According to a report in AvWeb, Continental is now on the record for being in favor of 94UL as the new avgas. This would mean all airplanes with IO-550’s, like the SR-22 delivered yesterday, would need to have significant rework done, probably some combination of lower compression pistons and timing changes, in order to reduce the octane needs. Yes, you would take a performance hit, they just won’t have the current horsepower available with 100LL. It’s OK, not only will Continental sell the parts needed to do this, but they’ve also announced a new line of diesel engines (technology licensed from SMA) that might have 300HP engines in just a few years.
If TCM’s 94UL consortium prevails, lucky folk like me, with a 285HP IO-520 in an older Bonanza, will probably have to buy a new crank, pistons and cylinders in order to convert my 285HP 520 into a detuned 285HP IO-550 remarkably like the detuned 550 the SR22 crowd will be running. The good news is that SR22’s will no longer be able to outrun me…
This is serious stuff. Something like 75% of avgas is burned by those of us running IO-470N, IO-520 and IO-550’s, not to mention the higher compression Lycomings of which I’m too ignorant to list. TCM is apparently trying to throw us under the bus, despite there being at least two serious proposals for 100 octane unleaded replacement fuels on the table.
http://www.avweb.com/eletter/archives/avflash/1629-full.html
Lycoming is apparently not on the 94UL bandwagon.