turbo and WATer injector

Jukka Majanen jiipm at sci.fi
Mon Aug 28 10:53:17 EDT 2000


Yep Sam! And how about UK-made Napier Marine engines with 
water injection? Specially that huge Napier Deltic not Vee, but in
delta form? Ok that`s past ;-)

Main reasons for water injection were ( are ) mostly: pressurised 
intake air cooling and in gas engines to prevent the knocking and 
in the diesels ( big ones ) cleaning also the charger.

At `80s we tested an otto engine  (2.0 8v with 7.2 compression, 0.7 bar
pressure -stock) giving 145 HP at 5000 rpm. The best results were some 
200hp with 1.35bar and water injected. 50% of alcohol and 50% of water
switched on at 0.8 bar, 0.15 liters a minute. No intercoolers and terrible turbo
lag. Water was injected in before the turbo. That 50% of alcohol had two
functions: It could absorb heat better than water and had energy like gas.
( half part of that the gas includes )

Nowadays there are good charge air ( inter or after :) coolers, knock sensors...
so water injection could be usable only at extreme conditions.

BTW, Todd:

Also we tried to use that starting valve for cooling and extra fueling at the boost
and found some potential in that idea. We just couldn`t regulate it well enough at
that time (some `83-`84 ). Worked quite well at max boost in the mid rpm area,
but it enriched too much at the top, when the boost started to decrease. 

CIS distributor was 6-cyl type with two lines plugged. Pump delivery (from distributor)
was measured some 1.8l/min.

My best
j-pm `91 cq

>How about injecting water into the manifold instead of fuel. An engineer I
>know has done just this on an old Bedford(Yanks won't know what that is eh
>Phil etc)truck.. This allows him to lean waaaay down and cruise just fine,
>similar things were done in the war too I believe
>Sam Clarkson 
>1990 200tqw

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