What cruise settings do you use most often?
 

Fellow Pilots,
I am interested in what other pilots are using for their cruise settings and associated performance with their selected setting.
I have an RV-7A with a FADEC controlled IOF-360 and where possible I elect to use the following settings::)

RPM-2350
MAP-21.5"
TAS-160kts
FF-29.5L/hr
DA-8500
Indicated HP - 65%

I can fully open the throttle and or increase RPM to fly into the mid 175KTAS though fuel burn correspondingly increases as well as noise levels hence I elect to cruise comfortably at the above settings.

Interested in your experiences.

Cheers, Greg

My sweet spot
 

21" square LOP

Steve

Settings
 

I generally run 23 squared till I'm above whatever altitude the manifold starts to drop, then it's full throttle, 2300rpm, LOP burning about 6.5 gph with about 165kts TAS. If I want to burn more gas, I push the fuel flow up to just short of 10gph and true out 173kts. IO-360 angle valve RV-8 with Robert Paisley's EFII dual electronic ignition.

That ignition system sure helps get the LOP fuel flow down. Saving 3gph by slowing down 10-12 kts is sure worth it!

No this is not a paid advertisement!:D

OPTIMUM


Wide Open Throttle ALL the time except when in the yellow arc on descent or on downwind and landing. This is the maximum efficiency for the engine.

anywhere around 2400-2500 wherever it is smoothest. (2000-2100 on descent)

Ranging from 60-80dF LOP at high powers (approx 80%) down to 10-20dF LOP at higher levels below 65%. If in the flight levels and I want more power I will run 75+dF ROP, but that is not efficient.

Greg, check your PM's, I see you are down in Sale, Victoria. ;)

24,5 mp
2450 rpm
10,7 gal/hr
170 TaS
370 egt
1340 cht
187 oil temp
22,4 psi fuel pump
Smooth

cruising up high


race prep....this was 13gph 2600rpm. sorry the pic is chopped off. It's tough to take a no-glare pic while running flat out looking for birds.


A lot of my flying is between 8500-12500. I flight plan for 175kts 9gph and always do better than that.

b

High and fast.
 

In my -10...23", 2375, 15.5 GPH, ROP and 175 Knots at 7,500'.

Yeah, it's a high fuel burn but the airplane was bought with the intention of running in the 200 MPH range OFTEN:)

Best,

old school 6A, mags o-360 FP sensi 85", 150KTS, 8 gal/hr ROP car gas/100ll mix. :)

Most 4 bangers run best (smoothest) around 2400 RPM (+/- 50).

Normally for cruise if I'm trying to get somewhere I run:
2400 RPM
22"
10-20 deg. LOP which yields around 7.5 GPH @ 165K Avg.

Just puttin around town I will run the same RPM at 19-20" with lower fuel flows (6.5 GPH). Lower power settings = greater TBO :D

Higher is better, especially with the F1 EVO wing. My power settings at cruise are in the 55 to 65% range. I run at best power, 50 ROP. LOP works, I burn less fuel per hour, but I also lose about 10 knots.
On a three hour flight like this, LOP would have saved me 1.4 gallons and added about 10 minutes to the flight. That 10 minutes does not sound like much but it comes right off my TBO. I know that experimental do not have a regular TBO but they DO eventually wear out and extra engine hours ARE extra engine hours. This expense needs to be considered when calculating the true savings while running LOP. Besides, if I wanted to go slow I would have a different airplane!

Typically at 5000' I file 200 knots, 12 gallons
at 10,000' I file 210 knots 11.5 gallons
at 13,000' see below! 218 knots TAS, 10.6 gallons per hour.

At lower altitudes I will run a higher MP then RPM, say 23" and 2200 rpm, up high I do not have that choice and 2300 seems like a nice smooth number.