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Date: Sun, 04 Nov 2007 09:35:01 -0600
From: David Staten <Dastaten@earthlink.net>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: MAP port location \
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If you are boosting, you REALLY REALLY need to consider intercooling. 
You're maybe adding 100 or more degrees of heat to your intake charge, 
which predisposes you to detonation. ESPECIALLY in your setup with high 
compression rotors. Turbo/ blown installations are typically low 
compression in order to avoid detonation margins.

When we are talking about "normalizing" at 8000 feet, you are increasing 
the air density by about 30%. Thats a lot for an non-intercooled 
installation. Thats a lot of extra heat. One episode of detonation and 
you will be spending more than the cost of an intercooler in order to 
rebuild and tear down the engine.. and perhaps replace housings that get 
chewed up by shattered apex seals.

I'm not saying this is dangerous, but its two strikes against your 
engine in current livery.
Dave

George Lendich wrote:
> Bobby,
> I know your planning only normalizing with the Turbo, but my concern 
> with the 10:1 high compression rotors is that you might get into 
> detonation - especially without an intercooler.
> Then again I'm no expert, that why I would like to know the safe boost 
> level as well.
> I recommended the 3mm apex seals because of my concerns of detonation, 
> not so much the loss of hp.
> George ( down under)