While discussing the problem of carbon buildup on valves in GDI engines and the way to possibly eliminate or mitigate it I started to wonder. I know some folks inject a methanol under pressure for some power gains under throttle. As a side effect it seems the methanol cleans or delays the carbon deposits endemic in GDI engines. I have no real interest in the power gains but wonder if it would be possible to educt methanol on the intake plenum after the MAF. I am talking a small amount and hopefully something close to a vapor for carbon cleaning purposes . For continuous use. Will it work? any ideas?
Passive methanol injection
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Any induction through a modern dry manifold design is going to be uneven from cylinder to cylinder unless you use multiple points evenly around the cylinders. My opinion is if it offered any real benefit someone would be doing it already.
Originally Posted by SteveSRT8
Any induction through a modern dry manifold design is going to be uneven from cylinder to cylinder unless you use multiple points evenly around the cylinders. My opinion is if it offered any real benefit someone would be doing it already.
I don't agree.
Any induction through a modern dry manifold design is going to be uneven from cylinder to cylinder unless you use multiple points evenly around the cylinders. My opinion is if it offered any real benefit someone would be doing it already.
I don't agree.
Originally Posted by Mainia
Originally Posted by SteveSRT8
Any induction through a modern dry manifold design is going to be uneven from cylinder to cylinder unless you use multiple points evenly around the cylinders. My opinion is if it offered any real benefit someone would be doing it already.
I don't agree.
As long as the methanol is injected close to the throttle body I agree with Mainia. These days, where every last HP is sought after, as well as emissions, I guarantee great pains are taken with intake manifold design to get cylinder distribution as close to equal as possible. As long as the methanol is injected close to the throttle body and effort is taken to allow it to atomize and not puddle I see no problem.
I have looked into doing this as well on my Regal GS because I know of a few other owners that have done it for more boost, more power, etc and the moral of the story was that it made very little, if any, noticeable difference as far as intake valve deposits.
Originally Posted by SteveSRT8
Any induction through a modern dry manifold design is going to be uneven from cylinder to cylinder unless you use multiple points evenly around the cylinders. My opinion is if it offered any real benefit someone would be doing it already.
I don't agree.
As long as the methanol is injected close to the throttle body I agree with Mainia. These days, where every last HP is sought after, as well as emissions, I guarantee great pains are taken with intake manifold design to get cylinder distribution as close to equal as possible. As long as the methanol is injected close to the throttle body and effort is taken to allow it to atomize and not puddle I see no problem.
I have looked into doing this as well on my Regal GS because I know of a few other owners that have done it for more boost, more power, etc and the moral of the story was that it made very little, if any, noticeable difference as far as intake valve deposits.
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Hands up everyone here who has ever seen first hand what happens when fuel is injected into air in an inlet manifold...before, after, near after, and a long way away.
Bonus points for if it was your engineering thesis.
Thoughts and feelings at the door please
Bonus points for if it was your engineering thesis.
Thoughts and feelings at the door please
There are a lot of aftermarket charge pipes which have a bung hole for meth/water injection. I suspect the demand for such a product will continue to decline along with the continued decline in DI carbon buildup related issues.
I was actually thinking of a more passive system which would draw as a vacuum some small amount of methanol continuously. The eductor would need some engineering and have to be in the plenum after the air filter but close to it for the vacuum effect. Probably not going to wok well as the methanol would need to turn gaseous to be drawn with the airflow. I'm a little concerned how the MAF would react to the methanol if it was introduced prior to the sensor. Some engineering challenges here.May not work or be feasible.
This works and has been proven over and over again on many independent dyno tests. Look up SNOW water/meth injection. They pioneered the idea.
It is especially useful in supercharged/turbocharged applications as it not only cools the intake charge but also raises the octane some.
It is especially useful in supercharged/turbocharged applications as it not only cools the intake charge but also raises the octane some.
The dry manifold issue can be negated to a large extent with greater atomization of the liquid being injected. A proper nozzle does a much better job than a typical port fuel injector with atomization.
This is something that has been completely overdone over the past 20 years. When done right, there are no deposits on either the valves, combustion Chambers, or pistons. Pulled apart plenty of engines running these systems. They are used in plenty of tunes that would never survive a minute without them. If there were a cylinder-to-cylinder disparity great enough, that cylinder would be destroyed.
The biggest problems with these systems are that almost all of the commercial systems are overpriced garbage, and none of them have appropriate fail-safes. If a system malfunctions, it can hydrolock a motor and destroy it. The only really good kits are custom made to spec with all of the necessary fail safes.
This is something that has been completely overdone over the past 20 years. When done right, there are no deposits on either the valves, combustion Chambers, or pistons. Pulled apart plenty of engines running these systems. They are used in plenty of tunes that would never survive a minute without them. If there were a cylinder-to-cylinder disparity great enough, that cylinder would be destroyed.
The biggest problems with these systems are that almost all of the commercial systems are overpriced garbage, and none of them have appropriate fail-safes. If a system malfunctions, it can hydrolock a motor and destroy it. The only really good kits are custom made to spec with all of the necessary fail safes.
Been done for years. Yea, you cannot put it in the fuel because you would be negating fuel to inject that. But injecting a water/methanol mix is harmless to almost any engine when done right.
Methanol on its own has inherent flashback issues as well as material compatibility issues, which is why it's not used as a gasoline blending agent. A methanol / water mixture added to gasoline would result in guaranteed phase seperation.
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I'm not sure about a GDI car, but I sprayed a mixture of 80% M1 methanol and 20% distilled water through two small nozzles at 300 psi on my turbo car. It was set to come on only when boost pressure exceeded 5 psi. When I pulled the head off after a year of use, the piston tops, chambers, valves, and ports were all squeaky clean. I sprayed just enough to drop my air/fuel ratio at wide open throttle from 12.2:1 to 11.6:1. It made a huge difference in intake air temperature. The clean chambers was a nice bonus.
Suprised no one has mentioned the Corvair Monza turbo flat six and Olds with the 215 cu inch aluminum V8 turbos were cooled with methanol/water injection systems that was used to control detanation back in the early 60`s.
Originally Posted by Brigadier
My owner's manual says to NEVER use methanol in the fuel. So I don't think that would work well, injecting it into the manifold,,,
The fuel system components are resistant to ethanol for use with E10 but not methanol.
Injecting methanol separately would make this a non-issue as it would never pass through the fuel system.
My owner's manual says to NEVER use methanol in the fuel. So I don't think that would work well, injecting it into the manifold,,,
The fuel system components are resistant to ethanol for use with E10 but not methanol.
Injecting methanol separately would make this a non-issue as it would never pass through the fuel system.
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