"Parlow, Eric (Turbos-Asheville)" wrote:

I'm building a RV-8A.

I would like to use a turbocharged 20B with 2.85:1 and CS prop.

Planning for 350 bhp climb & 200 bhp cruise to 12k ft.

What challenges am I facing?

Eric Parlow
RV-8A

In regard to the engine not many. You need a motor mount and cooling
system. As I recall Tracy Crook is building a similar but NA
combination. Feel free to ask any questions on here. The big thing
before you start is build a full size mock up or get 3D software
to make sure everything fits where you think it is going to fit.
You will have to build a 20B turbo manifold because as far as
I know there is nothing off the shelf. There are signs that
there will be a low profile intake manifold available.

Paul Lamar

That's going to be a real performer Eric!
Just wondered about your choice of the 2.85 ratio.  Some people want the
additional engine rpm that a 2.85 ratio will allow (for more HP) but since
you are turbocharging, you can easily meet your HP goals without reving the
engine past 6000.

Also, ask a few prop makers what they have available that would work
efficiently at 74" long , 2100 rpm and 350 HP.  You may be surprised at the
answer.

Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com

Why are 2100 RPM and 74 inch props magic numbers Tracy?
You have my mystified.

Paul Lamar
 
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