lml@lancaironline.net Mailing List Archive

Hi Gary,

I am planning on a manual wastegate because I am a cheapskate. I used to have one on my Mooney and it worked great. I would really like to have intercoolers because I saw some really high induction air temps on my Mooney. It wasn't until you got up to 20k or higher though. Not having them might make sense, it would save the cooling drag as you say. I don't plan on flying above 21k feet (above this, cannulas loose there effectiveness on me and my girlfriend). I suppose I could try it without intercoolers to begin with and add them after the fact. It would limit how quickly I could climb to those high altitudes though. Of course by limit I am guessing I would have to reduce my MP/boost/climb rate to 1500fpm from 2000fpm after 12000 feet or so. Probably not that big a deal, I guess. Hmm. decisions, decisions.

Matt

From: Gary Casey <casey.gary@yahoo.com>
To: lml@lancaironline.net
Sent: Thu, December 17, 2009 7:11:43 AM
Subject: [LML] Re: io-550 vs. tsio-550 differences?

Here's another thought: A lot of it might depend on your intended usage. If you want to go really high (over 20K) and have maximum performance you might want to consider getting the extra power of the TSIO-550. But if you, like me, might limit altitudes to less than 20K and are more cost and fuel economy sensitive, then a lower tech solution might be in order. I flew for many years behind a Lycoming O-540 that was turbonormalized (C-TR-182) and it worked quite well. It didn't have an intercooler or automatic waste gate - the waste gate was connected to the throttle linkage so there were no extra levers. It was fed by a pressurized carburetor, so that doesn't apply with a Continental. So the question is, what's wrong with using a standard IO-550 with a turbo and manual waste gate? The Lycomings don't bother with a sniffle valve, so there isn't any difference between turbo, fuel injected, or naturally aspirated engines in that regard. At 18,000 feet the use of an aftercooler has real, but marginal benefit, as the extra aerodynamic drag and pressure loss negate most of the charge-cooling benefit. Just a thought, suggesting a KISS methodology.

Gary

Yes, but can you fit it into a Legacy cowling????

----- Original Message ----- From: "George Braly" <gwbraly@gami.com>
To: <lml@lancaironline.net>
Sent: Wednesday, December 16, 2009 10:02 AM
Subject: [LML] Re: io-550 vs. tsio-550 differences?

Ah... you could buy a TN IO-550 engine and have exactly what you want.

It already has all of that stuff you are worried about.

Intercoolers, fuel pump, throttle, GAMIjector(R) fuel injectors, pressurized magnetos, and all the little details.

There are over 900 of them flying, and parts support is superb (ask me how I know).

They have better intercooler efficiencies than the TCM TSIO-550.

They run on significantly less fuel than TCM TSIO-550s at the same BHp.

They run cooler than a TCM TSIO-550 at the same BHp.

They can be made to run at VERY high horsepower (Sport Class winning BHp levels at Reno if you find someone who really understands the engines and knows how to get them set up right for that demanding activity.)

And they are able to use an electronic waste gate controller designed for that engine.

There is a pending STC application with the FAA to authorize their use on certified aircraft with G100UL fuel.

I know where one complete engine and turbo system is sitting, ready to be installed.

. . . Just a thought.