I know this is outside your project range, but what would be great is a direct injection water system that would inject late in the combustion stage. This would cool the exhaust gas and since the expansion coefficient for water is so large, should gain some torque. I'm pretty sure this was done on earlier diesels, not sure why it was abandoned.

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For Sale: 1982 MB 300TD
1995 Chevrolet Suburban 6.5TD

Sold: 1980 IH Scout Traveler- Nissan SD33T Diesel

But did it lower the egt's?

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Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.

Not at all. 300cc was not enough, I needed closer to 500-600cc

I would wonder if cooling the combustion environment before the exhaust valve opened would cause a vacuum to form and rob power/break things?

I think this direct H20 injection thing might make more sense if there was an extra compression stroke added specifically for the water injection event, in which case the glowplug holes might be a good place to stick injectors for a common-rail water setup.. run the cam at 1/3 engine speed instead of 1/2... read: Crower 6-stroke... speaking of which, does that thing even work?

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99 E300 Turbodiesel 100k

Here's a link to a paper concerning Water Injection (WI). http://homepages.cae.wisc.edu/~rutland/research.dir/NOx_water/2000-01-2938.pdf These researchers were primarily concerned with reducing emissions, but found that fuel consumption was reduced in some cases (increased in others). Its been a while since I read it, but I'm pretty sure that the water injection timing was not altered (went in right after fuel). I think that this would be a huge factor. Yes, WI would necessarily reduce the temperature, but the expansion ratio of water is huge. So, for limited amount of water you would increase post combustion pressure while reducing NOX production. Too much water will of course reduce pressures.

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For Sale: 1982 MB 300TD
1995 Chevrolet Suburban 6.5TD

Sold: 1980 IH Scout Traveler- Nissan SD33T Diesel

Do you think injecting hot water in the pre-turbo exhaust help reduce turbo lap? Water has a 1600 to 1 expansion rate when change from a liquid to a gas.

No. The energy to convert a liquid to a gas has to come from somewhere. By taking heat from the exhaust it is cooled. Cooling the exhaust reduces its volume and slows its velocity.

FI, are you still using your alcohol pump? If not, I'll buy it off you.

I'm going to go ahead and try this modification out anyways(pending paycheck), but I'll probably end up injecting much more alcohol than the 300cc/min

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$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

I'm not using it right now but I have plans for it.

Read these threads.
http://www.***************/forum/showthread.php?t=475
http://www.***************/forum/showthread.php?t=159

What plans do you have FI? Coz I can't understand it from the links you posted. I read only that Dave didn't get any decrease in egts.

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1992 Mercedes 190D 2.5 turbo 5sp manual. EGT+boost gauges. Boost controller set to ~14.5 psi. 1 1/4 turns on full load adjustment. LPG injection. Next in the list is water injection.

Port injection.

What's the advantage? Better atomization with smaller injectors? Also, wouldn't the water have more time to evaporate if injected right after the turbo rather than at the intake manifold?

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1992 Mercedes 190D 2.5 turbo 5sp manual. EGT+boost gauges. Boost controller set to ~14.5 psi. 1 1/4 turns on full load adjustment. LPG injection. Next in the list is water injection.

Yes. Better atomization and even distribution.

It would, but like water sprayed on a hot plate it will still evaporate very quickly.

FI have you decided what injector size to use? Buying 5 injectors and finding out they're not the size you want is not a good thing.

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1992 Mercedes 190D 2.5 turbo 5sp manual. EGT+boost gauges. Boost controller set to ~14.5 psi. 1 1/4 turns on full load adjustment. LPG injection. Next in the list is water injection.

Its going to be quite a while before I do it so I haven't settled on the exact sizes yet. I want 500-600cc/min total volume at 110psi in two stages, one for cruise and one for power.

First stage will be a single ~100cc/min injector at the manifold inlet that will be on when the throttle linkage above idle (with an oil pressure safety switch to prevent flooding). I'll use an accumulator inline to reduce pump cycling. The first stage is to help keep the engine clean of carbon and get a touch MPG boost.

Second stage will be five ~85cc/min port injectors triggered at ~10psi.