Based
on the relative insensitivity of the Renesis to backpressure, a
turbo was installed on the test stand Renesis. I had previously
installed the same stock 1988 RX7 turbo on the test stand 13B and
observed a large penalty in efficiency at cruise power levels.
As a result, I had lost interest in a turbo option. At the rotary
gathering this fall, Bobby expressed an interest in how the Renesis would
respond to a turbo. So some data was collected in this regard.
Those present at the rotary gathering may recognize the plot of data that is
attached. It showed the power generated with a 13B normally
aspirated (NA, red), supercharged (SC, black), and turbocharged (TC, lighter
blue). Data from the normally aspirated (NA, green) and turbocharged
(TC, darker blue) Renesis has been added to this plot. The results
seem remarkable in that there appears to be no penalty at cruise power for the
turbo installation on the Renesis other than weight and
complexity.
The
data by no means represents an extensive study, but the difference in response
of the Renesis to the turbo compared to the 13B seems worthy of
reporting. Field elevation here is 7200 ft with DA normally above 8000
ft which limits normally aspirated MAP to 23" Hg at WOT. An intercooler
was installed on the test stand for both engines. No attempt to boost
the Renesis above 30" MAP was made. It is also unlikely that the
turbo tested would be the best match for this application. Any thoughts
on identifying an appropriate turbo would be welcome.
Steve
Boese
RV6A,
1986 13B NA, RD1A, EC2
From:
Rotary motors in aircraft [flyrotary@lancaironline.net] on behalf of Stephen
Izett [steveizett@me.com]
Sent: Tuesday, January 01, 2013 7:23
PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re:
turbo manifold
Steve
Did that engine end up
turboed?
I have a Renesis, hopefully
flying in the next 6 months but am seriously interested in turboing it down
the road.