Tom Martin
Well Known Member
Over the last month I have been working with Rod Bower, http://www.ramairforhomebuilts.com/ , doing some testing using his system on my EVO Rocket. We first used his standard air box and air valve and for my installation it was not quite right for the 540 engine. The filtered air was too restricted at high power settings and the ram air valve was also a bit undersized.
I use a chase plane, Wayne Hadath in his rocket, to determine the effectiveness of any modifications that I make to my plane. In the past, at altitudes of 8000 feet I used to show half an inch more manifold pressure then Wayne did. When I first installed the RAM air system I was not seeing any real improvement on those numbers compared to my previous system. Rod rose to the challenge and had a larger air box with bigger reed valves made. He also got a larger RAM air valve that has helped with flow. Yesterday Wayne and I did another test and I now have a full inch more MP then he does for an honest improvement of half an inch of MP using the RAM air system. With my previous filtered inlet setup I had not flown beside any other rockets that had a greater MP,so improving on that one is a real improvement.
The filtered take off performance is now on par with my previous system but when you open the RAM door you can feel and hear the difference. Thank you Rod for going the extra mile to make this system work properly with my engine.
I use a chase plane, Wayne Hadath in his rocket, to determine the effectiveness of any modifications that I make to my plane. In the past, at altitudes of 8000 feet I used to show half an inch more manifold pressure then Wayne did. When I first installed the RAM air system I was not seeing any real improvement on those numbers compared to my previous system. Rod rose to the challenge and had a larger air box with bigger reed valves made. He also got a larger RAM air valve that has helped with flow. Yesterday Wayne and I did another test and I now have a full inch more MP then he does for an honest improvement of half an inch of MP using the RAM air system. With my previous filtered inlet setup I had not flown beside any other rockets that had a greater MP,so improving on that one is a real improvement.
The filtered take off performance is now on par with my previous system but when you open the RAM door you can feel and hear the difference. Thank you Rod for going the extra mile to make this system work properly with my engine.