It just hit me that the speed difference you are seeing is due to flying ROP on the Columbia. You are correct about the speed difference in that case. A TN22 is always flown LOP in cruise. In fact, the way you fly it is ROP and WOT in the climb and then 2500 RPM and 17GPH for cruise i.e. no lean assist or setting of EGT's. If it isn't hot then you can do a LOP climb on the Cirrus.
nope, it is not. I fly the Columbia LOP in cruise and descent, but not in the climb. It would be possible to do a LOP climb in a Columbia, too, but POH says no... so I stick to that. FL180 is a long way up, too...
Real life figures - SR22 Turbo, FL180, 198kt TAS. Standard lean to target (blue line on FF) FF 17.5 USG/hr. Columbia400, 217kt TAS, 1650F TIT LOP, FF 17.2 USG.
A bit leaner on the Columbia because if the 1650 TIT limit - Cirrus Turbos are more robust, and I think generally the Cirrus has the more robust engine, and I just LOVE how they have simplified engine management...
Both were on close-to ISA days, but not on the same day.
And again - so the Columbia is faster - hey, not everyone wants that fast and 198kt are not that slow, either! For pure speed at low fuel flow the Mooney would be even better...