0_CoooL

I am thinking of buying a New Phoenix SU-31 Sukhoi from Tower in the next few days! I am trying to figure out which engine to use on the nose! I would like to get alot of Vertical if at all possible! I have in mind a Magnum .52 Four Stroker, But if anyone knows if this engine is not that wonderful or a better engine in the same price range I would like to know about it!

Would the .52 4-Stroker be enough for this Su-31? Or shall I go with a .60 2-Stroker?

AtomHeartMother

My buddy has a Magnum 52 4 stroke. Not a bad little motor and very quiet, but the Suk will be way underpowered with it. You want a strong .46 2 stroke at least. I have an Irvine .53 in mine and do not have unlimited vertical though performance is very strong. A .60 2 stroke would fit the bill or maybe a saito .72 or .80 if you want the 4 stroke sound.

Dewey2

My Feedback: (24)

Mmm the Magnum 61 would be better, or the new OS70 would be best in that price range.

roltech

We had a member of or club that had one and said that this plane was tail heavy he had a 60 size 4s but still had to add weight to the nose, he recommended to go to a larger motor, to add weight. I have a phoenix Sukhoi SU 31 46 ARF, still need a motor and still in the box. from what I understand it depends where it was made.

roltech

vx570

Have this plane and it is heavy, believe me a Magnum 52 4 would be a very under powered unit for it, a Magnum 60 4 would be much better and at not a great deal more expensive, the Thunder Tiger 61 2 stroke is a good price and would be great, have a MDS 58 in mine and its terrific.

Cheers Greg

PE2fan

My Feedback: (8)

I have a Saito .82 in mine. Only 2 flights so far so not much info. Came out nose heavy had to add 3oz of lead in tail. I did mount the engine 1/4" too far out though. Not sure how much that matters.

Oh and just to remind everyone. Make sure your flaps are dialed in to 0. I didn't check this and nearly lost it. One porpoising mutha with flaps down.

Mine slows down well without the flaps.

0_CoooL

Thanx for all the info, After looking at the .52FS I agree with the Under-Power said above! I am just going to stick with a 2-Stroke like a TT Pro .46 or something alond those lines!

[:-]

da Rock

mdlnewman,
Nose heavy? Mine too and with an OS46ax on it.
It appears that Phoenix installed some lead behind the firewall on that model. At least a number of people have mentioned finding it on their Sukhois. If yours has it, removal of it would undoubtedly let you pull that tail weight too.

JRC

My Feedback: (1)

Here is an image of the lead weight added in the nose of Phoenix Models Su-31 at the factory

davidm

My Feedback: (18)

MY Sukhoi does not have the lead weight installed, mine is almost 2 years old.
I have a TT46 and placed the battery above the tank. Without additional weight.

David

vtx1800

No lead in mine either, but it is 2 years old as well. Mine performed well with a YS.63 and a 12/6 apc.

roltech

Funny reading this thread, must be a different Sukhoi but the one sold around hear last summer needed lead at the nose as it was tail heavy, that's why he recommended to install a 60 or 70 size motor.

roltech

Shok

My Feedback: (28)

I have flown this plane many times with a saito 50 sized four stroke and it flys just fine.
Will not have unlimited hover but is no slouch either.
No lead needed either.

da Rock

chuckle... The local hobby shop had to special order mine about a month back and seemed to be unfamiliar with it. And when it came in they were somewhat startled at how good it looked for the price and that it had the surfaces already hinged etc etc. So they decided to order a couple more. And those were sold in about 2 days. So they ordered a couple more. And they sold right away.

Today I swung by the hobby shop to pick up some servos for my Ultimate on the way to the flying field (to get in a couple more trimming flights on my Sukhoi) and they had two more sitting on the floor. They don't even put 'em up on the wall 'cause they say they aren't up there long enough to make it worth dragging out the ladder. And turns out that they found out about the weight right after they sold me mine. And told everyone that bought one. lol....

Mine flew great today. I've been able to idle the .46ax lower and lower every time out and it's impressed the devil out of me the last two flying days. The old eyes aren't what they used to be and pointing the nose up on that bird turns it into a dot real quick. Mine came out right around 6.5 lbs and I was worried that the engine might be marginal or it'd not be able to fly slow enough to land easily but..... I shouldn't have worried. My last landing of the day was in calm and it scared one of the field experts who came running out to warn me I was way too slow on approach. Truth is, I'd gotten it to mush into a stall a couple of times up high (when he wasn't watching) and I was pretty sure the sucker could come in even slower. I'm not a fan of stalling on approach when there's no recovery altitude. And the sucker promises to be real decent, so I wasn't even crowding my own comfort level. I think the sucker is going to be a favorite. I've already been offered $200.

Oh btw, when I first flew it and thought it was faster than I wanted and I wasn't running the idle very slow, I slowed it down by "carving" it a special prop. Took a 12-5W and trimmed the diameter some and took a bit of chord off. Darn, I wish wood 10.5-5 props were in piles in the LHS. Heck, there aren't any 11-5 props anywhere around here and I got the last 12-5s from the one shop that had some dusty ones.

Al Lewis

I just flew mine today with the Super Tigre .45 ABC, Pitts muffler, and a 12X5 prop and it has unlimited vertical. I built the plane with an 11X6 but way too fast! I'm actually going to a 12X4 prop to try and slow it down a little. VERY fast plane. This is my third and I flew my first with a Magnum .52 and it flew good but not like this. If you check it out I did a full user review on this plane.

0_CoooL

Lou, Your model looks nice! How does this model Track or Land?

da Rock

Lou55,
It's interesting how much difference there is between your cowl opening and the one that came on mine. Yours is much more open than mine. Btw, my entire cowl also came from the factory misshaped. It was egg shaped when viewed from the front, a little of which still is visible in the attached photo. I got most of it out with the foam "plates" I glued in, but the front area still held some of the warping.

da Rock

CosmicWind asked, I'm still trimming mine but it's very neutral flying. It's fairly heavy for a .46 size a/c so it's not buffeted out of it's chosen track by wind gusts as much as lighter a/c. And it really tracks where you point it. It holds it's roll axis very solidly. Four point rolls are pretty easy to do. I was up the last time out with a couple of 33% stunters and someone commented that the .46 Sukhoi was as smooth as the big ones. And I thought the same thing. I think it's the weight that does that. And the OS.46 hauls the weight with no sweat, so.... chuckle chuckle

Mine lands at any speed you'd want. My post above describes one of them. But I haven't flown mine enough to really suggest that mine is a floater, because it's not a light a/c. However, it will slow a lot. At least with my reworked prop it will. Haven't bumped the envelope with this a/c with a stock prop on it.

I know you asked the question to Lou55, but I figured you might like other observations as well. And I'm guessing that Lou answered that question in his review and since I didn't see it, I'm going there now.

0_CoooL

Thanks for the information on your Sukhoi DAROCK....... [8D]