jet placement: why not cool combustion, not the manifold????

[keithmac]

The closer you place the nozzles to the valves the better the knock limiting effects but it lessens the charge cooling effect. Since you don`t need to cool the charge you don`t need a long run for the water to mix/ evapourate and cool the air. If you`re using wi soley for knock limiting you need to get as close to the inlets as possible, near port injection may be the best way to go for your setup?, also make sure each cylinder is getting the same amount of spray (ideally 1 jet per cylinder).