Received-SPF: none
 receiver=logan.com; client-ip=207.228.42.15; envelope-from=drwalker@gbis.com
Message-ID: <4B6E23C5.9070207@gbis.com>
Date: Sat, 06 Feb 2010 18:21:57 -0800
From: Don Wallker <drwalker@gbis.com>
User-Agent: Thunderbird 2.0.0.23 (Windows/20090812)
MIME-Version: 1.0
To: flyrotary@lancaironline.net
Subject: N.A. Renesis to turbo
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Dear list, Turbo flyers and especially David Leonard,
    I've 16 flying hours on my RV-8 with a Renesis and all of Tracy's 
stuff and a Catto 76/88.  The airplane flys great, just like an RV, no 
gliding time, and about 36 hours on the ground. 
SPECS
Full throttle 8,000'   174 mph indicated, 2450 on the prop, water 185, 
oil 205,
Climb out 110 mph, rate of climb, 1250'/min.  Field elevation 5046.

These are not bad numbers, but I would like better.  I've been 
influenced by some of the the local jet jocks who say that there is no 
such thing as too much horsepower and they are right!   N113BR seems to 
be performing about like a 160-170 HP RV.  So I am investigating 
turboing it!  The idea is to have a little better than sea level 
performance on take off (designed for 210HP N.A.) and turbo normalizing 
at cruise.  Up to 12000' would be nice.
During the air races this year, Dave Leonard showed up and I was very 
impressed by his airplane.  He was able to turbo and inter cool it and 
have it all inside an RV cowl, so I'll  likely base my installation on 
his.  Plus, he has been through the learning curve of 3 or so turbos so 
he knows what to do, what not to do and what would be better if he were 
to do it all over again.

I've spent the afternoon looking through the archives, reading as much 
as I can find about turbos, and downloading all the photos I can.  Here 
is what I am tentatively planning  on doing.
Get one of Techwelding's Renesis exhaust flanges made from 304 SS and 
have my local waterjet guy copy it and make one out of 321SS.  I'll weld 
321 SS and  manifold it together and run it into the bottom of the turbo 
that will sit right in front of the exhaust.  The turbo will have 
additional support.  Run the turbo outlet air from it through a stock 
RX-7 inter cooler sitting in front of the left cheek opening and then 
out to the right side of the engine, probably routing it under the PSRU 
and then up to a throttle body and manifold.  Then four al tubes over 
the top of the engine into a cut down and welded up stock RX-8  intake 
manifold.  The exhaust out of the turbo will run down and out in the 
usual center of the back of the cowl opening.  I am thinking of trying 
one of Burns Stainless all SS mufflers.  It is basically a glass pack, 
but instead of glass, they are using stainless steel wool and they say 
it is holding up for the rotary racers.  They make it any length you 
want and is about 4 lbs with their SS vs 9 lbs with the hushpower 2 I'm 
using now.  The combustion air intake to the turbo will be on the aft 
left side of the cowl via an NACA duct opening as Dave's is.
The oil cooler will have to be moved to under the engine.  I will build 
up a fiberglass scoop, probably based on Van's scoop and modify it to 
have a bigger opening and be farther forward, closer to the prop.  I 
will probably  have the oil cooler made a little larger (Techwelding) 
than the one I have now.

That's the basic idea at this point.  I'll finalize my plan, prebuild as 
much as possible before tearing the airplane apart and try for as little 
down time as possible.  I'm looking for the list's critique here, plus 
questions that I will have missed.  The following are a list of 
questions that I have.
1. Which turbo should I use, which orientation and who should I use to 
do the work, plus what is the approximate price?   TO4 hybrid?  Dave and 
Steve Brooks mention BNR turbo as a modifier.  Who manufactures the turbo?
2. What is the ideal situation with a waste gate?  Full open or not, or, or?
3. I read about a N.O.oil line solenoid to the turbo bearings.  I assume 
that if the Turbo fails, you turn it on to the N.C. position to prevent 
oil from being pumped down your exhaust?  I assume the oil that is used 
is routed back to the sump.
4. What size exhaust is optimum?  It seems Dave is running 2.5 inch.
5.  What size throttle body should I use and what would be a good one? 
One throttle body or two? 
4.  What size injectors should I use, and where should the secondaries 
be placed?   Dave is using 480cc and staging is at 32 inches.  Are you 
using the same for the primaries and is there an idle problem with the 
larger injectors?
5.  Anyone out there turboing a Renesis?  Anyone flying one?
6.  My compression is 9.7 to 1.   Any problems with this higher 
compression ratio as long as I use an inter cooler and keep the boost no 
higher than 35"?
And lot more questions, but that's all I can think of now.
So If any of you can add any thought, let me know.

Don Walker