How many plugs would a combustion chamber plug if...
- Ron LaDow
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How many plugs would a combustion chamber plug if...
Seriously, looks like the F1 guys have developed a way to start the ignition in several (many?) places from one plug:
https://www.youtube.com/watch?v=wzj_NDmOzO0
https://www.youtube.com/watch?v=wzj_NDmOzO0
Ron LaDow
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Re: How many plugs would a combustion chamber plug if...
Thank you Ron, a really great post. And how simple it all is. One of those ideas that just looks so logical, so obvious, you wonder why it took so long. What if it could be adapted to a 356 engine. Count me in. Thanks again, jim
- Ron LaDow
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Re: How many plugs would a combustion chamber plug if...
Jim, that'll be offered for 616 engines about the time 4-valve heads are. There is no way the tech required would work with even 12V, carburetted, air cooled engines.
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Re: How many plugs would a combustion chamber plug if...
Invented by Honda around 1970...CVCC. Improved by electronics and the addition of more flame ports. Those damn Germans are always stealing ideas from the Japanese.
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Re: How many plugs would a combustion chamber plug if...
So hypothetically you'd need to redesign a head with the pocket chamber and, the engine would have to be fuel injected? The closest in concept we have now is the twin-plug engine, right?
Mike Wilson
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- Ron LaDow
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Re: How many plugs would a combustion chamber plug if...
Mike,
"So hypothetically you'd need to redesign a head with the pocket chamber and, the engine would have to be fuel injected?"
I think so, and it would probably need to be CPU-controlled.
If you examine a chamber in 2D (which has done fine for predicting the lead for the twin-plug), you can see that the best is a single plug, dead center.
Cliff says 2-plugs are a band-aid and I agree; if I could change the 616 chamber geometry and get one in the middle, that would be better. Any additional quench area you can find is gonna benefit a twin plug at least as much as a single, so that isn't anything like a substitute for the second plug.
Added by edit:
X in all cases = minimum flame travel required to burn the entire chamber
"So hypothetically you'd need to redesign a head with the pocket chamber and, the engine would have to be fuel injected?"
I think so, and it would probably need to be CPU-controlled.
If you examine a chamber in 2D (which has done fine for predicting the lead for the twin-plug), you can see that the best is a single plug, dead center.
Cliff says 2-plugs are a band-aid and I agree; if I could change the 616 chamber geometry and get one in the middle, that would be better. Any additional quench area you can find is gonna benefit a twin plug at least as much as a single, so that isn't anything like a substitute for the second plug.
Added by edit:
X in all cases = minimum flame travel required to burn the entire chamber
Ron LaDow
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Re: How many plugs would a combustion chamber plug if...
That makes sense to me, Ron. Looking at a head, I don't see how you could position a spark plug in the center due to lack of room between the valves. I can see why the twin-plug was developed. Maybe a different chamber configuration like John Willhoit tried?
Mike Wilson
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- Ron LaDow
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Re: How many plugs would a combustion chamber plug if...
Mike, last I saw, John was reshaping the chamber but not altering the plug location. Got a link to something new?
I haven't spoken with John since the Lit Meet.
I haven't spoken with John since the Lit Meet.
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Re: How many plugs would a combustion chamber plug if...
John was reshaping the combustion chamber into a delta shape which corresponded to a custom piston. Perhaps he'll weigh in on any new developments.
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Re: How many plugs would a combustion chamber plug if...
Does it make power? Is it efficient? Does it behave nicely? If the complicated modification doesn't perform better than the simple modification then don't waste your money. Generally adding material or complex shapes the top of the piston is counterproductive because of additional reciprocating weight and because flame fronts don't like to change direction with the dome shape.
Think about 5 valve heads that Ferrari and Yamaha praised and endorsed for years. There were even a few development engines built with 6 valves. Four valves worked great so more must be better, right? WRONG! Ferrari and Yamaha used the 5 valve mystique to sell their products but meanwhile they were getting their asses kicked in motorsports by other manufacturers with 4 valve engines. Eventually they had to admit that simpler is better and they reverted to 4 valves.
Think about 5 valve heads that Ferrari and Yamaha praised and endorsed for years. There were even a few development engines built with 6 valves. Four valves worked great so more must be better, right? WRONG! Ferrari and Yamaha used the 5 valve mystique to sell their products but meanwhile they were getting their asses kicked in motorsports by other manufacturers with 4 valve engines. Eventually they had to admit that simpler is better and they reverted to 4 valves.
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Re: How many plugs would a combustion chamber plug if...
John does a lot of R & D on engines so hopefully he will weigh in to update us or one can visit his web site.
Mike Wilson
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Re: How many plugs would a combustion chamber plug if...
The only dyno that matters is the race track.
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Re: How many plugs would a combustion chamber plug if...
I had an Audi RS4 ten years ago with a V-8 and 5-valve heads. Seemed to work pretty well to me. When it snowed, it was a kick to turn off the traction control and get rooster tails at all 4 corners. Great car except for the steering feel.
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Re: How many plugs would a combustion chamber plug if...
How many plugs would a combustion chamber plug if IT COULD IGNITE AND BURN IT'S FUEL CHARGE MOST EFFICIENTLY? Two plugs is more efficient than one, and a dry sump is better than a belly full of oil resisting the inertia of the crankshafts ability to make torque. An air and oil cooled engine will live longer and perform quieter than if either were left on its own to extract heat from the kitchen. If Porsche left well enough alone, they'd still be building models 356D, 356E, 356F, 356G, 356H, 356I, 356J, 356K, 356L, 356M, 356N, 356O, 356P, 356Q, 356R, 356SS, 356T, 353566U, 356V, 356W, 356X, 356Y, 356ZZZZZZZZZZZZZZZZZ. Thank goodness Porsche skipped all that and went straight for the 911 and 912. Seems like Porsche history is beginning to repeat itself. Long live the four cylinder Porsche engines. Actually, any plugged engine Porsche chooses to build is a pretty damn good engine, even those with a few kinks left to sort out after initial production. This move towards electric motors, wouldn't the boss have been pleased to see this turn of events. Tooooo bad the EE's were finally let loose in the kitchen, this era of integrating computer management hardware with all the insane bells and whistles is boggling my gray matter. Just give me a Porsche without all the bells and whistles. Wahhhhhhhhhhhhhh! Love my 356 project.