Circa 1982 O.S. VF .46
07-24-2005, 07:04 AM
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Circa 1982 O.S. VF .46
After sitting on the shelf in its dark blue box for nearly 23 years, this engine was finally run up last week.
To say I was hugely impressed with this old engine would be an understatement. The figures were as follows:
Engine: OS .46 VF
Fuel: 15% Nitro, 18% Coolpower Pink
Plug: OS #8
Pipe: Macs .60 Tuned Pipe (#1160)
APC 12.25 x 3.75: 13,900 rpm
APC 11 x 6: 13,900 rpm
APC 10 x 7: 15,100 rpm (compared with 14,400 rpm with open header)
APC 12 x 6 - about 9,900 rpm with pipe length used in above runs (engine couldn't "stage" on pipe)
APC 12 x 6 - once pipe lengthened to get engine to stage - 12,000 rpm
She might be an oldie, but she's a goodie!
To say I was hugely impressed with this old engine would be an understatement. The figures were as follows:
Engine: OS .46 VF
Fuel: 15% Nitro, 18% Coolpower Pink
Plug: OS #8
Pipe: Macs .60 Tuned Pipe (#1160)
APC 12.25 x 3.75: 13,900 rpm
APC 11 x 6: 13,900 rpm
APC 10 x 7: 15,100 rpm (compared with 14,400 rpm with open header)
APC 12 x 6 - about 9,900 rpm with pipe length used in above runs (engine couldn't "stage" on pipe)
APC 12 x 6 - once pipe lengthened to get engine to stage - 12,000 rpm
She might be an oldie, but she's a goodie!
08-03-2005, 01:12 AM
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RE: Circa 1982 O.S. VF .46
Steve, you already have - you just need a pipe!
Dave's just-run-in .50 SX with a pipe: 12.25 x 3.75: 14,300 rpm
John's just run in ASP .52 with the same prop and pipe: 14,200 rpm.
My OS .46 VF with the same prop on the same day: 14,100 rpm.
Dave's just-run-in .50 SX with a pipe: 12.25 x 3.75: 14,300 rpm
John's just run in ASP .52 with the same prop and pipe: 14,200 rpm.
My OS .46 VF with the same prop on the same day: 14,100 rpm.
08-10-2008, 05:10 PM
#4
RE: Circa 1982 O.S. VF .46
Harry,
After reading your post I finally dug out my old OS.46 VF, essentially new in the box after all these years. I'm just starting to break it in, so I only have a very few minutes of run time
Engine OS .46 VF
Fuel Powermaster 15% nitro, 18% oil + extra castor
Plug K&B idle bar until broken in
Prop Master airscrew 10x6
RPM, open exhaust 15,600
RPM, mousse can pipe 14,400
If I can't get the RPM up with the mouse can, would you recommend going to the MAC's pipe?
Thanks,
Bob
After reading your post I finally dug out my old OS.46 VF, essentially new in the box after all these years. I'm just starting to break it in, so I only have a very few minutes of run time
Engine OS .46 VF
Fuel Powermaster 15% nitro, 18% oil + extra castor
Plug K&B idle bar until broken in
Prop Master airscrew 10x6
RPM, open exhaust 15,600
RPM, mousse can pipe 14,400
If I can't get the RPM up with the mouse can, would you recommend going to the MAC's pipe?
Thanks,
Bob
08-12-2008, 11:59 PM
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RE: Circa 1982 O.S. VF .46
Bob, congrats on getting the VF going!
I am surprised that the mousse can is costing so many rpm - I would have expected it to be in the same ballpark as the open header. I'd try a few more props like the 11 x 6 or the 10 x 8 and see if that rpm difference is only a feature when running lighter props.
The Macs pipe, properly tuned, will make a big difference. My engine really runs well with the .60 pipe.
One thing that may be an issue for you is fuel economy. Mine really drinks it like there's no tomorrow with the Macs pipe fitted.
I am surprised that the mousse can is costing so many rpm - I would have expected it to be in the same ballpark as the open header. I'd try a few more props like the 11 x 6 or the 10 x 8 and see if that rpm difference is only a feature when running lighter props.
The Macs pipe, properly tuned, will make a big difference. My engine really runs well with the .60 pipe.
One thing that may be an issue for you is fuel economy. Mine really drinks it like there's no tomorrow with the Macs pipe fitted.
08-14-2008, 04:40 PM
#6
RE: Circa 1982 O.S. VF .46
Harry,
Thanks for the encouragement regarding the VF. It truely is a wonderful little engine.
I found and reread the instructions for the "Magic Muffer" (the mousse can pipe of the 80's) and found that my header was about 2 cm too long. Trimming that put well over 1000 rpm back into the system, so I am headed in the right direction. Since the flying site is 10 C warmer than my original test site, as well as 200 meters or so higher, I figure I'm now pretty close to getting the same rpm on the pipe as with the open exhaust (plus the magic muffer is one heck of a lot quieter). Since I'm going to play around a bit with props, I'll probably leave it a bit long for now.
I put on a Master Airscrew 10 x 8 and it turned about 13,400 rpm. That prop really unloaded in the air and was probably well over 14k when flying. Needless to say, mounted on a Hobby People "Mach Racer" I'm starting to get to some respectable air speeds. With the engine "unloading" that much, how rich does it need to be on the ground to get max turns in the air? Even if I leave it only about 500 rpm rich for takeoff it takes very careful throttle management to get it off the ground without stalling the engine.
You mention that you are using the .60 sized MAC's Pipe on your VF. How long is your header with that combination? Is there an advantage to having the 60 sized pipe over the .45 sized pipe?
Regards,
Bob
Thanks for the encouragement regarding the VF. It truely is a wonderful little engine.
I found and reread the instructions for the "Magic Muffer" (the mousse can pipe of the 80's) and found that my header was about 2 cm too long. Trimming that put well over 1000 rpm back into the system, so I am headed in the right direction. Since the flying site is 10 C warmer than my original test site, as well as 200 meters or so higher, I figure I'm now pretty close to getting the same rpm on the pipe as with the open exhaust (plus the magic muffer is one heck of a lot quieter). Since I'm going to play around a bit with props, I'll probably leave it a bit long for now.
I put on a Master Airscrew 10 x 8 and it turned about 13,400 rpm. That prop really unloaded in the air and was probably well over 14k when flying. Needless to say, mounted on a Hobby People "Mach Racer" I'm starting to get to some respectable air speeds. With the engine "unloading" that much, how rich does it need to be on the ground to get max turns in the air? Even if I leave it only about 500 rpm rich for takeoff it takes very careful throttle management to get it off the ground without stalling the engine.
You mention that you are using the .60 sized MAC's Pipe on your VF. How long is your header with that combination? Is there an advantage to having the 60 sized pipe over the .45 sized pipe?
Regards,
Bob
11-08-2009, 10:49 PM
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RE: Circa 1982 O.S. VF .46
Gents,
Ijust picked up a plane today and amimpressed to read up that the engine is actually the OS .46 VF. Looking at the setup, the original owner had an 11x8 prop on this. I don't know what fuel he ran thru this engine, but the compression is still excellent. Any guess what RPM I should be getting with the 11x8 with the pipe? I'll put some Morgan’s %15 thru in during the next few days and see what I can come up with. The owner said this plane only goes about 80MPH. The plane seems a bit big and heavy for a .46, but we'll see.
11-10-2009, 11:06 AM
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RE: Circa 1982 O.S. VF .46
FYI,
I tested the engine with the APC 11x8 and it felt like it was lagging. With a tach and a Scimitar MA 11x7 she got up to 13,500... Only thing weird is the engine will cut outfor no appearant reason when left between idle and mid throttle for a few minutes. I'm suspecting a glo plug, but I'm also not too experienced with the TunedPipeand maybe it needs some adjustments on the low end? I'm going to pick up a 10x8 today and take it to the field with me next time I'm out and see if there's a difference with the 11x7.This should be a fun plane...Unbelieveable that an 30 year old engine can run so good. Who would have figured?
pg
