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Engine basics => Engine set up tips => Topic started by: 50+AirYears on March 19, 2011, 12:08:50 AM
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A few years ago I picked up a cookie tin of engines and parts from an estate sale. Among the parts was a CL venturi for the Fox .45 through maybe .50 or .60. Since I have a couple of the .45 rc engines sitting around unused, I was thinking on making the conversion, possibly for an NIB Shark .45 I have. Any suggestions? I was thinking for CL, maybe a 12-6 or 13-5 prop. All the ones I have generaly start in one or two flips by hand, run well over 14600 and idle under 2000 on 10%, extra castor, and an APC 10-6.
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Hi 50, The big case Fox .45 is a real power house and can be used for CL satisfactorly. Keep in mind that it is not a 4-2 engine and run it with low pitch and you will find it does a good job. You can add a head shim or two to tame it a little. When that engine was introduced, Duke Fox was aiming his products at FAI and most every thing was over compressed. I run mine on FAI fuel and with one additional head shim and they do just fine. Prop it with a 12 x 4 to start with and work from there to get the lap times that you want. Phil
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Thanks. I kind of though so, I've always thought they were a kind of gentle giant. I've never had any trouble with them in RC, except maybe for finding a cast engine mount. That case seems wider than even some .60s, but they do take a beating. Mine, and another RC club membe, have actually had the engines imbed themselve in tree trunks, and the only damage besides broken plane and prop, is broken needles and maybe a distorted collet cone.
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HI Tony,
Like Brother Phil said, they will work fine, stock, as long as you don't expect a 4-2 run. A lot of good engines came out at a time when stunt was still being ruled by the "Classic 4-2 style" enginew run, so they were cast aside when they wouldn't do that.
There are plenty of great engine guys who can get the 4-2 run out of them, and usually with plenty of power left for our purposes. But a "low" pitch prop, and a soft 2 stroke needle setting will work in most all cases. Some better than others, but all fine for "Sunday" flying.
Big Bear
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I had a big case .40 until the post office lost it. I put it on a 35 year old Twister and it "Took off like a rocket". I've been running a stunt tuned modern 46 ABC BB and it runs wonderfully. It pulled a 61 oz. kit bashed Pathfinder with 710 squares around like nothing in a fast 4 cycle. I love them. I've since obtained an old large case .40 but have nothing in which to put it. I also have an old case .45 but have done nothin but broken it in, so can't speak to that.
Bob