[Stucker21trt]

I was talking with an acquaintance the other day and he mentioned lean-out, which he claimed "all the racers" were doing. His original remark was in regards to R/C engines, but said it applied to larger engines as well. Now, for an aircooled R/C engine this might make sense, seeing as how they probably tune the mixture rich, using the excess fuel for its cooling properties. As fuel runs out, the mixture leans toward the optimum for power, the engine gives one last burst of power before shutting down. I can't say that the same thing jives with the larger engines, because I have often seen best power A/F ratios of ~12.5-13.8. Even if this phenomenon does work, it would seem like a good way to frag motors.

Any confirmation as to the truth of this lean-out idea in R/C engines? In case it wasn't obvious I know -nothing- about them. Please proceed with telling me why lean-out is completely stupid for an automotive application.

-Steve

[blown5.0]

well I cant speculate too much on r/c engines.

but as for as cars go, lean is fast. a/f ratio's around 14-14.5:1 are were the max power is. on mild n/a cars you cant get away with this without damage. but on a nos, blown or turbo car with big hp you will burn a piston in no time. I dyno'd my ride when I got the new motor combo done and it like 14:1 where it made max power, and I decide to up jet to get 13.5:1 were it only lost 3 or 4 hp but made it alot safer for long term.