Stalker .66 vs Discovery Retro .61LS

[Randy Powell]

Any thoughts? I'm considering one or the other for a project I'm working on.

I'd appreciate input.

[Bill Little]

Any thoughts? I'm considering one or the other for a project I'm working on.

I'd appreciate input.

My input?? I would *probably consider* a PA since they are made in the US and help is very easy to find......... plus they are fantastic runners!

[Will Hinton]

What Bill said, and if you're not a fan of the pipe remember that Randy has them in whatever mode ya likes.  You simply set the needle in June and forget it 'til cool weather hits hard!  Flip n fly is the result of using PA's.
Blessings with the new project.
Will

[Randy Powell]

No knock on Randy or Richard. I have engines by both and like them a lot. But I wanted to try something in a project I have in mind that is the low rpm, higher pitch setup. The Discovery Retro seems a good candidate as does the Stalker.

[Kim Doherty]

Randy,

I do not think it is much of a contest. The Retro .61 is (IMHO) simply the best non-piped conventional LS motor available. More grunt than you will ever need. (assuming 60 - 62 ounce auw) Use the right props and the right fuel and you will be very, very satisfied. I've lost to lots of them.


Kim.

[John Miller]

Hey Randy,

You know I'm a fan of Stalkers, but so far the only .66 I've heard of that's running real good is our friend Ressinger's, up in CANADA.

You didn't say whether you already have the engines, our are planning on buying one, so I'll go on the presumption that you're going to buy a new engine.

I like the way Jimmy Rhoade's Discovery runs. Like the Stalkers, they are very consistent, but, I've been told that the Discovery runs best side mounted. Does that make a difference to you?

Until I'm sure that the ST .66's are all running like Alan's, I would stick with the Stalker .61's. There are several available. One that is most like what you are looking for might be the .61LT. It has a longer stroke than the one in my Legacy, which is the 4-2-4 version.

If you want the bigger bore, You could consider the ST .76, which I understand, is finally available. Kaz has been using one, and reports being quite happy with it. If you want to go with maximum grunt, and .21 lines, go with the .81.

Best wishes for the holidays,

[Wynn Robins]

Randy

Go with the Stalker - most of the guys here in NZ and Australia have ditched the Retros in favour of the Stalker - I have one now ready for a Dreadnought that I have nearly finished - they are a fantastic engine.

Brian Eather (in Aus) commented that the Stalker 66RE is the best stunt engine he has ever used....those are pretty big words coming from him!!!

get one. try it, if you change your mind - i'll buy it off you.

[Walter Hicks]

Hi Randy,

    I love my Stalker .66, runs like a charm. I have not finished my KA -10 yet so I have no experience with the

Discovery Retro. I believe Kaz Minato likes the Stalker  somewhat better as he says it is user friendly.


The Stalker .66 is an excellent motor, starts one flip every time, holds its setting and has a beautiful mellow

stunt run. I use 10/18 Powermaster fuel nothing added. I believe I have two head gaskets added.

Also the Stalker Muffler is much easier to deal with than the Retro. The .66 Re muffler bolts on to the case.

     I also have the Stalker .81 , however it is a low RPM engine 7000 or less!!!  I needed a 13x8 prop to get what I wanted. 

[Walter Hicks]

Retro:

[Walter Hicks]

Stalker .81:

[John Miller]

Ya almost got me mixed up with those two pictures. When I first looked at them, it was rather a fast glance. Thought at first it was two different views of the same engine, then I looked closer, and noticed the differences. I realized that the top pic was of the Discovery, while the bottom pic is of the Stalker .81.

My .81 won't rev past about 7800 rpm. Like you, I'm convinced that it'll be pullin' all I want at about 65-6900 with a 7 or better prop. Sort of like a four stroke set up.

[Will Hinton]

Those are both sharp looking engines - I really have to fight the urge to buy many different engines just to have them on the wall to look at!  There are times I hate to run one because I know it's gonna get brown sooner or later.  It's not the cleaning I dread, it's just the covering up that beautiful bright look!  (Then spring comes and I need the smell of burnt castor in the morning!)
Blessings,
Will

[Bradley Walker]

Brian Eather (in Aus) commented that the Stalker 66RE is the best stunt engine he has ever used....those are pretty big words coming from him!!!

Brian still says the 61 is better in the wind.

I want one...

Although, like Bill Says I am getting stellar low RPM, high pitch runs out of my PA 65.  I am running at 7800 RPM on a TF 13-6 and many local fliers are very impressed with my setup.  I have the break switching as good as I have ever heard, including all the baffle engines I have worked with, and the setup is very good in the wind.  I am burning 4.25 oz of fuel.  I supposed my run is similar to a Stalker/Retro.  All I know is a hand start and fly.

So, the PA 65 is a real good engine too.

[RandySmith]

No knock on Randy or Richard. I have engines by both and like them a lot. But I wanted to try something in a project I have in mind that is the low rpm, higher pitch setup. The Discovery Retro seems a good candidate as does the Stalker.

Hi Randy

As always you should Buy whatever engine you feel will suit your purposes, however just so wrong info does not get out there, and this is the only reason for my post here:
 The PA line of engines run extremly well on higher pitch lower RPM setups, and if fact won the US NATs with just such a setup. You just have to set them up for this as you do *any* engine. You will not find an engine as versatile as the PA line. I have ran a 61 in my INTREPID with a 3.6 , 3.8, 4.25, 4.75, 5, 5.5, and 6 pitch props, all with the exact same engine.
They have been running in many planes all overe the globe with high pitch lower RPM and mufflers, either rear or side.
I have heard this many times from many people about PA engines are hi RPM motors  only. It simply is not the case, by the way KAZ is running a PA 75 in his ship.  Many Yatsenko airplanes have PA with higher pitch lower RPM runs  also, I have personall flown many of them.

Have fun

Regards
Randy

[Randy Powell]

Randy,

That's the way I run the .40 Merlin I have. RPM is about 8800 with a 5 pitch. I've tried it at about 7800 with a 7 pitch, but it wasn't very happy there. Much better run with the 5 pitch at 8800 or so. Very strong engine (and going back in the Cobra as soon as I complete the re-finish).

I may consider a PA 75. I'm considering building a new elliptical design with a molded fuselage and modified radial cowl. It's based (loosely) on a 30s air racer. Thought it would be a good candidate for a low rpm, higher pitched prop setup. I watched Alan Resinger fly his Firecracker with a Stalker .66 and was pretty impressed with the run. Sort of an ST 60 on steroids. It may be that the PA 75 would be a good choice for the same sort of 4-4-4 run Alan was using.

[John Miller]

Something like this Randy?  I think the PA set up for low spped higher pitch will work fine.

[Gordon Tarbell]

That looks kinda like the JB special that I have been waiting for .

[Randy Powell]

John,

Not even close. Mine is, ah, hard to describe. It's about 8 inches through the fuse at the high point of the wing. It is a FAT BOY!