your own 50/50, 4L of methyl hydrate (methanol) is $10 so a mixed jug would be $5. Again, the added cost is negligible. If I cared about that I'd ease off on my right foot a little and get better mileage.

I think my system was around $400? Can't remember and don't feel like looking it up any more. Basic Snow Stage 1 Diesel system bought through PDR.

 

[CycloSteve]

Thread revival!

I have a Devils' Own kit from my Audi which is no longer in use, and considering using this on my 1HD-FT with G-Turbo Grunter Extreme. The unit has a MAP based 2.5 Bar variable/progressive controller, which can start injecting as low as 2.5psi, and max out as high as 20psi. This fits pretty well with the boost levels I am seeking with my motor/Turbo combo.

With the 45 there is no more room for an AA intercooler, nor a WA radiator...having a functioning A/C was more important. That said, some sort of cooling of the air charge would be nice. Other than getting a larger injector for the kit, it is already paid for and works.

Interested in hearing about other Mudders who are using W/M for their TD cooling, and any pitfalls or long term problems.



Steve

 

[Dougal]

With no intercooler you're screwed. You reach a point with increasing boost where even though density increases and A/F ratio increases, you can't make head-way on EGT.

I just can't believe there is no room for a water to air intercooler.

 

[CycloSteve]

The 45 is a whole different beast from the 80...there is literally no room between the AC condenser and the grill, and mounting anything low is just asking for disaster. W/M is essentially chemical intercooling; as CDAN would say WWII fighter style.

I am shooting for 20psi max with my turbo, and the truck weighs in about 2000 pounds less than an 80, so I have that in my favor. Have an EGT which will go pre-turbo, and likely will also have a bung welded into the exhaust for a wideband O2 sensor for AFR data-logging purposes.

Once the engine is actually running, we will start messing around with the W/M pump pressures to fine-tune the system, basing changes on real-world data.

For those who have or are running W/M, I am definitely interested in hearing your experiences with the Toyota Diesel motors...all of my use so far has been on turbo and supercharged gassers. Nozzle size, placement, dual vs. single, etc. are all to be determined.



Steve

 

[Dougal]

The 45 is a whole different beast from the 80...there is literally no room between the AC condenser and the grill, and mounting anything low is just asking for disaster. W/M is essentially chemical intercooling; as CDAN would say WWII fighter style.

On some WW2 fighters water injection was used to suppress detonation and allow the engine to survive more boost.
That has no application on a diesel. We have no detonation.

Chemical intercooling is a completely misleading term. But with 20psi boost you'll be able to run ~20:1 A/F without EGT getting too hot anyway.

 

[crushers]

it has to do with cooling the charge, not the EGTs. after 14 psi the charge of compressed air is heated to the point that the volume of air is affected(expanded). once the charge is expanding adding even more boost amplifies the problem. cool the air and more condense volume of air can be compressed and shot into the cyl. the lower EGTs is just a nice side result.
W/M, although i don't agree with the practice, does achieve this somewhat.
of course a properly calculated turbo for the desired results is the best way to proceed. having too small a turbo and high boost results in a fast spooling, hot running engine (without an intercooler). great for off road or around the city. having a large turbo will result in lower EGTs on the highway, lower boost needed but won't be as much fun to drive in low speed situations.

 

[cruiserdan]

On some WW2 fighters water injection was used to suppress detonation and allow the engine to survive more boost.
That has no application on a diesel. We have no detonation.

I was under the impression that diesel is detonation.

 

[GTSSportCoupe]

I've run methanol/water injection on a supercharged gasoline engine before, and now am planning a 'stage 1' system for my 2lte. I'm totally sold on the concept. I'll be using it primarily when I'm towing my camper in summer for a little help up the hills.

My understanding/experience is:

- The methanol evaporates in the hot intake plenum immediately after injection. Evaporation requires energy (heat). Thats why you get cool when your sweat evaporates. So essentially the methanol does 'chemical intercool' the intake charge. A cooler charge will impact EGT's much the same as an intercooler. Cooler air at the same boost is more air.

- The methanol ignites when the diesel ignites. Methanol is added fuel. Added fuel means more power. More fuel means more heat, so this will offset the EGT reducing characteristics.

- The water doesn't evaporate much in the intake plenum. Rather the water evaporates during the compression stroke in the cylinder. Again, evaporation consumes heat. This means the water is actually cooling the cylinder during compression. This will reduce EGT's further.

- The water/methanol also have a cleaning effect from the point of injection, and essentially steam cleans the cylinder internals.

- Always inject after the intercooler, otherwise you'll be reducing your intercooler's efficiency. (Intercoolers are most efficient with the largest temperature difference between ambient and intake charge).

- It takes a bit of playing to balance the methanol/water mix and volume for reduced EGTs, increased power, and no quench of combustion. The methanol and water each have their own effect, so finding the right mix for your application is important.

 

[gerg]

I think Dan you are pointing at auto ignition rather than detonation. Diesels run on auto ignition and I have yet to ever hear of diesel detonation. Detonation is a whole bunch of fuel exploding at once rather than burning at a fast rate. As the flame front travels through the cylinder, in cylinder temps increase. If the temps get high enough the whole air fuel mixture reaches a critical mass ( sounds cool), and will ignite all at once rather than waiting its turn. As we all know, detonation often is destructive as it creates abrupt and violent spikes in cylinder pressure. Detonation usually happens after ignition in gas engines, not before like you might think, that is pre ignition. Detonation creates a specific resonance to which knock sensors are sensitive to. I've never heard of an engine that ran on detonation other than the Lockheed skunk works mythical pulse detonation engines.

 

[cruiserdan]

Thank you for the explanation. I've only had my Cummins for 25 years. One would think I would know that by now.....

 

[gerg]

Yes methanol is a fuel, but always remember that you engine is timed for peak cylinder pressure at or around 14 ATDC. If you get enough meth in there (would take lots) it can pre ignite and be counter productive for power. Fortunately methanol requires quite a rich mixture to support combustion and also has a very high auto ignition temp which makes it pretty much the safest of all the fuels to fumigate into a diesel. It also creates water in its combustion which will further cool your egts

 

[gerg]

It's ok Dan. The more I learn about fuels, the more blown away I am at how cool and wildly complicated it is. Fumigating fuels really only gets dangerous if you start getting close to their lower flammability limits. Then all bets are off.

 

[Dougal]

It's ok Dan. The more I learn about fuels, the more blown away I am at how cool and wildly complicated it is. Fumigating fuels really only gets dangerous if you start getting close to their lower flammability limits. Then all bets are off.

Actually. Flamability limits are only applicable to atmospheric temperature and pressure.
I've shown with LPG fumigation in my own engine that detonation can occur at ~1/5th of the lower flammability limit.
As far as I'm concerned, anytime you're over the auto-ignition point you can expect combustion in an engine. Regardless of concentrations.

The only fuels which can be safely fumigated are those with a high enough knock resistance. For diesel engines that is methane gas (CNG) and not much else.

I have no idea what Crushers is on about. I don't agree with any of the ideas presented in his post.

 

[Tapage]

With 0 ideas to share .. only my experience using W/M in both of my Toyota TDI engine ( one DI and one IDI ) for more than 4 years now ..

The more close I ran to 50% alcohol / methanol ( ran both ) the more power I archive .. ( no EGT reduction or variation from just diesel and I have plenty in both engines ) the less % of alcohol / methanol the lower EGT ..

 

[GTSSportCoupe]

With 0 ideas to share .. only my experience using W/M in both of my Toyota TDI engine ( one DI and one IDI ) for more than 4 years now ..

The more close I ran to 50% alcohol / methanol ( ran both ) the more power I archive .. ( no EGT reduction or variation from just diesel and I have plenty in both engines ) the less % of alcohol / methanol the lower EGT ..

What size injector are you using?

 

[Tapage]

What size injector are you using?

Both 01 pre turbo and in Tencha ( IDI ) 03 and 05 for Marilu ( DI )

 

[gerg]

I forgot about that test you did Doug. Methanol is about 3times higher for lower flammability limit than propane...roughly. What cc/min with 50/50 water meth would you think would be a danger zone for a motor. Say a 4l pushing 15lbs boost? Might give folks a rough idea of something to stay well away from. Diesel of course.

 

[Dougal]

I forgot about that test you did Doug. Methanol is about 3times higher for lower flammability limit than propane...roughly. What cc/min with 50/50 water meth would you think would be a danger zone for a motor. Say a 4l pushing 15lbs boost? Might give folks a rough idea of something to stay well away from. Diesel of course.

I'm not even playing the recommendation game with water/meth. head-gaskets aren't fun things to change.

 

[wrongway around]

I'll stick with the wd40 for my potato gun thanks. Gturbo not enough? Na I'm not jealous.

 

[ForealBoreal]

I'll stick with the wd40 for my potato gun thanks. Gturbo not enough? Na I'm not jealous.

Still dreaming of 35lbs of boost, 14mm pump, bigger airbox and intercooler?