rpm limit on Sensenich prop for O-320?

[vlittle]

Originally Posted by az_gila

Actually, it's 157 HP at 2600 rpm per the Lycoming O-320 Operator's Manual... (98.1%)

gil in Tucson ... who likes real numbers...

Actually, Lycoming has different numbers for different O-320 models. The -B amd -D series show about 159.5 HP at 2600 RPM, sea level power. I think Superior's data is similar.

Lycoming's D2J model shows 155 HP at 2600 RPM.

Finally, the reality of the typical RV installation, is that you'll a bit of MAP boost due to ram air affects on the intake. My calibration data shows that this gives about 3-4 HP.

Bottom line? You may actually be seeing more than rated HP.

[az_gila]

Originally Posted by vlittle

Actually, Lycoming has different numbers for different O-320 models. The -B amd -D series show about 159.5 HP at 2600 RPM, sea level power. I think Superior's data is similar.

Lycoming's D2J model shows 155 HP at 2600 RPM.

Finally, the reality of the typical RV installation, is that you'll a bit of MAP boost due to ram air affects on the intake. My calibration data shows that this gives about 3-4 HP.

Bottom line? You may actually be seeing more than rated HP.

OK Vern.... now I'm confused....

My O-320 Lycoming Operators Manual has two applicable figures for 160 HP versions.
Both are titled Sea Level Power....

Fig 3-5 "Sea Level Power Curve - O-320-B and -D series"
and
Fig 3-14 "Sea Level Power - O-320-D1D"

The first one is t 157 HP I quoted, the second one shows about 155 HP @ 2600 rpm, and is a version with a horizontal HA-6 carb.

The pages have a revision date of Jan, 1977.

Am I looking at the curves wrong? are these the correct curves? or do I have old data?

The two curves quoted above have 160 HP at 2700 rpm as a marked point (makes sense... ...)

gil in Tucson - more inconsistent Lycoming data?