"vondon302" (vondon302)
04/18/2019 at 08:27 • Filed to: antonov
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"vondon302" (vondon302)
04/18/2019 at 08:27 • Filed to: antonov | 0
| 10 |
L ets get fired up today!
Ssomeone want to tell me why the exhaust gets red hot so quick. Is he running super rich or is it just because radials don’t usually have exhaust pipes?
Nibby
> vondon302
04/18/2019 at 08:35 |
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idk about his exhaust but he should use one of these at home
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vondon302
> Nibby
04/18/2019 at 08:36 |
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Clicky clackty is the best.
OPPOsaurus WRX
> vondon302
04/18/2019 at 08:47 |
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Im guessin g it has something to do with all the fire shooting out
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vondon302
> OPPOsaurus WRX
04/18/2019 at 08:54 |
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Ya think?
Snuze: Needs another Swede
> vondon302
04/18/2019 at 09:01 |
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There are a few factors. First, they look to be relatively thin walled steel tube headers. If youve ever noticed in dyno videos, most production cars have cast iron manifolds which have a lot of heat capacity, so they either don’t glow or they glow dimmly and take a while to get to that point. Headers are thinner, with less mass, and will reach that glowing point faster, and glow brighter.
Another thing is that the engine could be in a, for lack of a better term, different state of tune. Aircraft engines are meant to operate at high altitudes in air that is much colder but also less dense than what we’re used to experiencing. Aircraft engines also typically run at relatively constant load/RPM. I don’t know much about Antonov engines but most aircraft engines like that were supercharged, multi-speed supercharged, turbocharged, or compound charged (turbo and super). So a tune that works best at the altitude/speed/load the plane normally runs at is probably not ideal at sea level. Remember too that it’s probably carbureted or has a rudimentary mechanical injection system which is going to have much less tuning capability than a modern EFI system.
That said, the heat and fire coming out of the pipes could be a result of a rich mixture. Rich mixtures tend to run cooler than ideal, but it would explain the fire coming out of the ends of the pipes -superheated fuel entrained in the exhaust gasses self combusting when they mix with oxygen in the atmosphere. Also early exhaust valve opening or late ignition timing means the air/fuel mixture could still be burning as it leaves the combustion chamber which would also explain the heat and fire.
Jetstreamer
> vondon302
04/18/2019 at 09:03 |
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Probably running rich for the show. Plus maybe higher than regular RPM (they were made with a ‘redline’ of 2100RPM for maximum continuous power in the planes they were mounted in, and would normally be run between 1700-2000RPM. And I’m pretty sure that tiny fan upfront does not equal a nice 60-200km/h airflow keeping things cool.
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OPPOsaurus WRX
> vondon302
04/18/2019 at 09:03 |
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SSomeyimes
It's not consistent tho
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vondon302
> Snuze: Needs another Swede
04/18/2019 at 09:19 |
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Good point on the thin wall tubing.
I love it when a response is better written and more thought out than the original post.
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Snuze: Needs another Swede
> vondon302
04/18/2019 at 09:28 |
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Well, you asked the question, so I wanted to give it a proper reply. And it’s good to flex the brain muscle on this kind of stuff, caused me to look at a few articles real quick to make sure I remembered everything correctly.
I’ve also been looking at that kind of stuff lately because I’m getting ready to redo my old Honda Nighthawk 250 engine. The bike frame and some ancilaries (like the mufflers) are trash, I’m thinking about sticking the engine on a gokart or buggy, so I’m gonna run it open heade, but that means more flow and thus I’m gonna need more fuel. Those engines run lean even in stock trim so I want to make sure I don’t burn it up.
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vondon302
> Snuze: Needs another Swede
04/18/2019 at 09:33 |
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Sounds cool.
Thx and well done.