60 Hour Inspection : RV-7A, RX-8 Renesis engine, James Rotary Cowl, Radiators under engine

As of January 08 I've flown my Renesis powered RV-7A about 60 hours.  At the 60 hour mark I did a detailed inspection of the intake and exhaust systems as well as everything else under the cowl.
I found no cracks or other problems with the exhaust system!!  The heat shield between the muffler and the left cowl had lost one attachment screw- no big deal.  Attached are pictures of the exhaust.  I use a stock RX-8 exhaust manifold - a 4 in dia. X approx. 6 inch long swirl pipe(see third picture) to redirect the exhaust from the front to the rear of the  plane and a Flowmaster Hushpower Resonator (PN - 12512400) as the exhaust muffler.  Everyone who hears the airplane fly comments on how quiet the engine is - neighbors call it the Stealth Rotary RV!  It is super quiet compared to my neighbors 180 Lycom. RV-7A.   I don't know if the Flowmaster muffler will withstand the exhaust pulses from the RX-7 engine rotors but I feel confident the muffler will work with the Renesis.  Mark Steitle with his 20 B engine and Flowmaster resonator will have first hand knowledge soon!

I had previously found that one EGT probe extension wire melted - it was about 8 inches from the exhaust system.  The probe wires leads were not damaged but the extension thermocouple wire from A/S had insulation that melted from the exhaust heat.  I have rerouted the extension wire to keep it away from the exhaust.

There were no problems with the intake system. It is fabricated  using part of the RX-8 manifold  and a home-made intake plenum.  I used the stock injectors, fuel rails and injector locations.  The fuel pulse damper was removed! (Pictures in next E-Mail)

I did find several very small oil leaks in the casting of the PSRU.  I'll confer with Tracy as to how to address these.

I used the James Rotary Cowl - same one as the Power Sport rotary used - mounted my oil and water radiators underneath the engine, bought an engine from a wrecked RX-8  with less than 10,000 miles on it.  The engine was not disassembled.   I also used (with some modifications) the exhaust, intake, fuel injection parts, spark plugs, plug wires, coils, 100 amp alternator, oil injecton with Richards adaptor,  water pump and water outlet system with the thermostat removed. (See attached pictures)

I will be adding a cowl flap to keep the oil and water temps. cooler in the hottest summer and warmer in the coldest winter temperatures.

My prop is a Catto 76 in. dia X 88 in. pitch and my max. cruise rpm is only 6200.  I am over- propped for the HP currently being produced.  This does allow me to cruise at rpms around 5400 when I want to go fairly fast and keep fuel flow down.

My intake and muffler systems could be improved to raise HP.  I've been flying side-by-side with my neighbors RV-7A with a Lyco. 180 HP engine and a metal fixed pitch prop.  At the same take-off weight we climb about the same rate and in cruise we are about the same speed.  I believe I will be slightly faster above 8000 feet alt. in cruise.

My success so far is in large part due to the contributions others have made to my project by posting - their successes and failures, thoughts, knowledge, suggestions  and references to other sources - to this list!!!

A Special "Thank You" to Ed Anderson, Lynn Hanover, Al Gietzen and all the other contributors  for all the great knowledge they bring to the rotary group!

Dennis Haverlah