Clarence:

   Which company makes the better 4 stroke engine, OS or Saito?  Also, do you think Thunder Tiger 4 strokes are as good as either OS or Saito?  I'm talking about quality and power output.

   Also, what is the advantage of buying an OS .91 4 stroke engine with the pumped carb?  It appears from the Tower Hobbies website, that the pump does not give the engine any more horsepower.  I'm assuming that the pump is there to assure that the engine doesn't die out in certain maneuvers where the airplane is in a different attitude that might starve the engine of fuel.

    I am going to be buying a 4 stroke engine for an Extra 300, and a Great Planes Seawind amphibian.  The Seawind is designed around the OS .91 mounted inverted.  Do I need the pumped carb if the engine is mounted inverted? Or, is the pump only an advantage where I am powering a highly aerobatic plane like the Extra 300?

Thanks for your help,

William

Dear William,

O.S.has always set the standard for quality among the model engine manufacturers. Some have equaled, but none have surpassed. Actually this boils down to case of personal opinion. Which

do you like best - Ford or Chevrolet? The Saito and Thunder

Tiger are also excellent quality engines that usually sell for

a little less money. A fellow named Kaz Mihara was at one time President of O.S. until he and the directors had a difference

of opinion on the direction the company should take. Kaz quit

and is now in charge of design and production at Thunder Tiger. As such there is a lot of similarity between the Thunder Tiger and O.S. engines.

The advantage of a pump is non critical fuel tank placement

and less chance of the engine leaning out during more violent maneuvers. Usually a larger throat carburetor is used resulting in a small increase in power. The pump is not going to do anything for you with an inverted installation other than the advantages previously mentioned.

Yours,

Clarence Lee