[sambeeb]

Despite the issues i've raised, excessive IAT's were the primary reason that I fitted the post IC WI in the first place. I didn't want to run meth from there though worried that it could affect the throttle body circuitry. In high ambient temps with water alone I did succeed in dropping IAT's from 50 to 40 degrees as measured across the short 10 inch distance from the IC outlet to the throttle body temp sensor. I understand now why I am not able to get rid of timing pull though. The plenum had always felt cold to the touch and I'd assumed from that that plenty of water in droplet form would have been getting into the cylinders, but now I see this was more than likely due to wet down walls than anything else.

"if you are hampered by a low efficiency of your (too small) turbo, consider pre turbo injection.
if you are hampered with poor charge cooling and excessive IATs despite a efficient turbo, consider post IC injection"

Since my turbo is basically INefficient at the degree to which its being pushed and post IC water injection is not having the desired anti knock effect, maybe the best thing will be pre compressor injection then. I had looked long and hard at boost pressurised systems and liked their simplicity and the fact that in a purely mechanical system you could achieve flow somewhat proportional to boost.
Can I ask a question on that topic then - it would be a system that I'd only use at hillclimbs so the IC would have to remain in place for when its street driven. Would the presence of the IC have an bearing on whether or not I run water alone or water/meth? Yes the IC is small side mount (similar to the golf mk4 setup) but it is always kept cool with a water spray, IC fan and good ducting and runs are less than 1 minute.

thanks
sam