water injection
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
As I recall, water injection was used to keep high compression engines from having preignition problems (pinging, detonation...the serious kind) on aircraft piston engines. It caused the combustion process to slow down a bit and yielded some added efficiency under certain conditions.
I don't think your '80s C3 engine with 8.5:1 compression would see any benefit from water injection. But, the purchase of such a system for your car would help 'inject' some needed cash into the economy. Go for it!
I don't think your '80s C3 engine with 8.5:1 compression would see any benefit from water injection. But, the purchase of such a system for your car would help 'inject' some needed cash into the economy. Go for it!
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
It works great on boosted applications. With the turbo eclipse I had it would start knocking at 15psi. I installed an injection system and ran a water/methanol tank. It was set to come on at 15psi of boost. Datalogging showed intake and exhaust temps dropped dramatically. It allowed me to go all the way to 20 psi of boost before it started showing preignition on the logger. On a bone stock low compression 350 the intake charge may not get hot enough to totally vaporize the water but if it did it would allow you to advance the timing more adding a few more horses.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
No good for a driver car and very little benefit for most racing...but I have read somewhere that some WWII aircraft used water to lean a engine down to go faster in a so called War emergency situation....
Le Mans Master
Joined: Oct 2006
Posts: 8,941
Likes: 35
From: El Cajon California
I had a Spearco unit 25+ years go with a Pontiac 455 shortblock and heads off a Pontiac 421. I don't recall the compression, but it was high water injection kept the motor running strong with regular gas and some advance. I miss that car.
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,634
Likes: 1
From: aurora
It works great on boosted applications. With the turbo eclipse I had it would start knocking at 15psi. I installed an injection system and ran a water/methanol tank. It was set to come on at 15psi of boost. Datalogging showed intake and exhaust temps dropped dramatically. It allowed me to go all the way to 20 psi of boost before it started showing preignition on the logger. On a bone stock low compression 350 the intake charge may not get hot enough to totally vaporize the water but if it did it would allow you to advance the timing more adding a few more horses.
thanks
Drifting
Joined: Nov 2000
Posts: 1,390
Likes: 39
From: North Brunswick NJ
Olds offered a water injection system in the early 60's on their small 215 ci aluminum blown motor. It wasnt to popular as it only lasted a year or two. I believe it was a special F-85 model.
Ed
Ed
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Drifting
Joined: Sep 2006
Posts: 1,986
Likes: 21
From: Columbus MN
The P51 Mustang had a water injection switch on the throttle for "emergency" use during dogfights to allow overboosting. Pilots were supposed to use it sparingly because it overstressed the engine.
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 315
2024 C3 of the Year Finalist - Unmodified
My dad used to fly "the hump" over the Himalayas. According to him, it was an ethylene glycol mixture whose purpose was to allow running the leanest air/fuel mixture possible without raising cylinder head temperatures. I suppose this was done to conserve fuel and extend range. The C-47B used in the China-India-Burma theater was supercharged to get over the mountains. It wasn't pressurized, but they did fly high (26,000 ft service ceiling) and in the cold.
Last edited by Faster Rat; Jun 1, 2010 at 01:39 PM.
Racer
Joined: Aug 2006
Posts: 330
Likes: 3
From: Wellington, New Zealand
Allison V1710 aircraft engines used a 50/50 mix of methanol and water to cool the manifolds and stop detonation. Superchargers beat the air to death as it passes through them and this causes the temperature to increase. I don't really see any benefit from water injection on a street car, but it does reduce carbon buildup on valves and in the combustion chamber. A engine thats burning a bit of oil tends to run better and cleaner with water injection.
