(This question applies equally well to the IO-360, which there's a lot more information and history about.)
I notice that, while the standard IO-360s (both parallel and angle valve) spin at 2700 rpm max, the HIO-360 variants start at 2900 rpm and go right up to 3200 rpm. Am I right in assuming that there's no deep difference between these engines that permits this overspeed, just different overhaul times and comfort levels? Could one further extrapolate to say that spinning a well maintained IO-360 at 3200 rpm with sufficient cooling is likely (obviously, no guarantees) to be substantially safe for roughly the HIO-360 TBO? And, finally, is there enough torque available above 2700 rpm for this to give, if not 20% more power, at least a noticeable chunk?
Any reason this would be different on an IO-390?
I notice that, while the standard IO-360s (both parallel and angle valve) spin at 2700 rpm max, the HIO-360 variants start at 2900 rpm and go right up to 3200 rpm. Am I right in assuming that there's no deep difference between these engines that permits this overspeed, just different overhaul times and comfort levels? Could one further extrapolate to say that spinning a well maintained IO-360 at 3200 rpm with sufficient cooling is likely (obviously, no guarantees) to be substantially safe for roughly the HIO-360 TBO? And, finally, is there enough torque available above 2700 rpm for this to give, if not 20% more power, at least a noticeable chunk?
Any reason this would be different on an IO-390?
