Fuel consumption/Relief tubes and related

[SkyKing]

Dear "cbrsrceo"...

Here are the numbers for a 1977 P337 with 148 gal fuel:

Max speed @ FL200: 217 Knots
Cruise, 75% power at FL200: 205 Knots
Cruise, 75% power at 10,000 feet: 186 Knots

Max Range at FL200 with 888 pounds usable fuel: 1,155nm/7hrs
Max Range at 10,000 feet, ditto on fuel: 1,110nm/7.3hrs

Nominal Range @ 75% power at FL200: 985nm/5hrs

The nice thing with turbos, rate of climb is still 870 FPM at FL200 at full gross, and you'll always be climbing faster that the 337G counterpart.

Best of all, at FL200, your cabin altitude will be around 10,000. If everything is in proper operating order, the P337 should maintain a sea-level cabin up to 7,000 feet, and in between at say 14,000 feet your cabin will be down at 5,500 feet. There is also a distinctive quieting effect of pressurization.

The above figures are from the POH.

BTW, you'll want to be aware that most of the early P337's, say 1973 vintage, still had (or have) the TSIO-360C engines and a number of those had a potential problem of cracked cases, mainly on the rear engine position. The CB6 version seemed to cure that TCM 'defect'. Of course, this won't be a problem unless the plane has the original engines SNEW.

SkyKing