stunthanger.com
Engine basics => Engine set up tips => Topic started by: Chris Fretz on May 23, 2016, 07:16:20 PM
-
Could you guys educate me on what kind of OS 25 this is? Do you run it like a LA25 (prop,rpm,fuel)?
-
.25 FSR?
-
.25 FSR?
You may be on to something there!
-
dual ball bearing engine, will produce a huge amount more power
Randy
-
Could you guys educate me on what kind of OS 25 this is? Do you run it like a LA25 (prop,rpm,fuel)?
I think it's a 25SF. A lot more power than a 25LA in general. I wouldn't expect to be able to keep the airplane below the sound barrier with any commonly available props with a stock 25LA venturi. Maybe something like a really light 11-4 and a smaller venturi, but I doubt it would have the kind of maneuvering response you get with the 25LA.
It could probably work nicely piped and I recall Darrell Harvin with a very similar setup back in the early 90's (maybe a 32 instead of a 25).
Brett
-
dual ball bearing engine, will produce a huge amount more power
Randy
Thanks Randy
-
I think it's a 25SF. A lot more power than a 25LA in general. I wouldn't expect to be able to keep the airplane below the sound barrier with any commonly available props with a stock 25LA venturi. Maybe something like a really light 11-4 and a smaller venturi, but I doubt it would have the kind of maneuvering response you get with the 25LA.
It could probably work nicely piped and I recall Darrell Harvin with a very similar setup back in the early 90's (maybe a 32 instead of a 25).
Brett
Doesn't sound like this engine is going to do much for me then...
-
Build any good combat ship ...easy fasted way is a Phil Cartier Core House fast combat plane like the GOTCHA STREAK III and stick that sucker on with a 8x8 prop, bladder fed, 15%N 20%oil 50/50 ad hold on! ...loose the muffler
Put it on the nose of a Core House Rugged Stunt trainer with a thin low pitch prop 10x3 add some tail weight
-
Doesn't sound like this engine is going to do much for me then...
Need a bigger airplane than a Tomahawk, that's for sure. Fred's suggestion is a good one.
Brett
-
Thanks Randy
GOOD Nobler motor, use a 10 x 4 pro Z or similar
-
I think the 25 SF cases were identified with "SF" as part of the casting.
Either one, FSR or SF, is a screamer.........
-
Thanks for the info fellas.
-
Is a 25FX in the same boat as this engine?
-
It is FSR25. I have run mine with almost the same setup as FP/LA25s for Doodlebug.
6.8mm venturi with 4.0mm NVA, less restrictive muffler, APC 9.5 X 4 (cut 10-4) and 10% nitro 23% all syn fuel. I felt it had a little more power than FP/LA. It can be opened the venturi a little to get more power with steady run but need a larger tank.
Aki
-
yea , FSR definately . used a clone ( Magnum 25 pro ) lots in a Nobler Sized thing .
9x6 or 10 x 6 worn to 9 1/2 , trike gear so the grass ronded the tips le nicely after
Id tried a few touch & Goes up the resivoir on the concrette in the wind .Impossable
to touch but was a bit of force in the wind .Tornado Props , the flexi 10 x 6 it bogged
a bit till it wore down .dunno if it was a black 9 x 6 or 9 x 4 for a blow , likely both ,
at times .
(http://stunthanger.com/smf/index.php?action=dlattach;topic=41658.0;attach=250095;image)
21/35 in it there , but mustve gone over 10 gallons thru the .25 in it . 52 span & 45 + Oz.
a quick wipe with a rag & petrol took a hour and a half , at one stage - when it'd got a bit
gooked up . Mine had a Fox bb 119/25 CL intake, so the needle was level with the outside of the fuel tank .
Got it rich down low & lean up the top of the circle . A bit gutless for it but kept you on your toes .
Magnums identical internally .
about OS 35 S performance .
used 55 ft. of .018 when it was blowing , but ive had that motor on 70 ft of 016 solids and it cruised along ok with a big sag in the lines ,
still drag itself over the top of the circle etc .
A Don Still Stuka would be ideal for it .