Water/meth injection does a wonderful job of bumping octane and allowing you to run more boost and or timing as we all know. Even just water injection does the same job to a lesser extent.

I'm thinking since my civic is my daily driver and tends to see a lot of miles and gas consumption why not drop from 91 (premium in KC) to 87 with water injection. Its 25 cents a gallon cheaper for 87 and when I do stomp on it the water injection should allow me to run it hard in boost. I'm only playing in the 10 to 15 lb boost range anyways. Pretty small time compare to a lot of you guys race builds.

Anyone doing this already? Seems like a win win unless there's something I'm missing.
I have a J&S Vampire anti-knock so I'd keep an eye on things there while tuning.

 

sounds like a waste of time to save 3 dollars per tank of gas.

 

Depends on how much a cheap water injection setup will cost. If I can get one installed for a reasonable price on a DD it'll pay for itself and then some.

 

and if it fails for some reason? cost savings gone, and then some.

 

If it fails the motor will attempt to knock but the J&S Vampire will immediately pull timing and save the motor. If you're not familiar with those units they work very well. Been running my mustang at 20 lbs of boost on 91 pump gas with water/meth injection for a long time. Also with a J&S Vampire which has saved my motor a few times when water/meth ran out. It pulls 1/2 degree of timing per crank revolution on the specific cylinder that's knocking till it stops knocking. Up to 20 degrees of timing can be pulled. I've tested it out (granted by accident) on both the mustang and civic quite a few times while tuning and playing around. Works very well.

 

I agree. Remember its the combination of your 91+ octane and the meth/water that helps so much. Not worth the $3 per tank when detonation could be an issue, even if you change the mix from 50/50 to a ratio that's higher.

J&S should be a supplement to making sure that there is longevity, not to increase your need to rely on it as a sole safety net. Is that worth $3 a tank... I wouldn't think so.