New OPS stunt Engines rear exhaust piped .40 and .60

[George Buzel]

Great news, OPS is manufacturing rear exhaust piped stunt engines, .40 and .60 weight is in the 12 oz range, I'm in direct contact with OPS, any recommendations on exhaust timing and Venturi size respond to this post.

regards,

Buzzplane

[Brett Buck]

Great news, OPS is manufacturing rear exhaust piped stunt engines, .40 and .60 weight is in the 12 oz range, I'm in direct contact with OPS, any recommendations on exhaust timing and Venturi size respond to this post.

  OPSs were one of the first common piped engines, interesting to see them back. This isn't another MECOA deal, is it?

   You should probably get in touch with Bobby Hunt, he and Billy Werwage were the experts on them back in the day. I would guess the venturi size should be the choke area equivalent of about a .270-275 venturi with an ST needle, and I would want a .265 and .280 for experimentation purposes. That would be for either engine, we have been running more-or-less the same choke area on engines from a .20 to a .75 (actually, Dave's 75 is a bit smaller than the stock 20FP in terms of choke area).

   Any idea on the exhaust timing, intake duration, etc? If it fits in a 40VF or PA or RO-Jett 61 mount I would be willing to try it out.

   Brett

[RC Storick]

Or get ahold of the builder of many of those engines Randy Smith.

[Bill Morell]

Great news, OPS is manufacturing rear exhaust piped stunt engines, .40 and .60 weight is in the 12 oz range, I'm in direct contact with OPS, any recommendations on exhaust timing and Venturi size respond to this post.

regards,

Buzzplane

While I think this is good news I have to ask why? Seems the current trend is for going electric. I never will as it doesn't appeal to me.

[proparc]

While I think this is good news I have to ask why? Seems the current trend is for going electric. I never will as it doesn't appeal to me.

OS Max has just made one of it's largest committments to I.C, with it's new AX line and it's new 4 stroke Alpha line. There selling like gangbusters. It seems every time I check the Enya website they always have a "sold out" tag on some their motors.  Gas motors in the 20-50 cc range are red hot in RC,(OS max and Saito are pursuing this market very aggressively).  There seems to be a market surge in large radial engines -no doubt due to the increased availabilty of large warbird ARFS. The most complete "takeover" of electric in just about any competitive sector,(excluding RC park flyers) is in F3A yet, the YS 175 is still stopping them cold at the very top. The supercharger on that thing is rough.

[Bill Morell]

But are any of the OS engines for U/C? The sold out tags on ENYA have been there for a few years. Why? Because they aren't making most of them anymore. When they had that last surge for some of the "older" engines it was using up their parts inventory. I asked Ken Enya if they were going to produce more and he said no. The engines that you cite as being "red hot" are primarily for the R/C market. Look at the what most of the top fliers at the Nats this year are using, mostly electric from what I have seen. That is why I ask why.

[Bill Little]

Hi Bill,

I still believe it will be a while before IC engines completely die in C/L stunt.  I understand the cost is broken down over usage, but the initial outlay can still be beyond many of us.  Especially if we have some very good IC stunt engines.

Bill

[Bill Morell]

Hi Bill,

I still believe it will be a while before IC engines completely die in C/L stunt.  I understand the cost is broken down over usage, but the initial outlay can still be beyond many of us.  Especially if we have some very good IC stunt engines.

Bill

Hello Bill, no argument from me on the IC engines. A plane that is silent when flying just seems wrong from my point of view. I have always been most impressed with the guy that knows exactly how much fuel to use to avoid over/under runs and don't see much challenge from a electric motor with a timer on it. Just MHO.

[proparc]

The engines that you cite as being "red hot" are primarily for the R/C market.

Everything I stated was in reference to the RC market. But Bro, don't think you can't still throw it down big time with a good I.C. motor in stunt. Remember, a PA or Saito,(notice how I slipped in the Saito LOL) in the hands of someone that knows whats up, is going to take care of plenty business. You go up against a cat with a Merlin that knows what time it is, and you better have a damn good electric motor in that nose.

[George Buzel]

Hi Brett Buck,

Thanks for the information, I,m working with Max M. from OPS so we can design what we need in a engine, if you are willing to work with us I'm sure we can get a few engines to test for Max, the .40 will use the same case as the original SPA, but all other parts will be new and much improved tolerances and material from the 80's, On the timing I will email him Monday however I would like to go back to him with some numbers,  feel free to give me a call on this project for OPS my work number is 203 383 6483, I'm a engineer for Sikorsky aircraft, My home number is 203 452 9586.

regards,

George Buzel

[Brett Buck]

Thanks for the information, I,m working with Max M. from OPS so we can design what we need in a engine, if you are willing to work with us I'm sure we can get a few engines to test for Max, the .40 will use the same case as the original SPA, but all other parts will be new and much improved tolerances and material from the 80's, On the timing I will email him Monday however I would like to go back to him with some numbers,  feel free to give me a call on this project for OPS my work number is 203 383 6483, I'm a engineer for Sikorsky aircraft, My home number is 203 452 9586.

    It would need to fit in a OS 40VF/PA/ROjett 61 mounts for me to do anything with it in a useful amount of time. Otherwise, might contact Bob Hunt, I am pretty sure he has some airplanes that will fit the SPA mounts. I never had an OPS back in the day so I have no idea if the mounts are close enough to compatible.

    Brett

[RandySmith]

I built and converted many many of the OPSs back years ago for many flyers, I made many AAC versions, a very good 40 , it does not fit where a OS or PA goes

Randy Smith

[proparc]

To Bill Morel

See you can still take of serious business with an I.C.


Quote from Dave Trible

Ready?  I'm proud to announce:

1.  Doug Moon

2.  Paul Walker
3.  Bob Hunt
4.  Kaz Minato
5.  Bill Rich

Congratulation to Doug and all these fine gentlemen'.