SPA Engine (2 stroke .61 side exhaust)
 

What would you put in a Dirty Birdy or a Mach 1? New or vintage, doesn't matter just trying to get some ideas. - something that's relatively easy to obtain.
I've been mulling over the K&B Twister 6050, HP Gold Cup, SuperTigre S61 (already own), or even a Fox Eagle (I aint skeerd), Rossi ect, you know, something with charactor. I also want it to pull the plane around like a rag doll. : )

RE: SPA Engine (2 stroke .61 side exhaust)
 

Keep the DB light. Around the 7 lb arena. Mine weighed in at 7#-4oz, put a ST S61 with tune pipe (it was a quiet pipe so called),l 11x7 3/4 prop plane equipped with retracts.
Today I would do the same, only use APC 11x8.
Main thing is keep the plane light and don't worry about the wind. It'll dom just fine.

I have a new all wood DB in the box to be built, and have a ST S61 wating for it with Robart mechanical retract (two wheel) same as old.

Crashlander

RE: SPA Engine (2 stroke .61 side exhaust)
 

i've got a just barely broken in hirtenburger .61 w/ muffler that has outstanding pull. i would sell it cheap. it's not a gold cup though.

david

RE: SPA Engine (2 stroke .61 side exhaust)
 

I flew my Dirty Birdi's with a Webra Speed .61, flow thru muffler (no tuned pipe), Southern retracts. Perfect combo. I used a Kraft .61 (now RJL) on my Mach 1. Not as strong as the Webra. I have a new Webra Speed .61 for my "on the board" Tiporare.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

Allthegoodnamesaretaken,

I have a Dirty Birdy 60 kit from Bluejay. I plan on putting Rhom-Air retracts and a pumped K&B61 in it without a pipe. I plan on keeping the model as light as possible. I just hope the old K&B will be enough..:eek:

RE: SPA Engine (2 stroke .61 side exhaust)
 

A light Dirty Birdy will do very well with an OS 55AX. A friend has one and he's got plenty of power.

RE: SPA Engine (2 stroke .61 side exhaust)
 

I also have an OS .55AX, and it is a great engine for overpowering .40 size airplanes, I've also had two Dirty Birdi's, but I don't think you can build a Dirty Birdi light enough to have it perform as it would with an average .60/.61 size engine much less with a high performance .61.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

Depends on how you want to use the DB. If you want to compete, I recommend a high performance .61, such as Webra Speed, HP Gold Cup, Rossi, Jett. If you're just going to sport fly, your ST should be fine.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

Get one of these, or an OS 61 SF, or OS 61 FSR. Lot of good powerplants out there. Also, if you don't mind rear mounted NVA go fo an OS 61FX or the 75 in the 61 case.

Crank

RE: SPA Engine (2 stroke .61 side exhaust)
 

I agree... there quite a few really good engines out there.... including the OS .75AX. I have one of these as well. Need to be careful though, if you expect to compete, the .75 will be illegal in all the "old time" pattern events.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

It's legal for BPA.....yahoo.

Crashlander

RE: SPA Engine (2 stroke .61 side exhaust)
 

I downloaded BPA "rules" a few days ago, and I'm pretty sure the .61 limit for two-strokes is in effect.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

What about the "Fly Anything", in SPA Novice ? A guy shows up with a 50cc powered Extra ?

Crank

RE: SPA Engine (2 stroke .61 side exhaust)
 

You're right... I concede.

By the way, what a beautiful job you're doing with your Phoenix finishing thread. I applaud you.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

Thanks Chief. That Phoenix 6 has traveled around with me for about 30 years. Finally getting back to it. I have more Phoenix' here, and may get another 6 together after this one. There is two Vertigo's here also, so lot of stuff to do.

I have more projects to do here around the house, and I work part time, so the building has gotten a little slow right now. Should try to get the fuselage painted next week if it drys out here. Lot of storms in the last 10 days, and now another down by Cuba, looks like it will miss us. I have been thru hurricanes, five in Wilmington, NC and three here. House is 155 knots proof, metal roof and all the good stuff. I am attaching the control surface's soon on the P-6, run nylon tubing where needed, get some JR DS821's.

Thanks for the nice comments, stay tuned.

Crank

RE: SPA Engine (2 stroke .61 side exhaust)
 

I decided to use the NovaRossi C60F side exhaust with a tuned pipe. Now should I build the Dirty Birdy or Mach 1?

RE: SPA Engine (2 stroke .61 side exhaust)
 

is that the 8 port novarossi?

david

RE: SPA Engine (2 stroke .61 side exhaust)
 

The Mach 1. I will look in the box, not familiar with Rossi. If this works, then I will get another one or two. More engine stuff coming, OS 61 SF, dunno much about them, I just want to get away from the rear NVA on the OS61FX.
Crank

RE: SPA Engine (2 stroke .61 side exhaust)
 

I've had both the DB and the Mach 1. They're both great planes, but I think my DB's flew better than my Mach 1. I see Crank is recommending the other way. You'll have to make up your own mind.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

I too prefer the DB over the Mach 1, in flight performance. The DB is more symmetrically designed. The Mach 1, while beautiful, is a very assymetrically designed model. Give me symmetry and a long fuselage any day.


Ed Cregger

RE: SPA Engine (2 stroke .61 side exhaust)
 

Yep. Only $200! With the tuned pipe and header.

RE: SPA Engine (2 stroke .61 side exhaust)
 

Yes the Mach 1 is sexy. That's why I want to build one. I hear nothing but good things about the flight performance of the Dirty Birdy and it has some very classy lines as well.

Well, as soon as the brown truck gets here I'll get started. Maybe a build thread is in order? Haven't seen one yet on the DB.

I'd like to do retracts too. But I'd like to make it a tail dragger to save weight. I'm sure that's been done before.

Thanks for the input guys. : )

RE: SPA Engine (2 stroke .61 side exhaust)
 

You're going to use a NovaRossi with a tuned pipe and then leave the wheels hanging in the wind?????? Say it isn't so.

ChiefK

RE: SPA Engine (2 stroke .61 side exhaust)
 

good point! why?

david

RE: SPA Engine (2 stroke .61 side exhaust)
 

What I meant was I want retracts. - yes. I also want to make it a tail dragger not use tri-gear. Anyone built a DB as a tail dragger WITH retracts? I imagine its just a matter of moving the main gear forward?