Water Injection for 6L XJ engine?

Like all the other XJs terrible gas mileage

Looking for those who have tried water/alcohol injection and like or dislike it. I believe the claims for increased power and carbon deposit removal, but are the claims for increased fuel mileage bogus or true?

Reply to
Spud
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I am wondering what engine and vehicle you are talking about. My XJ gets about 26+ US mpg running fully loaded at 75 mph...... I feel this is good mileage and it is an old beastie with over 300K km on it.

Alcohol has way less BTU's per volume and when any mix is used in my CJ7 it cuts the gas mileage instantly by 30% and some mixes go 50% less. My CJ7 gets 23 US mpg with real gasoline.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Spud wrote:

Reply to
Mike Romain

Reply to
L.W.( ßill ) Hughes III

Reply to
L.W.( ßill ) Hughes III

Spud did pass the time by typing:

Never tried.

Water injection has been around for a looooooong time. Increased humidity increases octane and allows for higher comression. While water injection on a supercharged or turbocharged vehicle may be worthwhile I doubt it will help much for a day-to-day driver unless you plan on using a lower octane fuel and offsetting that with water injection.

Water injection systems are not cheap. Good ones run well over 300$.

Long term effects of water injection done properly should be minimal as it's not much different than driving in the rain.

Reply to
DougW

Reply to
Will Honea

There's nothing wrong with the colourtune - it simply lets you find out that the design of your intake manifold is crap ; the cylinders at the end burn a bit lean and the ones in the middle burn a bit rich (on a single carb engine). Can be quite useful for setting up multi-carb engines though.

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Reply to
Dave Milne

Early commercial jets used water injection for take off, it was used in hot climates.

Snow...

Reply to
Snow

Mike: My stock 78 Chevy 4x4 3/4 ton retired farm truck gets @ 10 mpg, I don't consider that too bad for a old clunker with full time 4WD. it's been a superbly reliable vehicle. My wife's 93 Olds Cutlass Cierra gets @ 36 mpg. poorly designed front brake calipers. Our 73 Tioga Motorhome gets about 10 mpg. not bad for the amount of air it pushes. The stock XJ only gets @ 20 mpg., and it's smaller than the Olds.

I have had a Colourtune for 30 years, use it often, bought it new on holidays in UK for $15.00cdn. Great for outboards and motorcycles, 'Never seen anybody else use one.

Bill: "Real Gas", remember it well, we had 7 gas tractors on the farm, I haven't smelt that for years, yup better mileage than the swampgas/propanized/ oxygenized stuff that seems to be everywhere now and it starts rotting in a months time if you don't add fuel pickler to it.

Spud

Reply to
Spud
20 mpg is low for an XJ..... My CJ7 gets better than that. I do give it new plugs and distributor cap and air filter every 2 years for the emissions test, air filter more often usually.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Spud wrote:

Reply to
Mike Romain
100% Alcohol will require doubling the size of carburator jet size, etc. for approx. four times the flow rate. True that water injection will increase the 'octane number' but you will NEED that water injection since alcohol (volumetrically) burns at about 300 degrees hotter than normal gasoline because alcohol 'carries' its own oxygen. I used to burn methanol in a sprint car; and, can tell you that straight alcohol will not be a 'benign' fuel to use as it will require you to regularly rip down and clean out all the intake/exhaust passages (carbon, etc.). Engine wear will be quite accelerated and you will need to continually 'perfect tune' the engine. The down side with alcohol is that if you have a fire in daylight, you cant see the burning alcohol flames and will only know when something is wrong when the paint starts to bubble and the rubber/plastic stuff starts to 'drip'.

Wow 26 mpg with an XJ !!! Ive busted my tail try> I am wondering what engine and vehicle you are talking about. My XJ

Reply to
Rich Hampel

20MPG is typical to good for an XJ, depending on the details. Mike, I don't know what your special circumstances are, but they give uncommonly good results. Hmm, maybe you have Keebler elves working on your vehicles. B
Reply to
Brian

Isn't all Kalifornia Gas now about that mix? All the brands I've tried smell like it, and all drop mileage by about 10% on the freeway. Maybe I should inject some water.

Never heard of gas/water helping an engine unless the engine is turbo-charged. e.g. the old Oldsmobile engine that had a water injection system, where if I recall, the alcohol was mostly just for antifreeze.

L.W.(ßill) Hughes III proclaimed:

Reply to
Lon

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