ok mabey this isnt a new idea, but i keep thinking about how transfering the exhaust(some of it) back into the intake might help reduce detonation(pre-ignition) and eliminate the need to retard the timeing. ive heard of water injection systems for RV's and such for climbing hills or for hauling something heavy to help reduce detonation. im thinking about an engine running off pure hho, since the exhaust would be water vapour. if someone has already suggested this or there was some big discussion on it months ago than just ignore me....