With the rule change for 2610 allowing up to .30 engines, is it unreasonable to allow them in 2548? With the RPM limits in place, I don't think it's going to accomplish much, and it will allow the use of cheaper engines like the Magnum and Thunder Tiger .28's. $15 per engine may not sound like much savings over a .25FX, but considering most people have 3-4 engines, the savings could equal having an additonal one available for the same money.
Just a thought.
.30 engines in 2548
Moderator: hbartel
-
Ed Kettler
- Posts: 3437
- Joined: Sat Dec 15, 2001 6:05 pm
- Location: USA
- Contact:
Did the 2610 change get approved?? I have seen nothing on it.
I pulled the 2548 proposal as I could get no consensus on what it should be (no change, .28, .29 or .30). Then I asked if anyone out there would like to pick up the ball and run with it. No response.
So as far as I'm concerned it's dead unless someone wants to resubmit one.
Mine as written is in the members Only Forum. Feel free to copy and modify the text if you want to submit it.
-----------------------------------------------------------------------------------------------------
Edit 8/25/08. Now the 2610 change (engines up to .30) is confirmed and made public I am surprised there are no takers on this proposal.
Once again, I tried and am not going down that road again, but anyone who wants to pursue this is more than welcome to lift my proposal from the MOF, change the proposer name to theirs, and submit it.
If that doesn't happen then I guess it's no big deal. (Or nobody cares[?])
I pulled the 2548 proposal as I could get no consensus on what it should be (no change, .28, .29 or .30). Then I asked if anyone out there would like to pick up the ball and run with it. No response.
So as far as I'm concerned it's dead unless someone wants to resubmit one.
Mine as written is in the members Only Forum. Feel free to copy and modify the text if you want to submit it.
-----------------------------------------------------------------------------------------------------
Edit 8/25/08. Now the 2610 change (engines up to .30) is confirmed and made public I am surprised there are no takers on this proposal.
Once again, I tried and am not going down that road again, but anyone who wants to pursue this is more than welcome to lift my proposal from the MOF, change the proposer name to theirs, and submit it.
If that doesn't happen then I guess it's no big deal. (Or nobody cares[?])
I don't fly glow engines anymore, so it's no REAL concern of mine...I was only thinking for the people that do, the way the price of OS engines through Tower are skyrocketing, that opening it up to less expensive (at this point, $30 per engine less!)options would be acceptable. Considering there is an RPM limit, regardless of which engine you use, you're going to belimited to the same performance level. With 2610 allowing them, and Limited B set with a .29 limit, I can't see why using the Mag or TT .28 wouldn't be allowable, even desirable.
Apparently the consensus I gathered is that the Magnums are designed to unload more in the air, thereby giving them a performance edge over the 25FX. Like I said, it's no concern to me, I'm flying $25 electric motors, but with the state of rules in other classes, I think it's a litle odd that you could fly a .28 in 2610, or Open B, or Limited B, but not in 2548.
Anyone interested should take this to the rules discussion area. I would support it if someone chose to champion it.
Apparently the consensus I gathered is that the Magnums are designed to unload more in the air, thereby giving them a performance edge over the 25FX. Like I said, it's no concern to me, I'm flying $25 electric motors, but with the state of rules in other classes, I think it's a litle odd that you could fly a .28 in 2610, or Open B, or Limited B, but not in 2548.
Anyone interested should take this to the rules discussion area. I would support it if someone chose to champion it.
I would agree, the os 25 fx shot up to 95 bucks, 25 percent increase. Besides me, my two boys fly combat also, so the expence for me is triple, the fx is out of my price range unless I can find used ones. The magnums are still affordable. are they putting out the power the os is? I am new to this stuff so as far as proposing the change request, I wouldnt know what to do but I will back anybody who wants too
I bought one Magnums to experiment in open b. The FX well out performs the magnum. In limited b I could not get the magnum over 13,800 with the 10x4 prop and a very diminutive stock muffler. I think the motor size went the wrong way 2610 they should have come down to 25 based on the complaints of too much speed and too much carnage. MTCW the motor is not a good choice, though with some tinkering someone will get them to perform. I dont think cost is a good argument to fix a rule that is working pretty good. I can see the carage argument for the people that wanted to bring 2610 down to 25s. BTW I usually order my FX25s in lots of 3 and negotiate with the LHS who always gives me a pretty good price always better than TH.
Some magnums run better than others but overall they make a decent running engine and make good LimB engines due to the low rpm. On a MCP (and big carb, see below) they will actually out turn a 25FX but they tend to vibrate too much at that high rpm and durability suffers. At LimB rpm they seem plenty durable. Overall the FX is better in every way except for cost. There are some things to do to every magnum to improve reliability and performance.
PERFORMANCE
-it's been awhile since I opened up a new Magnum but they usually come with three head shims, a .004 and two .002. I remove all but one .002
-I've seen magnums with three different carb sizes, from about .236 up to about .280, with another one in between at around .260. obviously the bigger carb performs better and I don't know why Magnum supplies different ones, probably whatever they have laying around. the .236 is the same as the .25 (which is a weak engine) and the larger ones are probably from the .32 and .36. Most I've seen recently have the smaller carb.
-the machining isn't the best on the magnums and i look for casting flash on the muffler header and tailpipe, and machining burrs on the crank window that would restrict/disrupt airflow
-even at LimB rpm the magnum vibrates more than the FX so i strongly suggest blue loctite on the carb retaining bolts. Also remove the carb rotor screw and jam nut, degrease (I use spray brake cleaner) and reinstall with a little dab of blue loctite. Make sure no loctite gets on the tip or it will bind the carb rotor! Also make sure the jam nut is snug!!! If it loosens, the vibration will wipe out the threads in the soft carb body and the carb will be junk. The nut is a challenge to tighten, I have a flat 5mm wrench from an OS fourstroke engine that works great for this nut.
-vibration will also make the low speed needle creep, this will give you fits if it decides to vibrate IN, shutting off the fuel flow and you can't figure out why the engine won't restart! a piece of large fuel tubing slipped over the throttle arm nut will grip the head of the low speed needle and help keep it from creeping.
-be sure to check torque on the head bolts, backplate bolts, and muffler bolts regularly, especially during breakin.
PERFORMANCE
-it's been awhile since I opened up a new Magnum but they usually come with three head shims, a .004 and two .002. I remove all but one .002
-I've seen magnums with three different carb sizes, from about .236 up to about .280, with another one in between at around .260. obviously the bigger carb performs better and I don't know why Magnum supplies different ones, probably whatever they have laying around. the .236 is the same as the .25 (which is a weak engine) and the larger ones are probably from the .32 and .36. Most I've seen recently have the smaller carb.
-the machining isn't the best on the magnums and i look for casting flash on the muffler header and tailpipe, and machining burrs on the crank window that would restrict/disrupt airflow
-even at LimB rpm the magnum vibrates more than the FX so i strongly suggest blue loctite on the carb retaining bolts. Also remove the carb rotor screw and jam nut, degrease (I use spray brake cleaner) and reinstall with a little dab of blue loctite. Make sure no loctite gets on the tip or it will bind the carb rotor! Also make sure the jam nut is snug!!! If it loosens, the vibration will wipe out the threads in the soft carb body and the carb will be junk. The nut is a challenge to tighten, I have a flat 5mm wrench from an OS fourstroke engine that works great for this nut.
-vibration will also make the low speed needle creep, this will give you fits if it decides to vibrate IN, shutting off the fuel flow and you can't figure out why the engine won't restart! a piece of large fuel tubing slipped over the throttle arm nut will grip the head of the low speed needle and help keep it from creeping.
-be sure to check torque on the head bolts, backplate bolts, and muffler bolts regularly, especially during breakin.
no experience with the TT 28 but it looks like a lo-po sport engine. I've never run a GMS 25. Several years ago when the Canadians flew with us, a lot of them ran the GMS because in Canada they were WAY cheaper than an FX. The occasional GMS ran strong but mostly they were infernally unreliable and gave them fits. The general impression was that they were not satisfied with them, so I never tried one. That was a while ago, maybe GMS made improvements.
The TT PRO25 is no longer available, I think, but it was a dog. I've run several and tried playing with head spacing, carefully deburring everyting, larger carbs, etc and they still put out modest power. Decent running engines, but not powerful enough for combat. I've got one I'm still fiddling with but so far no dice, mid to high 13k at best on 10x4.
The mag 28 is a decent engine and you can certainly have some fun with it in combat. the 25FX is just a bolt in, plug and play engine for 2548 or LimB and is hard to beat, but it is a bit pricey, even more so recently
The TT PRO25 is no longer available, I think, but it was a dog. I've run several and tried playing with head spacing, carefully deburring everyting, larger carbs, etc and they still put out modest power. Decent running engines, but not powerful enough for combat. I've got one I'm still fiddling with but so far no dice, mid to high 13k at best on 10x4.
The mag 28 is a decent engine and you can certainly have some fun with it in combat. the 25FX is just a bolt in, plug and play engine for 2548 or LimB and is hard to beat, but it is a bit pricey, even more so recently
Scott I knew someone had to have tinkered with the magnum. I am hoping to try some of your suggestions and I'll get back with you. some of my first FXs for open b that I have been beating on for 2.5 years are starting to let loose I broke a rod 2 weeks ago. Do you do anything to overcome the small muffler (on the Magnum). Is it "legal" to use a larger GMS or OS muffler on a magnum motor? (I dont even know if it would fit I am just throwing a what if ouit there)
it's fine to exchange mufflers. I have not noticed that the small magnum muffler affects performance, haven't really done a detailed study swapping mufflers to see if it helps. You could try a .32 size muffler which has a center section that adds more volume, or try the 25FX or GMS mufflers. I tried OS32/40FP mufflers on my FXs which have a bit larget volume but they did not seem to improve rpm noticeably.
Is this a dead horse or is there any interest in this. I am looking at getting some new gear soon(christmas) and would hate to get new engines for some of the combat fleet, only to be surprised by a rule change that allows a bigger engine.The same prop at the same rpm levels the field with electrics,so what would be the problem with a .28 or .30 swinging that 10x4 master airscrew?