11-26-04  .6 hours  /  40.6 total

Took a brief trip up to test the WOT speed at 8000 feet, and to test the new oil cooler scoop, and TB inlet.  The OAT was reading 58 when I went out, so it was almost a “standard” day.  This is the coldest temp that I’ve started the engine, and it certainly acted differently. 

First, it took quite a bit more cranking than normal to fire it off, but that’s too be expected.  Once it starts, I always turn off the cold start switch immediately, but leave the mixture full rich.  Today, this worked fine, until I tried to throttle up to about 3000 to warm up.  There just wasn’t enough fuel to do it.  I left it at about 2200 rpm, which was as high as I could go with the mixture full rich.  As the engine warmed up some, you could see the mixture getting richer, and richer until it was basically back to normal.  Very odd. 

I tried the B controller and it faltered.  Tried turning off the primary injectors, and it wasn’t happy, ignition backfired.  Basically, the engine is just stubborn when cold.  Once it was mostly warmed up, all was back to normal, though I did get a bit of an rpm sag on climb out, which required a bit more mixture to eliminate.  Got my attention though. 

Speaking of warming up, it sure took a long time to get the oil temp over 140.  I was taking this to be a good sign for my oil cooler scoop mod, but that hope was shattered in the air.  Unfortunately, the oil temps are still a problem.  I made it to about 6000 feet before hitting 210, but it continued to climb, so I backed off the throttle and added speed.  During my WOT runs at 8000 feet, the temp eventually climbed to 220.  Rats, gotta do something about this. Let’s see, how many times it Ed say he had to change his oil cooler arrangement until he got it right :-)    Water cooling continues to be more than adequate for any condition, and was only in the 170 range during my WOT runs.   During a long (rapid at times) descent  (I was playing), I noticed the oil at 138, and water was 105.  Gotta keep an eye on that too I guess.  

During climb, I was at 100-110 mph, and I saw sustained VSI readings of about 2500-2700 fpm.  I made note of  the RPM and MAP while climbing through 4000 feet.  RPM was 5850, and MAP was 24.  I was running too rich because I turned up the mixture after my sag during the initial climb out, so the rpm was not what it normally would be (6200) , plus I should have recorded it at a much lower altitude.  Have I ever mentioned how nice it would be to have datalogging (Tracy???).   For an official climb rate, I descended to 1000 ft, established a climb at 100 mph, and timed from 1500 to 2500.  That took 25 seconds, which calculates to 2400 fpm.  Better, probably due to the cooler day, but still with full fuel.  Probably with a light load of fuel, and anytime other than right after Thanksgiving (overstuffed pilot), I could get this over 2500 fpm pretty easily.  For the time being, I’ll be happy with this, and will worry more about the oil temp. 

I made a full throttle run at 8000 feet to compare with Tracy’s numbers.  The TAS figure is the EM-2 readout, which I believe to be a bit on the high side.  No reason to believe the fuel flow figure either, since I haven’t verified it.  Both have the default settings, so maybe they’re comparable with Tracy’s readings (if he hasn’t changed his).

Alt          OAT surface         RPM       TAS        GPH

Tracy      8000        69                            7250        225          16            (best power mixture)

Rusty     8000        58                            6800        218          18.4         (mixture as set, forgot to set for best rpm)

Not sure yet what this all means, other than I was in a hurry and didn’t take the time to fiddle with the mixture, etc.  I still have some drag issues, since I’m missing the intersection fairings, and have yet to clean up some of the other airframe messes.