Bob,
>
> Generally the Manifold pressure was maintained to 27 inches excepting
> a timed 1000ft/2000ft 100% power climb at 85kts
>
> 80seconds.. one hour later (fuel used lighter) 1,500ft/2500ft..115%
> power climb at 80kts.60seconds .I failed to collect the manifold
> pressures during the climbs. However the intake manifold locally
> insulated surface temperature was 31.1deg C during the initial climb
> and 35 deg C during the high power climb. 100- 110kt cruise 5,150 RPM
> the intake manifold temp at 2000ft was 27.4 deg C. (but in this
> instance the manifold pressure was 29)
>
Our usual settings are as follows :
39"/5800 => 115 % for take off
35"/5500 => 100 % initial climb
31"/5000 => 75 % for cruise & climb
29"/4800 => 65 % for economical cruise
28"/4300 => 55 % (very rarely used)
I don't know the output for 5150 RPM.
27" seems rather low for break in : you need manifold pressure for the
rings to bed in.
> Intake manifold temp. at 1000ft 70kts was 30.8 deg C . At 100kt cruise
> the coolant temperature was 92 deg C . Oil temperature was 98 deg C
> with oil pressure at 2 bar.
>
> I am using Mobil One 0w -40w and find myself wanting to increase the
> oil pressure somewhat although the light viscosity oil must be
> reaching places where more viscous oils dont reach ! Would anyone
> care to pass comment on the suitability of a higher oil pressure and
> the generally accepted best climb speed, please?
>
> The engine does not now appear to be using/loosing oil from engine/turbo.
>
> The rising coolant temps. on the sustained 115% climb would not have
> enabled a 5 minute climb.
>
Our cooling setup allows for close to 5 minutes 115 % climb, but we
never bothered to wait until the 5 minute light flashes.
I usually reduce power to 100 % as soon as I'm airborne.
>
> Would any capable statistician care to crunch/nit pick these figures
> ? and make appropriate recommendations with regards to the oil
> pressure ? and does anyone have any comparable intake manifold locally
> insulated surface temps without an intercooler fitted?
>
Unfortunately, we did not make those measurements, and our engine is
intercooled. We focused on airbox temperatures.
Yes the 914 oil pressure seems lowish, but it is the way the engine works.
Remember the oil pressure is usually measured at the oil pump, but we
have no means to know what the pressure actually is at the journals,
etc...Certainly much lower than the healthy number usually displayed by
the gauge on other engines.
Sooo, as long as the pressure stays within the manufacturer's numbers...
Best regards,
--
Gilles
http://contrails.free.fr
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