hello Rob! thanks for your input about turbojets.....in fact the thrust is increased on a turbojet engine with water injection because that water has to go somewhere and it goes thrue the turbine in the form of steam and oxygen...you know that water is oxygen and nitrogen....it separates here by the heat and it also allowes more fuel to be injected , more total mass flow thrue the turbine means increased thrust on a turbojet engine...the US air force used this method on the Boeing B52 stratofortress bomber and on the boeing KC 135 stratotanker to increase the thrust during liftoff from the runway. i will use the water/methanol injection at power levels above 3/4 of the throttle....the methanol adding is used to restore the turbine housing and turbine temps so it dont get thermal shock because the methanol will burn inside the engine, enough methanol will be added so the turbine temps be equal to the temps without water/methanol injection....it takes a lot of testing to get there but it can be done. bearings survive qite good on such an engine, this hobby is a very big hobby in the US and in the UK...i know one guy which has run his engine for over 300 hours....it is a matter of proper tuning, oil supply with the correct oil press (which must be higher than the compressor disharge pressure to avoid the compressor from pulling the turbine shaft against the thrust bearing,destroying it)and with good oil cooling and proper engine monitoring such as all the pressures,oil press and fuel press,the P2(compressor discharge pressure) the P4(jet pipe pressure)and the compressor discharge temp and ofcourse TIT(turbine inlet temp)and TOT(turbine outlet temp) and reading of the RPMs ofcourse to avoid overrevving of the engine(it also helps a great deal in tuning such an engine to read the RPMs when an event is happening at what RPM)and reading of the ambient temps as well is a good help, do all that monitoring then the engine survive.....i have read tons of info on this matter....thanks for your guesstimating of turbine housings, it was to great help in calculating stuff for the engine.......thanks Rob......best regards/stephan