For what it's worth, here is a commentary on the .53.
AVIASTAR RS-53 C/L
By: Thomas J. Weedman
While I was at the Huntersville contest in October of 2008, Bob Zambelli asked me if I would be interested in testing the Aviastar 53 engine. Of course, I jumped at this wonderful opportunity, looking forward to being the first to experience the flying power of the new Aviastar engine. As soon as I got home, I picked out a profile airplane titled "Rampage" that was built in 1993 by Jim Mitchell of Orlando, Florida. I had purchased the "Rampage" several years back. Jim won several contests in the 90's flying this airplane and it was outfitted with a Super Tiger V-60 by Randy Smith. It has a 57 inch wingspan with 741 sq. inches of wing area and weighs 67 ounces.
The Rampage is an excellent flying aircraft and has never let me down. In my opinion it is one of the better airplanes in my fleet which consists of a collection of approximately 40 or so airplanes.
First, I had to retro-fit the aluminum motor pads because it does not have the same bolt pattern as the Super Tiger V-60. I did this by drilling and tapping the aluminum motor pads with a 440 bolt to the Aviastar bolt pattern. Then I had to remove the motor and bench run it to break it in before testing it on the plane.
This motor was fitted with an Aero Products P.A.65 needle valve assembly and a Sig Idle Bar Glow Plug. The fuel was Brodak 10% nitro with 11.5% castor oil and 11.5% synthetic oil.
The break- in props were an 11-4 Zinger and a 12-4 Zinger. The motor was run at three minute intervals for 36 runs from a cold start every time. The RPM with the 11-4 Zinger prop was at 9800 rpms, and with the 12-4 Zinger prop it was at 8000 RPMs.
The first propeller I used was a 12-5 Rev Up propeller. This turned out not to be enough propellers to pull the airplane with an Aero Products Super Tiger 60 tongue muffler, which uses the same muffler bolt pattern as the Aviastar. The propeller of choice is a 13 - 5.5 Bolly carbon fiber propeller (Aero Products). After several flights I added two head shims, and this provided a good 4 - 2 break run. This relaxed the motor to a good stunt run and it ran consistently.
Then I decided to try an Adamisin Expansion muffler. After several runs, I discovered I would need to add one more head shim, for a total of three head shims to get the 4 - 2 break I was looking for. This motor has a lot of power and can fly most .60 size aircraft easily. Fuel consumption was 5.5 to 6 ounces of fuel to fly the complete pattern.
The only thing I would suggest changing on the motor is the bolt pattern because no other engine that I could find (at least in my collection), has the same pattern. The closest thing I could find is the Super Tiger 51, which was the closest to the Aviastar pattern. If the bolt pattern on the motor was changed to something more practical, like the Super Tiger 51 pattern, more people could drop one of these fabulous, powerful motors in their airplane and have more standard power than they have with the Super Tiger 51. This motor will give their airplanes more stamina and punch for the long haul.
The Aviastar performed very well on the Rampage and it actually flew better with the Aviastar than it did with the Super Tiger V-60, which made me very happy. Even though I had to make a few modifications to make the motor fit the plane, it was worth all the effort in the long run.