Sender: <marv@lancaironline.net>
To:  lml@lancaironline.net
Date: Sun, 20 Dec 2009 19:34:34 -0500
Message-ID: <redirect-4032540@logan.com>
Received-SPF: pass
 receiver=logan.com; client-ip=74.126.18.170; envelope-from=lorn@dynacomm.us
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=dynacomm.us;
	h=Received:Subject:From:Content-Type:Message-Id:Date:To:Content-Transfer-Encoding:Mime-Version:X-Mailer;
	b=cj1wwIZYYLV6c4cWfx/fG0eyOBDsWPSV7SF+AszIxlU2u58rXXgkpuMZ7NfPTDq34BgqJIjC+V9KNsg3IkmVnpxBxwvTUuu3ZxZZ3Upd67rS5EYr1HYZQlLPbMGj0Kwb;
Subject: Re: io-550 vs. tsio-550 differences?
From: Lorn H Olsen <lorn@dynacomm.us>
Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes
Content-Transfer-Encoding: 7bit
Mime-Version: 1.0 (Apple Message framework v1074)

Is any waste gate really necessary?

Can't the throttle just be opened and kept at about 30"?

> From: George Braly <gwbraly@gami.com>
> Date: December 20, 2009 2:50:57 AM EST
>
> >>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<<
--
Lorn H. 'Feathers' Olsen, MAA, ASMEL, ASES, Comm, Inst
DynaComm, Corp., 248-345-0500, mailto:lorn@dynacomm.us
LNC2, FB90/92, O-320-D1F, 1,650 hrs, N31161, Y47, SE Michigan