Engine most suitable for current stunt requirements

[Casey]

Is an ABC or an AAC engine more suitable for present day stunt requirements?

[Randy Cuberly]

Is an ABC or an AAC engine more suitable for present day stunt requirements?

Either can work very well.  The AAC is obviously a little lighter and less common.

Engine choice depends on how serious you are and at what level you fly.

Randy Cuberly

[proparc]

.40-.50 in the middle.
.61-.75 up top.
Any configuration. Got to be quick starting, and VERY reliable-we operate close to the ground ALL the time.

[Tim Wescott]

AAC vs. ABC is a minor detail compared to all the other things that matter more for a stunt run.

Read the pinned threads in the Engine Set Up Tips section -- there's a lot to learn in there.

[Lauri Malila]

Absolutely AAC, preferrably integrated construction and of course with a Dykes ring . L

[FLOYD CARTER]

The vast supply of good used Fox 35s will last a very long time.

F.C.

[Juan Valentin]

   
           The newer AAC and ABC engines will cost more but they are better made with quality materials which will provide a lot of service if you take care of them and don`t crash them against a hard surface on a vertical dive. They are also light if specifically made for stunt with more power and a pretty good stunt run depending on your set up.
                                                                                                                                                                                                                                     Juan

[RandySmith]

Absolutely AAC, preferrably integrated construction and of course with a Dykes ring . L

Please do not send him looking  for that non existent ,commercially  NOT available  stunt motor  !!!!!     

Randy

[Robert Zambelli]

Brodak 40.

[RknRusty]

Brodak 40.

Bob, my limited experience with one B40 is that they're hard to crank. I've kind of shied away from them after one frustrating summer with the Brodak in our old arf Nobler. Wayne had a B40 in it that summer, but after he gave it to me I used my steel fp35. It had some minor cowl related heat problems leaning out during the V8 and staying lean to the end(which I kind of liked as a then low Int. pilot), so maybe that's all that was bugging Wayne's B40.
Rusty

[Keith Renecle]

Or..........you could just use one of these.........

[Steve Helmick]

Bob, my limited experience with one B40 is that they're hard to crank. I've kind of shied away from them after one frustrating summer with the Brodak in our old arf Nobler. Wayne had a B40 in it that summer, but after he gave it to me I used my steel fp35. It had some minor cowl related heat problems leaning out during the V8 and staying lean to the end(which I kind of liked as a then low Int. pilot), so maybe that's all that was bugging Wayne's B40.
Rusty

That's been our experience, for inverted mounted B.40's. Upright or side-mounted, they're fine. For an inverted B.40, you really should just begin by turning the plane over on its back. Since most of us have bad knees, that works better anyway.  Steve 

[Brett Buck]

Is an ABC or an AAC engine more suitable for present day stunt requirements?

   All of the really good current stunt engines (PA and RO-Jett) are AAC, but I wouldn't turn down an ABC or ABN that engine that ran well. The metallurgy is only a tiny part of the equation, the rest of the engine and the way it runs is determined by far more than what you make the cylinder out of. The 40VF is still the gold standard of stunt engines and it is ABN and lasts longer than anyone here will ever run one.
 
     For reference, "current stunt requirements" for an IC engine are still a rear exhaust .40-.76 two-stroke with schneurle porting and AAC/ABC liner, tuned pipe exhaust, turning a carbon fiber prop of around 3.5-4.5" of pitch in the range of 9500-11500 in the air. Anything else is really not in play - other engines can be made to work with acceptable results and a lot of unnecessary effort, but piped engines are stiil the best and probably the last competitive IC engine system.

    There will be many counter-opinions but those will be coming mostly from sport fliers and casual competitors, (and of course from manufacturer shills running astroturf ads as informational posts). That's not to say they are wrong for their particular application but is you are talking about competitive stunt in the year 2016, there is no real debate over what works best.

    Brett

[Randy Cuberly]

   All of the really good current stunt engines (PA and RO-Jett) are AAC, but I wouldn't turn down an ABC or ABN that engine that ran well. The metallurgy is only a tiny part of the equation, the rest of the engine and the way it runs is determined by far more than what you make the cylinder out of. The 40VF is still the gold standard of stunt engines and it is ABN and lasts longer than anyone here will ever run one.
 
     For reference, "current stunt requirements" for an IC engine are still a rear exhaust .40-.76 two-stroke with schneurle porting and AAC/ABC liner, tuned pipe exhaust, turning a carbon fiber prop of around 3.5-4.5" of pitch in the range of 9500-11500 in the air. Anything else is really not in play - other engines can be made to work with acceptable results and a lot of unnecessary effort, but piped engines are stiil the best and probably the last competitive IC engine system.

    There will be many counter-opinions but those will be coming mostly from sport fliers and casual competitors, (and of course from manufacturer shills running astroturf ads as informational posts). That's not to say they are wrong for their particular application but is you are talking about competitive stunt in the year 2016, there is no real debate over what works best.

    Brett

Brett is of course absolutely right.  To prove what he said you need look no further than the current results for Stunt at the 2016 National Championships held a few days ago!   I wish someone could collect the full list of the Top 20 Aircraft and Engine Setups and publish it.

Top Five was 2 electrics, and Three PA 75's with pipes.  The overall Champ was David Fitzgerald with a PA75 and pipe.

I suspect eventually the electrics will catch up and perhaps even surpass the piped engines.  They are probably about as good as a good IC setup now...but then they've been saying that for about 5 years.   

A lot of the success is of course still in keeping the "Nut on the handle" tight.   

Randy Cuberly

[RknRusty]

A lot of the success is of course still in keeping the "Nut on the handle" tight.   
Randy Cuberly

Hahaha, damn Randy thanks, that must be what I've been neglecting to do.

[proparc]

  
     For reference, "current stunt requirements" for an IC engine are still a rear exhaust .40-.76 two-stroke with schneurle porting and AAC/ABC liner, tuned pipe exhaust, turning a carbon fiber prop of around 3.5-4.5" of pitch in the range of 9500-11500 in the air. Anything else is really not in play - other engines can be made to work with acceptable results and a lot of unnecessary effort, but piped engines are stiil the best and probably the last competitive IC engine system.

   Brett

Basically what Brett is saying is that, if you want to whip some a@#, you need the PA 75.

[FLOYD CARTER]

 Current (sic) reports show electrics also doing some "whipping".  Just because the present champ uses a PA on a pipe, doesn't mean one "must" do the same.  Try it, if you must.  But don't expect the magic you assume.

F.C.

[proparc]

Current (sic) reports show electrics also doing some "whipping".  Just because the present champ uses a PA on a pipe, doesn't mean one "must" do the same.  Try it, if you must.  But don't expect the magic you assume.

F.C.

You can check my post about "the back and forth like F3A".

[Motorman]

I'm holding out for one of those new Brodak 61's.


MM

[Dennis Moritz]

Orestes just won the World with electric. Paul Walker won recent NATs flying electric. Electric is on par with the best of IC, in ways superior. David Fitzgerald flew better this year. Pilot. His piped engine powered up accurately where shape making most benefited. When the IC big blocks are working best, keyed to conditions, they appear to have more drive. Electric devotes will disagree. Perhaps the flick flick millisecond thrust changes enabled by the Igor System are blunted in their effects by the size (weight and aerodynamic drag) of serious CL Stunt War wagons. This years NATS made me think of airplanes as boats swimming in air. Steered through direction changes more softly than cars, for instance, stuck to to the road. Perhaps the millisecond changes enabled by electric power with computer enhancement will not dominate CL Stunt, after all. A friend said, however, that electric is now the sole power for serious RC Aerobatics.

[Terrence Durrill]

That's been our experience, for inverted mounted B.40's. Upright or side-mounted, they're fine. For an inverted B.40, you really should just begin by turning the plane over on its back. Since most of us have bad knees, that works better anyway.  Steve 

              And I thought I was the only one with really, really bad knees......really bad!       

[Steve Helmick]

The OP didn't ask about motors. Just sayin'.  Steve