I had a school buddy (1985-86) that had a 70's muscle car. To save money on gas he used water injection so he could run regular gas instead of premium. He claimed the water in the intake charge elimiated the pinging but he also ran a little less advance. I think there was a company selling the water injector kits for a while in the 80's?
it sounds like everyone is NOT on the same sheet of music.
"asinn" do you really know what water injection systems are?
besides, its just like saying getting a intercooler for a manifold mounted supercharger. the air will be cool going in, but the minute it hits the vacuum and the intake manifold, the temp will be right back up. maybe not as hot, but its definitely not worth it.