Phil mentioned running only straight 40W oil in his RG2000 by recommendation. Just for the record I will say this is foolish and potentially catastrophic. Straight weight oils went out of use by all engine manufacturers including aircraft by the mid 1970's. Multi-viscosity oils have been used and continually refined to being better and better since that time. With such a superior oil protection and ability in modern oils it doesn't make sense to use old technology. The temp range of operation for straight weight oils is much more restrictive than a similar weight multi.
Most of us are running some version of an auto engine and so we need to use the products that get the most life out of auto engines in hard or severe use. My humble opinion... Some years ago I read an article in Plane and Pilot where they took a C 182 (I think) and raised the horsepower from 230 hp to some 265. They quoted some history on previous models with lower HP and then went on to test the higher rated engine. They used a good old boy assumption that X HP gave this much speed and raised to 230 gave this increase, so raising HP this much to 265 would yield a constant rate of speed increase. It was a practical exampl of proving the aerodynamic principle that if you double the speed, your drag increases by 4 times. HP alone will not significantly increase speed. Climb speed was increased dramatically. This is due to the fact that climb is a reflection of any HP above what is required for level flight is available for climb. So 35 extra HP means better climb immediately at the same speed. But due to no decrease in drag, only a nominal increase in speed was seen both at cruise and wide open throttle. You can add an RG2000 or O 360 to a VP 2 and it will climb great, but will not gain near as much in cruise speed due to the design does not lend itself to low drag. For us KR drivers look at Trop Petteway's plane on Mark L's site, and compare to anyone else's. He probably does not have much more HP than Larry F, running the same family of engines, as was Marty Roberts. Yet he was defintely faster as Mark L can atest. Colin N96TA
