Author Topic: OS 40 SF/S CL matched to Tutor II (Read 2694 times)

Ray · « **on:** March 21, 2008, 08:05:24 AM »

This is the choice that seems in the offing for this one when it reaches San Antonio, unless it is really porky and weighs more than 60 ounces. The OS Max is supposed to next best to NIB, with very little running time. Fuel consumption information is lacking, so a six ounce clunk may be the starting point. Aren't we looking at another definite single speed power plant here that needs low pitch propping, and quite high rpm operation?

Incidentally, he wants to see if using some older, "heavy type" Veco wheels may simplify the low wing, high vertical CG symptom's correction.

Leester · « **Reply #1 on:** March 22, 2008, 03:19:40 PM »

Ray: It comes with a 180cc clunk tank (6 oz).

dankar · « **Reply #2 on:** May 16, 2008, 03:34:32 AM »

I had a .40SF and .46 SF in Sig Magnum prepared by Tom Muggleton. Both had tons of power and very user friendly. One of the best OS ever made but did need rework. Tom I guess got burnt out on engine work as Frank Bowman. To bad as both knew their stuff. Stock SF is very prone to run away. Some may not agree but been there.
Dan

Ray · « **Reply #3 on:** May 16, 2008, 07:47:34 AM »

Well, he's looking at Tigre V-51 and V-60 options because of running into complaints about Tutor IIs weighing more than they ought to, and ays the Max 40 SF and V-51 are practically the same physical size, although the ST 51 weighs more.

Mike Spiess · « **Reply #4 on:** May 16, 2008, 07:53:05 AM »

I have a Fox 50 on a Tudor II and it's got more than enough power. I just have to get a good motor run haven't figured it out yet. It's supposed to be a Silver Fox modified I bought it used.

Balsa Butcher · « **Reply #5 on:** May 16, 2008, 09:06:19 AM »

This is anyone who has ran a stock 40 or 46 SF in anything

. I am running a 46SF in a 58 ounce, 56" span T-Bird style stunter. Plenty of power, smooth but it has been re-timed. They like smaller props (11") running higher RPM but re-worked will hold a nice 4/2/4. ST-60, too much vibration on that particular profile - see cartoon in first sentence. ST-51 may be the best option IMHO.

john e. holliday · « **Reply #6 on:** May 18, 2008, 08:24:16 AM »

Quote from: Mike Spiess on May 16, 2008, 07:53:05 AM

I have a Fox 50 on a Tudor II and it's got more than enough power. I just have to get a good motor run haven't figured it out yet. It's supposed to be a Silver Fox modified I bought it used.

Mike, if that really is a Silver Fox 40 you need to contact the man his self. Lew Woolard is the man and stands behind what he does. When I get back today I will try to locate his address as he will not participate on the forums anymore. DOC Holliday

Steve Helmick · « **Reply #7 on:** May 26, 2008, 05:28:20 PM »

A few years back, at Delta Park in P'land, I judged Scott Riese flying P.40 Stunt with Richard Entwhistle's stock Tutor II, .40LA-S. It had enough power. I'd suggest a .46LA, because it's easier to prop, a bit torquier, generally easier to deal with, and no doubt smoother running than a G.51.

Steve

Will Hinton · « **Reply #8 on:** June 09, 2008, 10:24:07 AM »

I'm running a stock LA46 with the exception of putting a ST 51 needle assembly in it and boring the venturi out to compensate (can you say "Then it ain't stock!"?) using a 12.5 three blade Bolley with 4.25 pitch and it's working great in my Tutor II I'm using 66 eye to eye lines, Tom Morris type, and flying around 5.5 second laps. 10% Rich's Brew with 22% lube at 50/50 blend. Good tension everywhere, can't tell you what my rpm is because my tack died and the new one wasn't here yet the last time the wind was under 147 mph! What in the world am I doing in northwest Ohio!?!??

Somebody PLEEEEEEEEASE turn the big fan off!
Will

Just One-eye · « **Reply #9 on:** July 02, 2008, 01:04:49 PM »

Quote from: Steve Helmick on May 26, 2008, 05:28:20 PM

A few years back, at Delta Park in P'land, I judged Scott Riese flying P.40 Stunt with Richard Entwhistle's stock Tutor II, .40LA-S. It had enough power. I'd suggest a .46LA, because it's easier to prop, a bit torquier, generally easier to deal with, and no doubt smoother running than a G.51. Steve

I've never owned a G51 engine, and did have in mind an OS Max 40 SF, but I'd used a V51 years ago, and liked it pretty well, so I now have a couple of those, c/o some eBay sellers, but for either of those (SF or V51), I have some misgivings about "soft" engine bearers and large voids between the doublers. It seems to me the V51s were somewhat vibration-prone compared to ABC / ABN engines.

I'm thinking I may scratchbuild a Mobest style replacement fuselage instead of using the one with the ARF. The years-delayed reorganization of the house is nearing completion at last, and I will soon have a space cleared off on a table to assemble an ARF Tutor II, and after that, who knows what next. I've about decided to discard the ARF's fuselage, or to at least graft onto the rear section, a properly vibration-resistant front end, to suit whatever I choose for power, such as one of the V-51 Tigres I recently acquired.

Any comments?

Steve Helmick · « **Reply #10 on:** July 15, 2008, 10:05:15 PM »

Sounds like a Government problem...whether to graft or not. I'm thinkin' that all new is better...

Steve

Leo Mehl · « **Reply #11 on:** July 29, 2008, 07:52:23 PM »

Quote from: Steve Helmick on May 26, 2008, 05:28:20 PM

A few years back, at Delta Park in P'land, I judged Scott Riese flying P.40 Stunt with Richard Entwhistle's stock Tutor II, .40LA-S. It had enough power. I'd suggest a .46LA, because it's easier to prop, a bit torquier, generally easier to deal with, and no doubt smoother running than a G.51. Steve

I agree with steve however the 51 will last longer and has ball bearings.

Just One-eye · « **Reply #12 on:** July 29, 2008, 09:51:41 PM »

Anyone wanta throw brickbats? The V51 "looks right" somehow, and the G51 looks like a cheaply cloned knockoff of something better. As already noted, I've never had any "G" model Tigres other than G21s, and the V60 I acquired while looking for a V51, is my first "60" in about 57 years or so, plus or minus a year. Mostly, I stuck with 25s, 35s, 36s, and 40s, with a very few 46s from a single maker -- Super Tigre (G21).

Leo Mehl · « **Reply #13 on:** July 30, 2008, 10:14:35 PM »

Quote from: Just One-eye on July 29, 2008, 09:51:41 PM

Anyone wanta throw brickbats? The V51 "looks right" somehow, and the G51 looks like a cheaply cloned knockoff of something better. As already noted, I've never had any "G" model Tigres other than G21s, and the V60 I acquired while looking for a V51, is my first "60" in about 57 years or so, plus or minus a year. Mostly, I stuck with 25s, 35s, 36s, and 40s, with a very few 46s from a single maker -- Super Tigre (G21).

I wonder how many people think looks of an engine has to do with anything? Performance is what counts but I guess some people are a little more fussy about looks than I am.

Andrew Hathaway · « **Reply #14 on:** August 01, 2008, 08:49:42 AM »

So the G51 looks cheaply cloned... I remember back in the early 90's when the G51 was still made in Italy, and the local hobby shop had the OS 46SF-S and the G51 in the display case. Both were big, serious, dedicated CL stunt engines. With price tags over $100 for either one. The G51 looked 'weird' and the OS looked 'right'. Through my normal process I managed to acquire one of each, and put them into various junk. The G51 ran great after switching from a Fox plug to a K&B plug, and got better with nearly every run. I can't remember it ever giving a bad run. The OS 46 SF-S NEVER gave a single good run. Now I've still got that SF-S, it's been reworked and runs a little better then it did, and I've got another new in the box that I've never run and will never bother to build a plane for. That first G51 met an untimely end, but I've got 6 more I've accumulated. It was a bargain at over $100, and it's a total steal at the current Tower price. Probably the best engine that no one seems to appreciate, whether it's because it looks different, or the jump from a 40/46 to the 51 scares people, or whatever, it doesn't get the attention it deserves. My only complaint is I don't like large planes or 6oz tanks.

Just One-eye · « **Reply #15 on:** August 01, 2008, 09:33:06 AM »

You had to be there. I resisted getting a first Fox 29/35 during the early 50s because the Torps just plain LOOKED BETTER, so much more more professionally finished. And before 1955 or so, I wanted to GO FAST, not slow (after that, I wanted separate engines for separate fast or slow planes -- Fox 29 in a stunter, Johnson 35 in a combat plane -- eventually 2-3 each similar to those, while still in my teens).

Anyway, searching for "51-size" engine deals on eBay, the G51s seemed pretty much nonexistent when I had the Tutor on its way and still expected to have the spring cleaning (call it the 2000 decade major dwelling overhaul) completed sooner than has proved possible.

Chucky · « **Reply #16 on:** August 01, 2008, 08:47:36 PM »

IMHO, the current, PRC ST G-51 is "the engine" for the Tutor II ARF -- a great value. Got one in mine and couldn't be happier. Run it box stock with Adamisin tube muffler, ASP 12.25x3.75 and PowerMaster GMA 5/22 fuel. Pulls the plane through the pattern with solid authority.

Just One-eye · « **Reply #17 on:** August 01, 2008, 10:32:23 PM »

I may acquire one of those yet, but I am now what my folks would have called "engine poor" already, with more than I could possibly match to airframes (and still have room to turn around in a small house) by a factor of ten-plus.

Mike Spiess · « **Reply #18 on:** August 02, 2008, 11:26:43 AM »

I have a Fox 50 in a Tudor and this package fly better than I do. I'm learning a lot and soon I should be flying the whole beginner pattern.

Just One-eye · « **Reply #19 on:** August 02, 2008, 12:46:51 PM »

Quote from: Mike Spiess on August 02, 2008, 11:26:43 AM

I have a Fox 50 in a Tudor and this package fly better than I do. I'm learning a lot and soon I should be flying the whole beginner pattern.

That's great. Glad to hear it. I kinda think that the beginner pattern may have come along after I learned the complete 1955 AMA pattern (more or less, perhaps not recognizable to anyone else yet), with my own first flapped model and the first of very many Fox engines, about 52 years ago.

Richard Entwhistle 823412 · « **Reply #20 on:** August 05, 2008, 09:16:44 PM »

I fly my Tutor II with a Tower 40 (Same as an OS 40FP). I have blocked the boost port with JB Weld like Neumann does and cleaned up the case and liner a bit. Using a APC 11x5 and 60 foot lines I can dial in lap times of 4.8 to 5.1 seconds in a nice rich two stroke. With the stock muffler and using pressure I get the full pattern plus 6 to 12 extra laps on 4 1/2 oz of 10/22 Powermaster depending on needle setting. We have nine Tutors in our club and the largest power is an OS 46 LA. They all fly great and in the hands of an expert some have pointed 540 or better. When out of state fliers come to Portland, OR (Rootbeard, etc.) we line them up with a Tutor to fly and shortly there after they are on the quest to get one of their own.
Unless you have a very limp ST 51 I feel anything more than an OS 46LA is way over kill.

Later
Richard

Leo Mehl · « **Reply #21 on:** August 12, 2008, 05:21:54 PM »

Quote from: Richard on August 05, 2008, 09:16:44 PM

I fly my Tutor II with a Tower 40 (Same as an OS 40FP). I have blocked the boost port with JB Weld like Neumann does and cleaned up the case and liner a bit. Using a APC 11x5 and 60 foot lines I can dial in lap times of 4.8 to 5.1 seconds in a nice rich two stroke. With the stock muffler and using pressure I get the full pattern plus 6 to 12 extra laps on 4 1/2 oz of 10/22 Powermaster depending on needle setting. We have nine Tutors in our club and the largest power is an OS 46 LA. They all fly great and in the hands of an expert some have pointed 540 or better. When out of state fliers come to Portland, OR (Rootbeard, etc.) we line them up with a Tutor to fly and shortly there after they are on the quest to get one of their own.
Unless you have a very limp ST 51 I feel anything more than an OS 46LA is way over kill.

Later
Richard

Richard is right but I do not agree about overkill. I guess i just like a lot of touque power that will pull it thru almost everything. We do have a lot of tuders at our field and agree that they are great flying planes. If ya get a chance build one a fly it with a good LA 46 and just have loads of fun.

Paul Taylor · « **Reply #22 on:** August 20, 2008, 07:04:27 PM »

Quote from: Richard on August 05, 2008, 09:16:44 PM

I fly my Tutor II with a Tower 40 (Same as an OS 40FP). I have blocked the boost port with JB Weld like Neumann does and cleaned up the case and liner a bit. Using a APC 11x5 and 60 foot lines I can dial in lap times of 4.8 to 5.1 seconds in a nice rich two stroke. With the stock muffler and using pressure I get the full pattern plus 6 to 12 extra laps on 4 1/2 oz of 10/22 Powermaster depending on needle setting. We have nine Tutors in our club and the largest power is an OS 46 LA. They all fly great and in the hands of an expert some have pointed 540 or better. When out of state fliers come to Portland, OR (Rootbeard, etc.) we line them up with a Tutor to fly and shortly there after they are on the quest to get one of their own.
Unless you have a very limp ST 51 I feel anything more than an OS 46LA is way over kill.

Later
Richard

Yup like Richard says..... I went on a quest and got my own. LA .46.

Bill Little · « **Reply #23 on:** August 26, 2008, 03:21:55 PM »

I love these discussions.

It's like anything else in life, some people like what some others don't..........

All my ST *G* 51s have been T&L ones. I could not ask for a better traditional stunt run unless we start talking about my PA 51 and 61s (and I even have a great Big Jim Hemi ST 60. For the money, a properly set up ST G51 is an awesome stunt engine for those not wishing to spend the dollars on the high end pieces. Randy Smith and Tom Lay are the two I would go to for the ST rework.

I have an LA 46 and have flown a few other people's planes with a 46LA. To say that the LA46 even comes close to the ST46 is ludicrous. So far, I have not found them to be stronger than a good old ST 46 when used for stunt! I will use mine, but on a smaller size ship where I would have probably used an FP 40....

Mongo