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Brian
The problem with your statement is I can build a real 327 with around 500 h/p for $4000 lol. But did you see the beautiful Charger and GTX they are building and selling??? They look sweet
 
It says glow wiring in the description. Cobra rocker covers with small block Chevy manifolds?
 
Actually if they have the glow plug wiring running through the distributor, and it looks like they do, that would help in a couple of ways. You could hit the glow plugs with a higher voltage for just a short time and not burn out the plugs, maybe even all 12 volts depending on the distributor dwell. A lot of the white strobes on radio/TV towers are actually 120V bulbs running on 240V. Because they are only turned on for such a short time the filament does not melt and it has a chance to cool between flashes.

The same would be true for the plug in an 8 cylinder engine. Another plus would be that you'd get a hotter plug just when you needed it. This also would mean that you're only running 1 plug at a time, so the current draw would be MUCH lower than trying to light up all 8 at once. You wouldn't need points either, you could just use the distributor rotor as your switch.

Don
 
Hi Don. Have you ever seen a distributed glow system like what you are describing? I don't quite follow what pulsing the plug at elevated voltage accomplish? If the element manages to glow at a typical (call it low or normal) voltage & that temperature manages to auto-ignite the fuel mixture as designed, then why would a hotter/shorter duration be better? I would think once the flame is propagating (however it became ignited) its pretty much on its own path & speed. Its not really like a timed spark ignition where ignition is triggered by an arc over a gap at a prescribed timing point. In glow, ignition happens when it happens & driven by a whole bunch of factors like fuel, compression, breathing... but those are by & large fixed (while running).

Model glow is more like a semi-dieseling ignition. The wire temp goes from 'hot glow' near ignition to 'low glow' during induction. But never goes to 'no glow' or it wouldn't sustain running. Unless of course it has a background voltage perpetually hooked up. But probably 99% of RC engines require no external battery one running unless for idle/insurance or other factors. Usually its because the rpm is low or too much cooling time between cycles, the element has dimmed to a point it wont reliably auto-ignite. So with a full time battery on (or triggered on at low throttle) it maintains minimum temp to self ignite. The non-ignition glow period is just waste heat energy that doesn't get in the way of the normal cycle.

Also just because you boot the voltage up so the wire element ramps to elevated temperature or quicker, there is no back side control as to how fast the element cools on its own unless the element was specifically designed for this (custom glow plugs). I would think 'de-glowing' is largely dictated by the element diameter, composition, engine breathing etc.

I don't have any design experience but I have run a lot of plugs and all it takes is a little bit of a lean run which to raise head temperature & the plug element is baked & frazzled. I think if there was a longer lasting alloy that could sustain elevated & cyclical heat. we probably would have seen it by now. Even so, good high performance glow plugs are getting spendy.

My understanding is a lot of modern glow plug drivers are basically on/off pulsing regulated voltage just like you say (as opposed to a fixed voltage from a cell battery). And many even have a heat control knob. But there isn't much latitude on the high side, you can burn the element if set on high if left too long before starting.
 
Badhippie said:
Brian
The problem with your statement is I can build a real 327 with around 500 h/p for $4000 lol. But did you see the beautiful Charger and GTX they are building and selling??? They look sweet
Click to expand...
I'll bet you could do that except - - - - can you put that full size 327 on your desk and impress your buddies/customers with something none of them has likely ever seen before?
Thought not - - - these are toys for those that want something that very few have - - - and for the even fewer that can afford them (or the tons of time making them).
(Post Scriptum - - - If I want a full size I'd prefer either the Scania 673 or the Cummins KTA 1150 - - - grin - - - - might be able to come up with some others if I'm spending other people's money - - - grin!)
 
I spent a lifetime building and drag-racing hotrods. Everything from 265, 283, 327,and 350 General Motors engines up to Ford 390 engines. Yes, you could buy a fully assembled long block for less than one of these micro-engines cost. Heck, you could generally buy a used car for less than that. If the guy is using cnc machining to produce these engine parts, he will still have a ton of time in painting, anodizing, assembling and trouble-shooting before he has a finished, saleable engine. If I was to make one of these engines, finished to the state these engines are, on my manual machines, I would want at least $10,000 for one. So---It doesn't look like a bad deal to me.
 
Brian
You are correct and if I recall Conley was selling his engines for around $7,000 US dollars. I to have spent almost 40 yrs building and machining engines from 5 h/p Briggs to 2500 h/p hemi’s to 1800 h/p 6cyl Cummins to 5600h/p locomotive engines both EMD and GE this is all I know and have been doing since I was 13 yrs old. I have devoted my entire life to engines and machining I have went from full time engine builder to full time machinist now. Working for one of the largest corn milling plants in the world. As well as Citric Acid and other food products. I like to call this my retirement job.
 
Petertha:

Never seen any distributed glows system like that, just brain-storming. Like I said, something similar is/was used for the white strobe light on a lot of North American transmission towers. I was told that the bulbs used were not some fancy strobe light, just a standard 120V incandescent bulb that was pulsed with 240V. This short higher voltage pulse heats the filament to a much higher level, the whiter the light - the hotter the filament. The reason the filament doesn't melt is that the duration of the high voltage pulse is very short.

A glow plug has a filament similar to a light bulb so I was just thinking out loud, wondering if you could do the same with a glow plug. You definitely wouldn't want this system to run 100% of the time, that's why I was thinking you could use the distributor rotor to switch the plug on and off. But even that would probably be too long, and you just burn out the plug. Also if the engine just happened to stop in just the right position, or just the wrong position - depending on how you look at it, the plug would be lit and you'd burn out the plug.

It might work, it feels like it could work, but it would probably take several iterations before you actually had a reliable working system.

Don
 
I have one of these engines and there is a voltage regulator for each glow plug that drops 12 volts DC down to the 1 1/2 volts needed for each glow plug to glow. That distributor is nothing more than a hollow plastic piece that the glow plug wires run through to make it look real.
bruski
 
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