I understand that you = like to go fast, and believe me, I explored also all ROP/LOP with temps = etc. But the best answer to your question is: 70% power ROP =3D 70% = power LOP, or in other words, when you are running your engine at 70% = power it doesn't matter if you are running LOP or ROP = !

70% power of 350hp =3D 245hp and if you do this = running LOP or ROP it stays the same hp and therefore (in theory) your = plane should fly the same speed (this I gathered at the last Lancair = meeting from Tim Roehl, GAMI over lunch, really good = stuff)

So....now the question stays, how much = fuel flow do I need to get 70%hp from a 350hp engine, because that is = what is moving your plane forward. (you can google the numbers but if I = remember correctly ~18.5gph/2500rpm/32map but don't take my word for it, = you just have to make sure you are at least 70 degrees LOP to run it = that high, at lower MAP you can go even back to 25 degrees = LOP)

Just keep in mind that running your engine = at 70%hp is really the same LOP or ROP (now I know that perhaps your = engine monitor says that you are at 70% but they also have their error = margin, best thing to do is to calculate it = through).

I hope this helps.....it did with me = :)~ And who doesn't want to save money if the plane is flying the same = speed LOP :)~

-- Ronald (110hours LNC4, = 360hours Velocity TXL5, 1100hours Cirrus sr22 and = some....)

ps I also asked Tim using TIT as tool = and he confirmed that TIT is the average temp from your cylinders, but = important here is that the GAMI spread should be very small (like < = 0.5 gph) otherwise you could run into troubles without knowing = this.

On Dec 6, 2011, at 3:23 PM, <bronnenmeier@GROBSYSTEMS.COM<= /a>> <bronnenmeier@GROBSYSTEMS.COM<= /a>> wrote:

Dear = subscribers,

When I run the engine lean of peak with a turbo temp = around 1650 degree (75 LOP) I get really nice results in regards to head = temp and IAS.

Studying the articles I understand that coming from the = lean side first the TIT peaks and then head temps will peak later (means = richer).

In case I really want to go fast sometime and don=92t care = about fuel consumption:

Can anyone give me a temp spread that I need to stay on = the rich side from the peak TIT in order to be on the declining rich = side of the head temp line and be safe?

Or is there another procedure = to run ROP and have nice cool head temps. The fuel flow settings in the = Continental for ROP operation make my head temps slowly creep above = 400.

Thanks for your = help