Aaaand on the way home, we got to test an improvement to the intercooler setup which I did during the last annual.
(Intercooler performance of the Extra 400 is poor and this was the first limiting factor on a hot day, especially in the climb).
We were at MTOW and temperature was ISA +9 – not hot but already significantly warm – aaaaand…
… tadaaaa:
We kept full climb power until FL200 (37.5 inches, 2500 RPM – 88% power) and maintained a climb rate of 1000ft/min while keeping inlet air at 130 F max.
Airspeed was around 115 KIAS and FF at 126 litres per hour. CHTs were below 270F (not a typo).
Even more great news: above FL200, and all the way to FL240 – our cruise FL, we only needed to reduce climb rate to 800 ft/min and all temps were in check.
The mod – my 3rd attempt – is really minor, so I am delighted – the intercooler is finally intercooling as it should 
I’d like even more intercooler efficiency – this is really the limiting factor on a properly set-up Extra 400. Quest not over.
Happy camper here!
@FrankD
We did not do any performance comparisons, We were busy enough avoiding collision, it was my first formation flight.
How are you progressing?
Great news and results on the intercooler!
What did you do?
Nice pics btw
denopa wrote:
What did you do?
Nice pics btw
Vanes that turn the airflow 90 degrees inside the airbox.
Thank you for the compliment!
Beautiful photos 
And so rare to find two of these together.
Yes indeed Peter,
This was not just luck, it was a planned encounter and we have decided to try and do a real Extra 400 get together with maybe four or five birds!
I had very little experience with formation flying and I must say it’s really exhilarating
@Flyingfish
The interior is now entirely stripped out, except the panel. We have another delay waiting for the estate of the previous owner to complete all of the paperwork with their lawyer and the FAA to transfer ownership. Very frustrating, we are on hold until that is resolved. It looks like the Garmin G500 Txi is the best viable panel option.
I wish you success. Are you going to keep or replace the engine ?
As to avionics, there’s already one G500 TXi install under N-reg in case it is not on the AML and you need to reference it for a Form 337.
Since your cabin is stripped off, I suggest a complete redesign of the cabin climate setup. The factory setup is… er… below 2020 expectations…
You’ll need heating in the footwell during economy cruise at high altitude – the pressurized air venturi is located downstream of the intercooler and so cabin air is not warm enough.
Maybe floor heating using IR panels?
Seat heating in mine works great, except the very expensive certified 12V power supply has recently adopted the duty cycle of a french union leader.
AC is brutally crude, they did improve it (a little) in the Extra 500, so may be worth a look in the AMM.
Honestly it would be best to get a modern climate control system installed as a major mod!
I am going to begin with the existing engine and see how it works. It seems to run strong. I greatly appreciate the information on the key changes you have made to get the performance you have attained. Do you have detail on the intercooler vanes? I will reach out to you again as I start FWF work. I will also look at the AC and heat alternatives, but I may wait until I shake out basic performance to invest that effort.
Ok, let’s connect when you are this far.
You are absolutely right in trying to keep the TSIOL550.
I honestly believe it is an amazing piece of engineering, poorly manufactured and catastrophically installed and maintained.
If you are lucky enough to have a set of “good” cylinders (i.e. no major manufacturing defects leading to premature cracks) and you know how to make a WATER cooled engine work in an aircraft, you’ll be miles ahead of anything air-cooled in this power range.
PS: Since you’re at the beginning of the journey: I have once calculated how many thousands of work hours went into Galatea since I picked her up. You would not believe it. Probably enough to build 3 homebuilts!
