Brian, I am very impressed with your speed results, and if you have actually achieved far less cooling drag, and gained some speed, and you can verify that, all at the same time as having reasonable and manageable CHT's you have hit a sweet spot.
Despite what your A&P said about too much info, data confirms that CHT's should be kept under 380, and that over 400 you really want to avoid this as much as possible. Remember the limits in the manual are certification limits, not where you should be running to if you want a long healthy engine life.
For the average punter, and I would say you are not, but the average guy is going to struggle. What we see is higher CHT's (less margin on hot and or heavy weight days) and we see no speed gain. In fact it could be said speed loss.
Guys like Dan Horton and yourself and a small group have probably cracked the sweet spot, but the vast majority are going to struggle.
When you say "good but not as good as standard" I don't understand. What is the goal you are trying to achieve. As cool as possible? Fast? Even spread?
What I am saying is that assuming most folk will not get a speed gain, or not significant, they should be focussed on making the cooling system deliver lower temps, ROP running around 350-360 max in the cruise is a good goal. Remember in a climb the aim is to keep them under 380F. When running LOP depending on altitude etc you would expect something like 300-330dF.
The standard baffles done properly achieve this. Anything less effective is obviously sub optimal. Is it going to kill your engine? No, but over the life of it it may make a difference to repairs or total life.
So summing up, unless you make significant gains over the standard baffles you are going backwards. For most people that is what needs careful thought. And the reason I think you should aim for the kinds of cruise numbers I am talking about is margin above left over for hot climbs and MTOW and not going over 380.
Jamie, you are a stirrer boy! Wait until you drop in later this morning, I'll set Dudley onto you
Tony, Ignore what the difference in EGT is, that is not critical, probe placement can do that alone. Your CHT's being within 20dF of each other is pretty good and typical. 350dF in the cruise is good, but only if that is ROP, a 10-20dF LOP cruise should yield a bit less. To make a value judgement more info is required.
% POWER on your EMS
To my knowledge, so far the only EMS that are on the market in the TSO world is the Auracle. I know why too, a former VAF contributor spent a lot of time helping them get their overall EMS package correct. In the experimental world the Dynon does it right, for a 8.5CR engine. I am not sure about the others like AFS and GRT but I suspect they may have either ROP or LOP calcs correct but not both. I would like to know if anyone has proof of it.
In simple mental maths terms to do a % power calculation in flight take USGPH x 15 (14.9 for most engines CR) but 15 is near enough. If you are ROP, then Mass Air Flow is the governing factor so a simple (and its rough but close enough) %age of MP x %age of RPM will do it. For example 25"/29.9 is 83.6% and 2430RPM is 2430/2700 or 90%. Answer is roughly 75% power.
In flight you could say .85 x .9 and you get 76.5%.....so who cares. Near enough
Brian, for your Dynon % power, go to your manual and find this section
E
ngine Type Configuration
W
ithin the GLOBAL menu, press DOWN▼ until you have selected ENGINE TYPE. Press SEL► to toggle between LY/CON, ROTAX, and OTHER.
ENGINE TYPE: LY/CON
Setting ENGINE TYPE to LY/CON enables a percent power display for normally aspirated/non-turbocharged Lycoming or Continental engines. Press DOWN▼ to select HP RATING and use the INC+ and DEC- buttons to set the value to the actual horsepower rating for your engine. Given the horsepower rating, an OAT, fuel flow, and altitude (from a connected EFIS-based product or GPS), the EMS-D120 will calculate percent power and lean-of-peak/rich-of-peak status, displaying both next to the Manifold Pressure gauge.
For percent power status to be calculated as accurately as possible, TACHOMETER (RPM) HI RED/YEL should be set to the RPM value specified by the Engine Manufacturer. (This is commonly referred to as ?Redline?).
I
f you do not have a fuel flow sender, the EMS-D120 will still display a percent power reading based on rich-of-peak calculations only. During lean-of-peak operation, percent power is displayed but is incorrect. While you are in LEAN mode, percent power is not displayed.
I hope that is helpful