GP Shoestring ARF Engine?
 

I just ordered a Shoestring and am eagerly anticipating its arrival. In the meantime I have been researching engines to put into this beauty and think I have it narrowed down to a 4 stroke. (Read below, this has now turned into needing a 2 stroke due to monitary concerns) The only thing is, I don't want to cut the cowl.

This is my second plane and I'll be buddy-cording it for a while until I am comfortable enough with it. Can't wait to see it!

Dayton

RE: GP Shoestring ARF Engine?
 

Only engine i know that would fit side mount is a ys 63.But you can mount a 91 to 110 inverted looks good like that.

RE: GP Shoestring ARF Engine?
 

I have a G90 sideways in minewith a 13/8 apc prop. Very fast combination. Note I kept the cowl cutting down to a minumum. Friend of mine has the same plane with an inverted Saito 100. That would be my recommendation for you. I usually make low approaches which helps slow it down.

RE: GP Shoestring ARF Engine?
 

I have a YS .91 AC mounted inverted. Keep in mind that a heavy engine will require lots of tailweight to balance as I found out with the YS. This combo is fast though, with a 14X10 apc it goes. Mine flies like it were on rails, but does not slow easily, I have to make a long aproach on landing. A friend powered his with a .61FX with a 12X6 prop and did not have this problem.

RE: GP Shoestring ARF Engine?
 

I have a OS 91 Surpass 2 mounted inverted and it looks and flys great!!!!!

RE: GP Shoestring ARF Engine?
 

I am imagining a YS110 turning an APC 14x12 or 15x10. :D

RE: GP Shoestring ARF Engine?
 

Very good imagination!:D

RE: GP Shoestring ARF Engine?
 

Back to the drawing board...

Due to budget constraints (read wife), it looks like I'm going to need to put a two stroke engine in this plane. I'm considering the Tower Hobby .75 with a pitts muffler. Does anyone have any other suggestions or experience with the Tower Hobby engine?

Thanks!

Dayton

RE: GP Shoestring ARF Engine?
 

Byzandula - Looking at the weight and price difference why not go for a 90 sized 2C like the G90?

Snoop - I got the YS but not the Shoestring, way to expensive in Malaysia, its controlled by the LHS in Singapore. Costs about USD390 here! I love the way it looks, the rear of the fuse with stringers but just waaaaaay outta whack in terms of the price.

RE: GP Shoestring ARF Engine?
 

I am concerned that I would have to cut the cowl with the G-90 as others have suggested that was the case in other threads. I really want to preserve as much of the cowl as possible. Does anyone know if the Tower Hobby engine will mount well without a cowl massacre?
As for the weights (according to Tower Hobbies):
The Tower Hobby .75 is:
Weight: 652g (23.0 oz) (with Muffler)
Weight: 535g (18.9 oz) (without Muffler)

and G-90

Weight w/o muffler: 589g (20.66oz)
Weight with muffler: 765g (27oz)

RE: GP Shoestring ARF Engine?
 

I have a magnum 61 in mine, fits in the cowl and it flies nice. The magnum 91 is the same external size and is on sale for 119.99$ at hobby people. I would get the Mag .91. I'm not sure about the tower but it is about the same size as the Magnum.
I recently picked up a SK .80 from kangke for 70$ and i'll probably replace the Mag .61 with the SK .80(alot more power). ;)

RE: GP Shoestring ARF Engine?
 

Byzandula, I did not want to cut up that neat cowl either, did some research and determined that all 90 2 stroke engines require cutting the cowl. Decided on the Tower .75 which does fit horizontally without cutting. Am using a Bisson pitts muffler which puts out a throaty sound , and supplies good pressure to the engine. I beefed up the Shoe with 1/4" spruce stringers on the fuse, epoxied the firewall and landing gear plate etc. Plane with all mods comes in at exactly 8 pounds. Have about 50 flights and am very pleased with this combo, the Tower has been rock solid, and no overheating problems in the fully enclosed cowl. I was primarily interested in the aesthetics of the plane, and did not intend to race it, but just for kicks, we radared it a couple of times and saw 98- 106 mph range, depending on wind conditions. This was my first Tower engine, bought it as a first choice, and have been very impressed with it so far, great value, go for it! Hope this helps.

RE: GP Shoestring ARF Engine?
 

Garch 22,

Thanks for the info. I am definitely leaning toward the TH .75 right now with the bisson pitts muffler, although a couple of the guys that I fly with are telling me to bite the bullet and buy a 4-stroke. How is the vertical performance of the plane with the TH .75?

Byzandula

RE: GP Shoestring ARF Engine?
 

You can cut the cowl without drawing attention to it. Enlarge my photo which is here on your thread and see what I did to allow the G90 to fit.

RE: GP Shoestring ARF Engine?
 

I have a TH 75 in my Stuka and I like it a lot! The engine is very tight from the factory. You need to heat up the the top part of the engine with a heat gun so you can turn it over to start it the first time. After that its easier to turn over and after a few runs its fine. Very strong engine and fairly easy to adjust the carb. There were some comments at the field from other flyers about how a Th engine would probably run like crap. After they watched it haul the Stuka screaming around the field they were impressed and changed their tune![8D]

RE: GP Shoestring ARF Engine?
 

Byzandula, I have been using a 12x8 APC mostly for speed runs, and a 13x6 APC for sport flying. If you want to go vertical I would try a 13x5. The Tower gets it best power by revving up. Mine will go vertical till I cant see it.

My Hanger:
GP Ultrasport 60 w/ OS 90 FS Surpass ll Pumper, Mistress Pattern Plane w/ YS 60 RE on Tuned Pipe, VectorFlight 66in Extra w/ Magnum 91 xls
GP Viper 428 pylon racer with Nelson 40, GP Shoestring w/ Tower .75, 70in. Sig Citabria W/ OS .70 Surpass on Sea Commander Floats
Kangke SK-50 w/Magnum .52 xls Scratch built 40 in. Shoestring w/ Aveox 010 Brushless motor, Crazy Sparrow w/ Astro 05 Brushless

About 20 gliders including 4-meter ASW-20, Kit Built Bird of Time, 3-meter DG 600, Swift 2-meter scale Aerobatic, Sig Ninja, Hobie Hawk, old Bob
Martin Coyote, Paragon thermal duration, Ben Buckle 60 in. Scorpion Old Timer w/ OS 40 Four Stroke

Glaser Dirks DG- 202 17-meter : Flaps, water bags, oxygen, computer/nav. 48:1 glide ratio 2000 hrs PIC

RE: GP Shoestring ARF Engine?
 

garch 22 and everyone else,

Thanks for the info. I have ordered a .75 Tower Hobby engine with Bison Pitts muffler. I went with a 13x6 prop for breaking in and sport flying. I'll have to play with others after I break the engine in. Looking forward to getting this one finished and airborn this season! I can't wait!

Byzandula

RE: GP Shoestring ARF Engine?
 

I went with a OS 91FX with a tuned pipe on my Shoestring. And BTW this motor has been nothing but reliable and good to me. I didnt have to cut the cowl out for the engine at all it fits perfectly in there. Now the tuned pipe was another story... I had to run it out the side and mount it to the landing gear. That part was a little tricky. I would really like to run it under the belly of the plane for better areodynamics, but with the belly i just dont know how im gonna manage that. But man this thing REALLY gets down!! Im running a 12X8 APC prop and spinning 13,200RPM on the ground. I havent done much pipe tunning, so i expect i could get some more RPM out of it by shortening the pipe a tad. I make sure not to make any fast hard banking turns while at full speed, due to the scare of folding the wing up :) This plane is my favorite plane in my fleet. It basically needs no runway and vertical is unreal! It will go up and out of your site if u let it. It never stops![>:] Deffinatly the fastest 1/4 scale plane at my field :D