RE: Best Engine for GP Revolver?
There were four choices of engines given and I was trying to steer beachbrada away from the mistake I made on the Saito 82s.
And yes beachbrada, some folks like the sound. Some warbird racers use 4 strokes because the rules give a displacement handicap to the 4 strokes which was quite fair....until the advancement of the YS supercharged engines and now that's about all you’ll find in gold class.
airraptor:
"If saying an 82 is = to a 50 two stroke then that’s good for the four strokes it used to be that you had to double the cubic inches to have the same power ie: a 1.20 four stroke would be = to a .60 two stroke."
FF;
(The 82 is stronger than most engines in its class, but I believe it was at the expense of fuel economy and loss of smooth low idle, an aggressive cam? For the amount of fuel it used I could have ran two 55AXs. If you have the 82 in a clean plane and it propped for speed expect two things, #1 When you let go of the plane it will roll, so be ready to take off, kill it or chase it down. #2 Unless you have a 600' runway, dead stick landings will be the norm.
From what I’ve seen, the other size Saitos seem to run sweeter.)
“the 4's are more efficient when it comes to props because of the lower speeds and larger dia.'s 4's sound quieter but are generally louder on the meter, which means the 4's are easier on the ear's.”
FF;
(Fast or quieter, hummm, let me think? I’d go electric)
“If and when I get one of these I will put the saito 125 in it and swing a 15x8.”
FF;
(Like hot landings, nose over’s and tall landing gear?)
“Ido port work on mine 4's. my saito 65 turns an 13x8 apc at 9,400-9,500 about the same as OS 91 f's “
FF;
(Is the 91 sick or is that the way it is? = 1.23HP)
“the 4's are close if not easier on gas for the same given power. the two strokes lose some fuel out the exhaust.”
FF;
(Yes good 4strokes do have better fuel economy for the same power output, but what about physical size and power to weight?)
“A OS 70 should put you at around 90 on this plane and sip fuel.”
FF;
(With an OS FS 70 and an APC 11X10 or 12X7(unloaded 13K..close enough) the numbers work. Is 90 fast?)
It looks like we will only agree on disagreeing. Oh well different strokes for different folks,….sorry about the pun.[&:]