i can report that wi does help in piston cooling as i have proven this down at courtenays on there rollers(ask jon) i have a jet in the throttle body and i am using a 75/25 meth/wat mix,we did a run without wi on and the ecu cut the timing due to the heat soak but with wi on the ecu did not cut the timing at all so it does help keep temp down so in a way it is a gain in safety and peace of mind that ur engine is running more cooler so there is less chance of pinking at higher rpm.
. i am running two s1 kits one for piston cooling and one for charged air cooling(switch off at mo as dont need it up here in a very cold aberdeen lol) i also have a custom made water tank for the charged air cooling only,
