Water/Methanol Injection

[TiredGXP]

Of course I'm speaking of water/meth install on an engine as a benefit, not to treat an already knocking engine. It doesn't matter how well it works, several people on the Fiero forum still refer to it as a band aid partly because that's what Corky Bell called it decades ago.

I was kind of surprised at his attitude on water injection. Floating around the net somewhere is a pretty good engineering paper describing the development and testing of water/alcohol injection for use in aircraft engines during the second world war.

The benefits seemed to be quite plain.

i would still have an I/C, even with the mention of a backfire lighting a pool of water/meth stuck in the IC even though the chances are slim to none considering the heat and airflow.

it never hurts to have colder air in a boosted application. the restriction an IC is can't hurt more than it helps, so long as it has sufficient airflow.

it's almost possible to cool it down to ambient if you use two or three stages of water/methanol and a good, well-thought out air-air I/C.

as for the fiero forum: same effect that people have when reading religous texts, just people interpretting it differently. to me, when i read maximum boost, corky is saying that water injection is a poor excuse for proper fuel tuning. that's what i get out of it anyways.

It is very rare and with a properly sized nozzle highly unlikely given it is pretty much evaporated by the time it leaves the compressor. The system would have to be pretty poorly setup to allow any puddling ahead of the intercooler given air moving past any puddle is going to have an evaporating effect.

From what I've been reading water/meth will provide equal to or more performance increase on the same setup as a proper inter cooler. I read on snow's forum where water/meth injection is offering as much or more benefit by itself than an air to water intercooler which has the potential to provide greater than 100% cooling efficiency according to a couple of race car owners on the forum who are using it in place of their air/water intercoolers.

I have a front mount intercooler in my Fiero and I'm at about 90% efficiency. I'm sure my water/meth kit will provide greater benefit than that with a combined cooling effect and octane boost with a single nozzle. I'm going to install an additional temp sensor ahead of the intercooler and datalog temps under boost before and after the intercooler with the use of dual nozzles.

If the temp difference is negligible then the intercooler would only serve as a backup in the event the meth system failed and would also reduce efficiency due to the 1 or so psi lost due to resistance through it.

I would be able to eliminate additional intercooler related plumbing as well as recover the lost boost pressure through the intercooler that results in more exhaust back pressure to reach the desired boost. I might run a solid meth injection system and no intercooler if the results prove correct.

[robertisaar]

i would still have an I/C, even with the mention of a backfire lighting a pool of water/meth stuck in the IC even though the chances are slim to none considering the heat and airflow.

it never hurts to have colder air in a boosted application. the restriction an IC is can't hurt more than it helps, so long as it has sufficient airflow.

it's almost possible to cool it down to ambient if you use two or three stages of water/methanol and a good, well-thought out air-air I/C.

as for the fiero forum: same effect that people have when reading religous texts, just people interpretting it differently. to me, when i read maximum boost, corky is saying that water injection is a poor excuse for proper fuel tuning. that's what i get out of it anyways.

while it has good results, it depends on how it's used.

if someone is having a lot of fuel leaning/detonation issues and figures water/meth injection is the answer, it's wrong. they're fixing the problem by adding another variable. simplicity is our friend.

someone who CANNOT fit an intercooler, cannot fit a large enough intercooler, or NEEDS the extra temperature drop and cannot achieve it in another fashion, that's a correct application.

Look over the Grand National link, the dual nozzles are working so well that he has removed his intercooler and that car has plenty of room for a large one. The air is being cooled twice where an intercooler only does it once. The best an air to air intercooler can do is get you closer to 100% of ambient temps with some restriction. Water/meth on the other hand apparently goes one step further than that by providing at a small cost to none if you use water, an increase in octane rating in addition to reducing inlet air temps and increasing boost due to the quenching effect as opposed to the loss in boost you would get from restriction of air flow through an intercooler.

There is a net effect with the addition of dual nozzles that is apparently equivalent to or greater than what the intercooler alone is offering on a street car if I read closely enough about the GN.

Of course I'm speaking of water/meth install on an engine as a benefit, not to treat an already knocking engine. It doesn't matter how well it works, several people on the Fiero forum still refer to it as a band aid partly because that's what Corky Bell called it decades ago.

[robertisaar]

Some members on the Fiero forum refer to water injection as a cheap band aid. How redicuolous is that considering the results it produces at such an exceptionally low expense.

while it has good results, it depends on how it's used.

if someone is having a lot of fuel leaning/detonation issues and figures water/meth injection is the answer, it's wrong. they're fixing the problem by adding another variable. simplicity is our friend.

someone who CANNOT fit an intercooler, cannot fit a large enough intercooler, or NEEDS the extra temperature drop and cannot achieve it in another fashion, that's a correct application.

I'm really damned impressed it didn't start knocking when the afr's went into the 14's. That water injection must have really helped. Hope to hear the results with the better fueling soon.

I've been doing quite a bit of reading on water/meth injection and aside from the traditional install benefits there's more to be had with dual water/meth injection by adding an additional injector just ahead of the turbo although this is an S/C engine. It pre cools the compressed air by evaporation inside the compressor housing for added air density in addition to what occurs just ahead of the throttlebody and in the combustion chamber.

There has been concern about compressor blade damage but it has been proven that as long as the mist contains less than 18 micron droplets there's no problem. This requires the injector nozzle to be placed close to the compressor blades (inches) for a direct path because it prevents the puddling that occurs when a long indirect distance is present allowing for large droplets to develop on inlet plumbing and then hit the compressor blades. It's also less likely to happen in that circumstance when a water/meth mix is used instead of straight water due to a lower specific gravity.

I know they're not exactly the same principle wise but look what it does for the little diesel engines:

http://forums.tdiclub.com/showthread.php?t=209796

and here's a GN user that's in progress:

http://www.turbobuicks.com/forums/alcohol-propane-nitrous/78800-preturbo-injection-test-run-setup-2.html

The most impressive point comes about when you're making a lot of power off a small amount of boost and when you can significantly increase performance on the same amount of boost. We use a lot of old technology standards when addressing performance, but engines built 10-15 yrs ago are not as efficient nor the metals back then as strong as what we have now. We still use the same bsfc numbers in our calculations that were used on those engines and that can't be right given the hp/litre ratios we have now.

Some members on the Fiero forum refer to water injection as a cheap band aid. How redicuolous is that considering the results it produces at such an exceptionally low expense.