XP-360 run sheet from Superior

[whifof100ll]

Just got my XP-360 from Superior. It is a vertical induction engine with standard pistons (8.5:1) Precision Airhawk FI, one slick mag, and 1 LS plasma II plus. I did not do the builder program, so I really don't have a grasp of their engine run test apparatus.

I found the run sheet a bit confusing. They told me that they load the engine with a known fixed prop, and estimate horsepower with a calculation that considers RPM, wind, inducion temp ect. I'm sure their power output estimates are specific to their test run stand. From the description I got from them, they hit a button where a snapshot of test stand parameters are logged and then power is estimated for the engine adjusted to sea level and standard temperature and wind velocity at the stand. They allow +- 3% from expected. The numbers seem a bit funny in that BHPc and BHPcn are so different. I would imagine that BHPc is the measured power output as BHPcn is the corrected power output. I did not get this directly from who I spoke to at Superior about it, but it is just my best guess. If anybody has a good understanding, I would appreciate the education.

In the end, I guess that the important thing is to know that the engine puts out similar numbers to a properly built engine.

My numbers for the only WOT data point taken are below. I would appreciate comparison with other XP-360 run sheet recipients.


Intake air temp = 91 deg F.
Baro press = 29.37" Hg
RPM = 2649
Manifold Pressure = 28.71 "Hg
Oil Press = 81 PSIG
Oil Temp = 158 deg F.
CHT/EGT 1 = 356/1351
CHT/EGT 2 = 343/1338
CHT/EGT 3 = 372/1359
CHT/EGT 4 = 379/1366
BHPc = 155.82
BSFC = 0.6564 Lb/Hp Sec

In the comments section they write
Acceptance test
BHPcn = 182.9 HP
BSFCn = 0.6040