LA 40 on a pipe

Wondering has anyone put a LA .40 on a pipe and if so how did you set it up.
I have a LA .40 I'm running it on a plane I built myself I baught a set of Oriental wing ribs from Brodak I built the wing to 53" with a nose of 8 3/4 and a tail of 14 3/4 it just turned out that way she flies great. I originaly put a OS 32 f with a Randy Smith pipe on her and toyed around and got her working good but now I have a LA .40 and was wondering can I pipe a LA .40 and if so how do I do it.
Thanks
Dwayne

>Wondering has anyone put a LA .40 on a pipe and if so how
>did you set it up. (snip)
>Dwayne

I am sure a number of people have done this. I know Igor was running an LA 46 on his for a while. You might check with him.

Basically you need a side to rear header, a 40 size or larger pipe, and then find the right combination of pipe length, prop diameter and pitch, along with rpm, venturi size, head shims, and fuel. It is this latter "combination" stuff that might drive you bonkers for a while. There is no such thing as "this is the right set-up". You can find certain starting points that might get you into someone else's ball park, but a lot of set-ups re merely personal preferences or someone not having tried something else.

If you are still venturesome, let us know how you fare.

Johnny Duncan has one in his Vegas. I flew it and it was excellent. I worked with a piped LA46, struggling for six weeks with it before abandoning it and dropping in a PA 40-UL.

No doubt it can work, but I ran ran outta patience.

RC

A few years ago, Curtis Comer was using a 40LA on a profile to work out the set up for pipe length, etc., and had it running great. He was planning on using it in a built up plane, but went "larger", in other words, bigger plane and a regular "pipe" motor. But the set up worked real nice or him.
Bill <><

I would try your set up off the 32F as I beleive it should all bolt right up to the LA 40.They have the same bolt spacing on the exhaust port.I am no expert but I would give it a try.

Our friend Gerald Phelps of Patriot fame flew a Patriot look alike at the Lubbock Nats and perhaps the following Pasco Nats.

LAST EDITED ON Oct-09-04 AT 07:49 PM (CDT)
 
I put a tuned pipe on an OS 40 LA last summer. The RPM's increased and we times the airplane at 10 mph faster. I made my own tubed pipe form brass hobby tubing. I used a large diameter tubing I beleive it was 5/8" and 9/16". The 9/16 will slide inside the 5/8 tubing perfect fit. I used a copper plumbing reducer to reduce each tube down. I attached the 5/8" tube to an elbow to the engine. I reduced the 9/16 down to 3/8". I started the engine without the 9/16 tubine attached. The needle was a little rich. With the engine running I slide the 9/16 tubing inside the 5/8 tubing and slide it back and forth like a slide trombone. As I slide the tubes together very slow I came to a spot where the engine RPM's came up very high and the engine leaned out and died. I screwed the needle out 1/2 turn and restarted the engine. I moved the tube in and out about 1/4" to fine the correct spot and attached it permently. The airplane went a lot faster than before and burned more fuel. I changed the prop up 1" on diameter and down 1 on pitch, readjusted the tuned pipe and did another test flight. It seems to me if you want more power out of an OS 40 LA then use an OS 46 LA and forget the tuned pipe its a lot less trouble. If your like me and love to tinker with stuff then give it a shot.

>I put a tuned pipe on an OS 40 LA last summer. The RPM's
>increased and we times the airplane at 10 mph faster. I
>made my own tubed pipe form brass hobby tubing. I used a
>large diameter tubing I beleive it was 5/8" and 9/16". The
>9/16 will slide inside the 5/8 tubing perfect fit. I used a
>copper plumbing reducer to reduce each tube down. I
>attached the 5/8" tube to an elbow to the engine. I reduced
>the 9/16 down to 3/8". I started the engine without the
>9/16 tubine attached. The needle was a little rich. With
>the engine running I slide the 9/16 tubing inside the 5/8
>tubing and slide it back and forth like a slide trombone.
>As I slide the tubes together very slow I came to a spot
>where the engine RPM's came up very high and the engine
>leaned out and died. I screwed the needle out 1/2 turn and
>restarted the engine. I moved the tube in and out about
>1/4" to fine the correct spot and attached it permently.
>The airplane went a lot faster than before and burned more
>fuel. I changed the prop up 1" on diameter and down 1 on
>pitch, readjusted the tuned pipe and did another test
>flight. It seems to me if you want more power out of an OS
>40 LA then use an OS 46 LA and forget the tuned pipe its a
>lot less trouble. If your like me and love to tinker with
>stuff then give it a shot.
>
>Gary Weaver

Ron B.
F4Fguy

Gary: You're kidding ,right?????

LAST EDITED ON Oct-10-04 AT 09:46 AM (CDT)
 
>
>Gary: You're kidding ,right?????
>
>Ron B.

Nope not kidding. I don't have the pipe for the OS 40 any more, I don't have the airplane either so I can show you that one.

Here is the same type of tuned pipe on my OS Max 25 LA. It weighs less than half the weight of a stock muffler and gives the engine probably 20% more power. I put a very large fuel tank on this airplane it will fly for 15 minutes with a full tank of fuel and the stock muffler. It will fly for 12 minutes with a full tank of fuel and the tuned pipe.

I learned this slide tube method of making tuned pipes when I was racing go carts. When your on the race track you need all the power you can get coming out of the curve. The engine speed is a little slower coming out of the curve probabay about 5000 RPM compaired to 7200 RPM at the end of the straight away.

I tried the slide tube method on my OS engines and it works fine. Once you find the correct length it works only for the setup you have. If you change anything like the fuel, prop, venturi size it goofs things up and you have to slide the pipe in or out to find the correct tuned spot again. I soldered this pipe in place so I have to remember to use the correct fuel and prop with this pipe.

I'll be darned, Ron the guy wasn't kiddin!!!!!!

Ron B.
F4Fguy

Gary: You're kidding ,right?????

Ron B.

Yes, Len is right. I have no experience with .40, but I used LA .46 in two models - one of them was on WC 2002 in Sebnitz and finished on 10th place. That combo works very well, I never even dismounted the engine from the model or shimmed the tank - all works for first try. The only problem is side exhaust, but original OS manifold and engine position at 45 deg solves it safely, pipe comes exactly to center of fuselage.

More you can find on:
http://www.netax.sk/hexoft/stunt/the_max.htm
http://www.netax.sk/hexoft/stunt/the_max_ii.htm

Thaks guys!
Dwayne

>Thaks guys!
>Dwayne

Dwayne,

I think you need to be more specific here. 'Cos if you're thanking Gary Weaver, you just took a huge head fake...

Incidentally, "trombone" pipes from the world of karting are hardly an unknown to many of us. But even these specialized pipes look a lot like a normal setup, whether collapsed or fully extended. In any case, they look nothing like what Gary has tossed together.