SeamusG

I'm finishing up the rebuild of an LT-40 tail dragger. I've used an Evolution 52 for power. I don't like the power delivery of the Evo. I've got a couple of Saito 91's. The 91 weighs in 2.3 oz heavier than the complete Evo. That's a wash if I pull the added front weight.

Anybody match the LT with the Saito?

TIA,

soarrich

My Feedback: (98)

I had a LT-40 that I had 14 different engines on, the two that flew it the best where the LA40 and a Saito 50. The plane is a great flying plane when NOT overpowered, if you overpower it it becomes just a good plane.

SeamusG

Em, gotta digest that.

My LT40 is just an OK plane with the Evo 52 - which will kick an OS46LA'x or OS46FX'x butt! Perhaps, just perhaps, I should consider downsizing to a nice trainer rather than something with an attitude.

Geez Rich - now ya went an did it - made me think ...

SeamusG

How long does it take to replace an Evo 52 with an OS46FX? 15 minutes. They share an identical footprint.

Why an OS46FX? I'm at 5900 feet elevation and that's what I have.

Btw Rich - what motor mount do you use that can accommodate all of your "stuff"? For 60/110 sizes I use a Hayes AS60 / AL60. Both share the same bolt pattern for the firewall. The AL can handle the OAL of 4-strokes while the AS works with 2-strokes. Just need two throttle linkages.

MajorTomski

I had a student with a 90 in a LT 40 and we're at 1200 feet. His flew just fine, esp the vertical departures after a touch and go.

soarrich

My Feedback: (98)

I mounted large aluminum "T" mounts, then mounted the engines to a ply plate, then attached that to the mount. The most powerful engine I had in it was a OS.60FX or FSR, I forget it was five years ago, probably the least powerful was a OS.30 or the Testers .40 21 series. The OS .30 needed a bump to get airborne of grass, but flew the plane OK. I didn't like the OS.60 or the Enya .80 4c the where way overpowered, they took off in 3 feet, but you had to fly them at 1/4 throttle. It flew well with a RCV.60, but that engine had the power of a .40, the thirst of a .60, the weight of a .90, and the cost of a 1.20, but a cool engine.

My favorite was the Saito .50, nice sound, perfect power for slow speed acrobatics which the LT-40 does great.

SeamusG

Thx Rich - appreciate your input.

Major - I'm not into near vertical take offs 'cause mine usually result in a vertical down line - I try for slow and controlled even with my Edge & ShowTime. I reserve my (sometimes) vertical up lines for my attempts at pattern maneuvers.

noveldoc

My Feedback: (2)

Agree a 50 sized 4 stroke will do fine in this plane. I fly my Kadet Senior on one and it is happy. No rocket like takeoffs and climbout but pretty decent.

I'd be concerned the 91 was a bit too stout. In my bigger Senior, I spend most of my flight at about 40% throttle.

Tom

Bruno Stachel

My Feedback: (4)

I really enjoyed flying a LT-40 with an OS 52. On calm days I could fly mostly with throttle and slight rudder inputs only. The weight and balance seemed perfect with that engine.

Nintendomaniac_00

A buddy of mine had a Saito 65 in his tail dragger LT 40 and it was a great combo. I think the 50 is a little light, weight as well as power. I had an LT 40 with a Magnum 65 2-stroke and it flew great with some reserve power... Either way, this is a great airplane and you will have a lot of fun with it. Regards, NM

jamesc43

My Feedback: (2)

There's a guy at our field (6200 ft) that uses his LT-40 as a platform to run in engines mostly he uses the OS FS-52 in the plane. It flys
fantastic and is not lacking for power.

SeamusG

I went with an OS 46 FX - still in its break in period. I appreciate all of your input. Just finished (re)covering the plane and its final assembly. Need only to set up static CG (linear and lateral) - then it's time to (re)maiden.

Again - thx.

SeamusG

Just wrapped up the (re)build. All up weight is 7 lb. 12.5 oz. The CG is at the midpoint of SIG specification. There is 5.5 oz of lead, 2 NiMH batteries (4.4 oz each) and a Higley Heavy Hub (2.5 oz.). That means this LT needed 11.9 oz of weight. This is with a totally naked firewall / engine combo.

Everyone says "add useful weight" rather than lead. Em, how big an engine is still "useful"?

Now to see how it flies.

wcmorrison

My Feedback: (2)

Make sure you reinforce the firewall.  The power stroke of a Saito 91 is considerable and it can cause the glue to fail with time.

Chip

soarrich

My Feedback: (98)

The good thing about lead is it can be removed. I flew my LT-40 with the CG way back from where it was in the book, the plane gets much nicer to acro with with the Cg back. This plane does super slow Cuban 8s which was my favorite maneuver. I had huge throws on mine.