Why is LOP (lean of peak) controversial?

"Peter R." wrote:

In my case, my engine's cylinder head temperatures rarely get above 310
degrees F and most times operate in the 285 degree F range during cruise
flight. The times they do climb to 310 or 320 degrees F is when I am
climbing to altitude on a very hot day.

I should have included that 380 degrees F is considered the absolute top
end of the safe temperature curve, at least according to Tornado Alley
Turbo and GAMI, both of whom have done extensive testing of LOP operations.

Even on a hot day at higher density altitude (and effectively less ram air
cooling), 320 degrees F is the highest I have seen my cylinder head
temperatures reach.

--
Peter

"Peter R." wrote in message
...
"Peter R." wrote:

In my case, my engine's cylinder head temperatures rarely get above 310
degrees F and most times operate in the 285 degree F range during cruise
flight. The times they do climb to 310 or 320 degrees F is when I am
climbing to altitude on a very hot day.

I should have included that 380 degrees F is considered the absolute top
end of the safe temperature curve, at least according to Tornado Alley
Turbo and GAMI, both of whom have done extensive testing of LOP
operations.

Even on a hot day at higher density altitude (and effectively less ram air
cooling), 320 degrees F is the highest I have seen my cylinder head
temperatures reach.

What % of power are you using? I'm usually around 360-370, but I'm running
70-75%.

Matt Barrow wrote:

What % of power are you using? I'm usually around 360-370, but I'm running
70-75%.

I also cruise around 75% of the IO-520's 285 hp.

--
Peter

"Peter R." wrote in message
...
Matt Barrow wrote:

What % of power are you using? I'm usually around 360-370, but I'm
running
70-75%.

I also cruise around 75% of the IO-520's 285 hp.

What altitude? FF?

Matt Barrow wrote:

"Peter R." wrote in message
...
Matt Barrow wrote:

What % of power are you using? I'm usually around 360-370, but I'm
running
70-75%.

I also cruise around 75% of the IO-520's 285 hp.

What altitude? FF?

In summer temperatures at 12,000-15,000 feet I get about 187-190 kts TAS at
about 15 gph. In the winter, I see 175-180 kts TAS and 16.5 gph or so.

--
Peter

Peter R. wrote:
Matt Barrow wrote:

"Peter R." wrote in message
...
Matt Barrow wrote:

What % of power are you using? I'm usually around 360-370, but I'm
running
70-75%.

I also cruise around 75% of the IO-520's 285 hp.

What altitude? FF?

In summer temperatures at 12,000-15,000 feet I get about 187-190 kts TAS at
about 15 gph. In the winter, I see 175-180 kts TAS and 16.5 gph or so.

--
Peter

Unless the LOP "formulas" have changed (which IS entirely possible,
been a few years since I had to think/worry about it) anything much
over 14.5 GPH would be considered higher than 75% power.

285 HP x .75 = 213.75 HP / 14.9 HP/G = approx 14.3 GPH @ 75% operating
LOP

If your CHT's are closer to 300 F than 400 F running those settings,
you've got one of the "cooler" installations that I've ever heard of...

TC

" wrote:

If your CHT's are closer to 300 F than 400 F running those settings,
you've got one of the "cooler" installations that I've ever heard of...

The cylinders are new Superior Millennium cylinders with about 250 hours on
them, if that has anything to do with the cooler temperatures.

And yes, my engine's CHTs are normally below or around 300 and have never
approached 400, routinely. If you would like some verification of this, I
would be happy to upload my engine monitor data (from several months ago, I
have yet to download a current set), which is in the latest JPI format, to
a free host site for anyone's perusal.

--
Peter