was wondering if anyone knows of agood way to speed up my alpha trainer with out replacing the motor it is an evolution .46 motor. i ma running 15 nitro 18% oil any rec amendations oh how to speed it up maybe 20% nitro i am not sure. i dont want it super fast. but just a little bit faster.

lose the 3blade prop. Go with a 10x8 or 11x7

The theory is that you want to go with the biggest pitch prop that you can find.... without overloading your engine. Reduce the diameter of the prop to compensate for increased pitch.

Pitch is the theoretcal distance the prop will travel forward with one complete revolution. A 10x7 prop will go forward 7 inches with one revolution. It will spin faster than an 11x7 because it is smaller, thus a 10x7 prop will give a better top speed than an 11x7 (and it will spin a lot faster). A 10x8 will make your plane faster than a 10x7, and so on.

With the increas in speed, your plane gets a correlated reduction in "power". The pitch and diameter of the prop can be thought of like gears on a bicycle. A 10x5 prop is like 1st gear, and can really pull your plane strongly, but will not get to a very high speed. A 10x10 prop would be like the top gear, it will make your plane scream, but probably will not be able to get the plane airborne from the ground because it does not produce the right thrust at low speeds.

If you really want speed, go with the 10x8 over the 11x7. Experiment by increasing the pitch some more if you want.

Experiment with different prop brands as well. I have found that APC props give me better performance than Master Airscrew....

gus

A 10x7 APC on that engine will make the Alpha go plenty fast. I have a couple of students who have done that, and it really wakes the plane up. The 3-blade prop it comes with is designed to slow the plane down.

I use a 10x6 APC on mine and it pulls great on take off and flies plenty fast for me. I think a 10x7 as Montague said would probably work fine for you.

I've got one myself! Been told that if you take out the muffler baffle, switch to a 2 blade 10x6 or 11x5, and lose the flywheel it should scream. Now remember, if you take that flywheel off it is a significant CG change. It will move aft making the plane more unstable compared to what your used too. It will still be stable, but might float more on landings, drop a wing on stall, and be more "twitchy" on the elevator. Dont forget you'll have to get a new spinner too!! Hope this helps. I wll be looking forward to your flight report after the mods as I plan to do this soon!
Nik

If he's got the Evo .46, that's not the trainer model.

What size prop are you using?

thanks for the input guys. i am running a 10x6 2 blade prop right now. i am thinking of trying a 10x8 and seeing what that does also i am going to take out the baffle. will removing the baffle make the engine louder?? is there anything i should know about removing the baffle??

minnflyer my lhs said it was an evolution .46 motor in this plane am i wrong?
This is the actual motor i have. But it does not say the size of the motor
[link=http://horizon.hobbyshopnow.com/products/description.asp?prod=EVOE100]Evolution Trainer Power System [/link]

thanks for all the help guys

Ok, it IS the Trainer Power System. I reviewed this engine not long ago, and I was able to easily swing an 11x7. Try that or a 10x8 and see how it goes.

PS, yes, that is almost a .46 (.45+ anyway)

Not to be sarcastic here, I have an Alpha, and the Arrow ( semi-semetrical wing version) but-
To make the Alpha faster- put the engine in another plane.
Putting a high pitched prop on this plane is going to load down the engine more than make the plane go fast.- It's a TRAINER.
If you "scream the engine" it's just not going to go a lot faster-to draggy.
Yes removing the baffle, flywheel ect., will make it louder/rev higher, ect. but find a nice clean design to put that engine in when you are ready.

Jetts

Jetts, you're right, a trainer will only go so fast, but the alpha is actually one of the cleanest trainers out there, and it can get going at a decent clip a little work, espeically compared to an LT-40, for example.

One trick on the airframe that might help go a bit faster is to reflex the ailerons slightly and move the CG back a tad. I don't know if it would be noticeable though, as I haven't tried it on an Alpha.

Minn, you're right, I was assuming he had the Evo "trainer power system", since he also mentioned an Alpha airplane. Very few people realize there IS a difference between the Evo "TPS" and the Evo .46. I didn't know there was a difference until recently. The TPS is frequently called a .46, even though it's actually a .45, and not quite the same enigne.

What I want to know is, why did the Evo guys bother making a .45 and a .46 seperately? What are the differences between the TPS and the .46 besides the flywheel and a small amount of displacement? Are they ported differently? I assume they use the same stroke, with the .46 just being bored out a bit more, but I haven't actually looked that up.

A couple of guys at my field run a 10x6 on the Evo TPS, which I still think is too small a prop, and they could get better performance from an 11x6 or 11x5, but it does fly well on the 10x6 and it won't hurt the engine, of course.

Oh, removing the baffle will make the engine louder in two ways. First, you'll be making the muffler less effective, and second, the higher RPMS will mean more prop noise.

Yea, I don't know why they did that either.

Something else to keep in mind with Alphas:

Don't just tape the wings together- epoxy them if you're flying this plane faster than what it was designed for. Also, as a trainer, there isn't much you can say bad about the plane, but I've seen the insides of them more than once, and have rebuilt many of them for students, and you would be supprized as to the inconsistant quality in glue, parts fit, etc. With that in mind, if you fly this plane fast, don't be shocked if the wings tear off in a tight turn at speed. I've seen it happen more than once. Anyway, if you're at that stage in your flying, do yourself a favor and get a better built, faster plane. You'll be much happier in the long run.

ok guys i jsut flew my alpha without the baffle in the muffler and it definetly changed the sound. the speed was better too. the only thing i noticed was that the engine seemed to be hotter. dident have a temp gun so i am not sure what the temp difference is but it is definetly hotter

Probably running hotter because it is turning higher RPM's!!

Do you need to remove the flywheel from the Evolution PTS if you are going to use a 2 blade prop or does it make a difference?

Nope, you don't have to remove it. However, some brands of spinners won't work with the flywheel, so if you want to put a new spinner on there to match the 2-bladed prop, you'll need to either find a spinner with a flat backplate, or pull the flywheel.