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.049 medalion ?

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.049 medalion ?

Post  oldguy on Sat May 26, 2018 1:48 pm

What would be the single most thing to do to the medallion to increase performance? High comp head, change venture out to the TD style., piston&cylinder.
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Re: .049 medalion ?

Post  Ken Cook on Sat May 26, 2018 2:16 pm

If your going for more rpm's, the high comp head will offer a few hundred more rpm's. It's only a single bypass cylinder. Changing to a dual bypass cylinder will ultimately offer the most rpm's but the fuel economy is going to diminish.
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Re: .049 medalion ?

Post  Cribbs74 on Sat May 26, 2018 3:52 pm

What are your plans for it? A lot depends on the intended use. For Control Line, what Ken says is the best bang for the buck. The Medallion venturi is also best for Contol Line.

Ron
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Re: .049 medalion ?

Post  oldguy on Sat May 26, 2018 6:57 pm

Ken Cook wrote:           If your going for more rpm's, the high comp head will offer a few hundred more rpm's. It's only a single bypass cylinder. Changing to a dual bypass cylinder  will ultimately offer the most  rpm's but the fuel economy is going to diminish.


Ken yes a little more R's. Let me say I already installed a #1 piston cylinder set on it. I believe the #1 is from the black widow. Is that correct? I know the high compression head is the way to go, but I have several of the stock heads. Question can you take a stock head and shave off some of the head to create more compression or is there more to the high compression head than a smaller chamber?
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Re: .049 medalion ?

Post  oldguy on Sat May 26, 2018 6:58 pm

Cribbs74 wrote:What are your plans for it? A lot depends on the intended use. For Control Line, what Ken says is the best bang for the buck. The Medallion venturi is also best for Contol Line.

Ron

Ron it's just for control line fun sport flyin.
Thanks
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Re: .049 medalion ?

Post  Ken Cook on Sat May 26, 2018 7:05 pm

One thing to understand here is that more nitro would offer more power. Reducing your compression and raising your nitro would be in order. The problem is that you need to discover the sweet spot of head shims required . Using high nitro without proper head clearance can be pretty rough on a $10 plug essentially eliminating it in one run. Running high nitro isn't going to harm the engine as many claim. Unfortunately, it's expensive. 45% nitro is my standard 1/2A fuel. Your only going to get so much out of the Medallion, if your in search of more switch to a TD. The crankshaft timing is the limiting factor here.
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Re: .049 medalion ?

Post  Cribbs74 on Sat May 26, 2018 7:10 pm

oldguy wrote:
Cribbs74 wrote:What are your plans for it? A lot depends on the intended use. For Control Line, what Ken says is the best bang for the buck. The Medallion venturi is also best for Contol Line.

Ron

Ron it's just for control line fun sport flyin.
Thanks

Well, then what’s it on? I ask because it’s usually stout enough for sport flying, and especially with a #1 cylinder on it.

The difference in heads is the combustion chamber size and shape one is hemi and the high comp is trumpet shaped. you can shave a little off of a stock head, but it still won’t equal the performance of a TD head. We are only talking a couple hundred RPM here so gains are minimal.

How heavy is the model?

Ron
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Re: .049 medalion ?

Post  oldguy on Sat May 26, 2018 7:36 pm

Cribbs74 wrote:
oldguy wrote:
Cribbs74 wrote:What are your plans for it? A lot depends on the intended use. For Control Line, what Ken says is the best bang for the buck. The Medallion venturi is also best for Contol Line.

Ron

Ron it's just for control line fun sport flyin.
Thanks

Well, then what’s it on? I ask because it’s usually stout enough for sport flying, and especially with a #1 cylinder on it.

The difference in heads is the combustion chamber size and shape one is hemi and the high comp is trumpet shaped. you can shave a little off of a stock head, but it still won’t equal the performance of a TD head. We are only talking a couple hundred RPM here so gains are minimal.

How heavy is the model?

Ron

Well I will run it as is then. It's like a 1/2A VooDoo, plane with tank and engine weighs 5.4 oz.

thanks again guy's.
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