Denis claimed 200-220 MPH TRUE at 18K. Still dang fast.
The main reason for the intercooler was to keep the air inlet temperature
below 160degrees
during the long climbs to 16-18K and in hot air temps. The 914 installation
has some cooling
problems and the intercooler helps address this. Plus, Denis was aiming for
a "BMW of the air"
which meant lotsa technical tricks. His plane has oxygen for 3 and a dual
100 watt/channel stereo
system. Plus air-adjustable seats filled by bleed air from the turbo.
Hooha!
Shaun
----- Original Message -----
From: "Fred Fillinger" <fillinger@ameritech.net>
Subject: Re: Re:914 intercooler
> In rereading the archives too, the only concern was questioning 220
> MPH top speed, impliedly due to only an intercooler. No question re
> some fuel efficiency, engine wear, and climb, but not cruise. There
> are intercooler "tech" papers all over the web. Claims vary (mostly
> auto enthusiasts but with access to dynamometers), but best I found
> was (for 100HP engine) 1.5HP per 10F degrees reduction in induction
> air temp. Assuming 50F drop, the math works out to about 4 MPH at
> 100% throttle cruise, minus effect of add'l cooling drag. Suspect
> you get a bit more above the magic 16,000 ft., with controllable-
> pitch prop, but altitudes much above that are not practical
> unpressurized, except now and then for the fun of it!
>
> I just read a cool (no pun!) way to look at it. Engine efficiency
> goes up with the spread between induction air temp and EGT: If you
> ingest 1600F air, same as EGT, the engine would produce no power. So
> reduce induction air from from 160F to 110F, and do the math, that's
> only a 3% increase in power and fuel efficiency, not 7.5% per above.
>
> Regards,
> Fred F., A063
>
> KarkelB@aol.com wrote:
> >
> > Hi Folks,
> > read an article in the forum archive about intercoolers
where
> > someone expressed concern about installing one.I spoke to someone at the
> > rotax factory who actually said that rotax do recommended the fitting of
an
> > intercooler to the 914 as it enhances its efficiency/performance and
reduces
> > the wear and tear on the cylinder heads. In addition to that one can
have the
> > maximum 115bhp for more than the stated five minutes at full throttle.
> > However he went on to say that should an intercooler be fitted it must
have
> > the flow rate as recomended in the 914 installation manual. And to cap
it
> > all, your warranty should not be affected by the installation. Thought i
> > should share this with all those with 914's craving better performance.
If
> > you are in england demon tweeks on 01978664468 have all sizes of
intercoolers
> > and can custom build some if you want infact they have one that is
similar to
> > Denis Vories,just seen it in their catalogue. Denis Vories installation
is a
> > real clean one folks!
>
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