Response below.

Craig,

Thanks for the info – much appreciated!

A few follow-up questions (if I can bother you with them, and if you have

the time)?

1.) Have you ran into any durability/detonation issues with 8.5:1 and 38" max boost? I am still building.  The engine should arrive this week. There are several engines built that are close to the same configuration as mine.  No problems to date. I was considering 8.5 and 42".  ICP's would probably be a little high.  What are you flying, unpressurized IV? IV-P  How many Hours?  Building

Typical cruise altitudes and Power settings?  We will see.  (25,000 at 32" LOP)

2.) "Looser" turbos (higher A/R ratio) are slightly larger in physical

size (bigger housing) than the std TCM/Garrett A/R=.5 turbos. That is what

I am considering. Are you using the larger/looser Mirage Turbos  Yes, Mirage Turbo.  or the Std

TSIO-550 A/R=0.5 turbos? Can you maintain 38" to 25,000 ft? Others report yes. Possible TIT issues?? Do you know the A/R of the Piper Mirage turbos (the A/R is typically cast into the

external turbo housing/face and will be obvious if you look closely – approx

½" font size) – I believe they are A/R=2.0 (unverified). No, but I'll check when when the engine arrives.  This week, hopefully.

3.) Was your engine originally a TSIO-550 with replaced pistons, or an

IO-550 with added turbos?   TSIO 550. where was the engine work done? Performance Engines. Was it dyno

tested?  Run in yes. Brake dyno, no. Max HP?   More than 350. Max Fuel flow? Will set in the plane at 350 deg ROP. Probably 43 gph or slightly higher  Cruise (75%) Fuel Flow?  Unknown

4.) Do you cruise LOP?  I will.  Do you agree with George Braly (GAMI and Co) LOP

theory / suggestions? Yes!!  I am an ex GM power train engineer.  (1000's of dyno hours)  George and company have done more good combustion event work than anybody I have ever talked to. If yes, any tips on "The Big Pull"? Determine a fuel flow and pull to that from then on. Calibrate ever once in the while. What are your climb settings (full rich)?  I'm not sure. Something to work out during initial flights. Depending on temps, I expect to cruise climb anywhere from 150 kt to 165 kt. to the flight levels.

5.) Can you provide any "typical" info on MP, RPM, Fuel Flow, & CHT in

various flight regimes?  Must defer to others flying.

6.) Do you know where your timing is set (less advanced than normal to

delay/reduce peek cylinder pressure/detonation)?  20-22 BTDC (Retarded from stock setting)

ceramic piston coating, Yes, I believe in the new ceramic coatings. mild port/polish, etc)? Yes TCM cast pistons or

aftermarket forged pistons? Forged. GAMI or TCM injectors?  Built with TCM, GAMI's will be installed.

8.) Why did you build your own intercoolers? To be different. Bigger? No, same physical size. More efficient? Yes, that is the theory anyhow.  More cooling for the same delta P.  Hopefully, these very expensive billet end caps will also reduce the delta P.  I designed and machined them, I can't bad mouth them.

Cowl/baffle arrangement?   TBD.  Any data on how much better they are (temp drop,

reduced flow restriction)?  Cooling will have to wait unless someone wants to test them.  Flow data coming.....top secret, you know.

9.) If you don’t have sonic nozzles (no bleed air), do you have an

exhaust muff for cabin heat?  IV-P will sonic nozzles. (Talk to TSIO 550 Legacy guys) Is it on the cross-over tube or on the short turbo exit pipes? How well does it work in the cold? Size/Source/Photo?

10.) Can you direct me to any "quasi-normal" Legacy owners flying with a TSIO-550 with the sonic nozzles plugged (Reno racers excluded). Everybody I know is a Reno racer.  See if Lynn Farnsworth is still on this list. I love to gather their experience also.

Well, I have already told you more than I know...I better stop. Craig Berland