Bill, you're running a Catto prop, right? Seeing those numbers, I'm thinking that I must be leaving power on the table somewhere. I was at 7500 yesterday, DA around 8k, and getting 145kt TAS on 7(!) GPH. Catto 3-blade, repitched once to increase RPM. Hmm.
Yes, I have a Catto but mine is a two bladed that I asked Craig to cut as an "Uber Cruiser". It still climbs like crazy, solo I can see a bit over 2,000 FPM, if I want to. (That's solo, not at GW.)
Catto said I'm probably "closer to 200 HP than 180 HP based on how fast I can turn my prop. At 8,000' DA I can see 175 knots (200 mph) but at 2830 RPM, not where I really want to run it.
One other thing, I am a taildragger. Your nose wheel may impact your speed a bit more than expected.
Same. My normal cruise at 8k and 60% power is a bit shy of 7GPM, 142ish KTAS. That's with 150HP and a sensenich fixed pitch metal prop.
Chris
Remember, I have an O-360 that ECi rated at 188 HP, so my percent power numbers will be different than yours.
Chris, I have dual P-mags which allow me to run well LOP, even with my carb. That 25% percent power blew me away.
Over the weekend I was doing some formation flights with my neighbor in his Champ. I was at 15%, ROP, to go 80 knots. I was way rich trying to keep my CHT's cool at those low airspeeds. As soon as he would climb, my airspeed would drop below 60 knots and I would put in 10 degrees of flaps to stay with him in the climb. When he would level out, I would retract the flaps again. It was a fun dance.