Engine basics > Engine set up tips
List "YOUR" set up for the OS .46LA
Bill Little:
Run Style: (4-2-4, wet 2, solid 4)
Venturi:
NVA:
Prop
Make:
Diameter and Pitch:
Fuel
Brand:
Nitro%:
Oil% and "Blend":
Quantity used:
Frank Imbriaco:
Bill,
Hope you get good feedback here. I've got an OS .46 LA that I just completed a light break in( 20 ounces of 5% Nitro, 20% castor ). I got rid of the remote NVA , plastic backplate and stock venturi. Using the NVA and venturi from the OS 25LA with an additional headshim.
I did the break-in using an 11-4 Zinger and plan to start with an 11-5 XOAR in the air. After a half dozen or so flights, I'll be going to 10% nitro and a 20% synthetic/ castor blend. Using a tongue muffler.
The aircraft is a Nobler and it will possibly be over-powered, so I'll likely run it 4-2 if it'll cooperate.
Just waiting for the weather and field ground conditions to improve.
Steve Helmick:
Bill...I'd suggest adding "muffler type & brand" to the questionaire. It can make a lot of difference on the rest of the setup, and 'specially on fuel mileage. Might ask about muffler pressure or not, also.
I used my .46LA (Tower .40 backplate, .285" venturi, .156" spraybar, 10-22 Powermaster and 11.5 x 4 APC) on a Humongus, and it worked well for that plane with a MACS Muffler, launching at 10.2k or so. Slightly wet 2 stroke. Great fuel economy, easy to setup, start, and fly.
I eventually tried a Big Art tube muffler with a 12-5 APC, everything else the same except launch rpm. Liked the run a lot, but it wasn't fast enough for the Humongus, and the fuel economy was not nearly as good. Sounded like a 4-2-4, but maybe just bogged down. I still think it would have worked nicely on a Profile Cardinal or a classic.
I put that engine into Don McClave's old white Skylark with a Randy CNC Tube muffler on muffler pressure. It worked ok with the 11.5 x 4 APC, but I had to reduce the venturi to .272" to work with the existing fuel tank, and the Bolly CF LG was marginal with the 11.5" prop. The model still exists, but it never had much line tension up high. I do have some ideas to make it work better. I tried a 10.5 x 4.5 "Magic" prop with poor results, and some Bolly 12 x 4.25 3-bladers clipped to 11", with nothing good happening. I'd like to try the 12.25 x 3.75, 12-4, and 12-5 APCs, or at least a 12-4 Xoar. The LE of the fin is kinda blunt, and I'm thinking that maybe it's a problem. I'll re-shape the fin LE sometime soon. H^^ Steve
Joe Messinger:
I have three Brodak Cardinal profiles that are powered by OS LA .46 engines. The set up that seems to work best for me is:
*APC 12-4 prop.
*Mac's muffler.
*Muffler pressure.
*.285 venturi.
*Randy Smith NVA.
*Aluminum back plate.
*Brodak 10%-11-11 fuel.
*5 oz. Sullivan clunk tank.
I have not been able to get a true 2-4 engine break with these motors. Perhaps another combination of the above would allow this but I'm quite happy with the wet 2 stroke run that it produces. I might add that I am not an expert flyer. Mostly week end sport flying so that might be taken into consideration. I have tried a good number of combinations with this engine/plane and as I mentioned, so far, this particular set up works best- for me.
Joe
Brett Buck:
--- Quote from: Joe Messinger on April 04, 2011, 04:52:09 AM ---
I have not been able to get a true 2-4 engine break with these motors.
--- End quote ---
It can be done (seen several that way), but there's no reason to, it provides much better performance when run the way it is intended.
Brett
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