What spark plug

Information relating to the Matchless G3 or AJS Model 16 350cc Heavyweight
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Pharisee
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Re: What spark plug

Post by Pharisee »

Taid wrote: Thu Sep 08, 2022 5:48 pm It seems it is now called 'pre-chamber' ignition .. a separate small chamber has the spark plug and when ignited flames pass through small holes into the main combustion chamber, rapidly igniting the fuel mix in there .. Maserati and Honda are playing with it and some F1 engines have it ..

Can't find any reference to what I may have been reading those years ago ..
Honda used it on one of their small cars a few decades ago in an attempt to reduce emissions and improve the mpg, I can't remember the model of the car, but I remember seeing one in pieces on "Wheeler Dealers" a while ago.
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SPRIDDLER
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Re: What spark plug

Post by SPRIDDLER »

Harry Ricardo, one of my engineer heroes, covers cylinder head design and its effect upon the spread and speed of the ignition flame front and in Chapters 2 and 4 in his wonderful book from the 1920's: 'The High Speed Internal Combustion Engine' he analyses in academic, practical and experimental detail the effect of spark plug positioning and combustion chamber design. In particular the benefits and drawbacks of a separate and small primary compression space housing the spark plug where the first and 'early' flame of ignition rapidly increases pressure in that confined space which forces the flame to exit at accelerated speed into the main fuel/air mixture in the larger main combustion area.

That's my very inadequate and brief amateur interpretation of his extensive writing on engine design and if so inclined you can read all 430 pages of his fascinating book in Christians Archive here:


http://archives.jampot.dk/book/Workshop ... o_1931.pdf


I'm not really a nerd but it is my second favourite and frequently re-read book after 'The Wind in the Willows'. ;)
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g80csp11
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Re: What spark plug

Post by g80csp11 »

Harry Ricardo was a true engineer, who died on 18th May 1974. I didn't start at Ricardo until 1980 but had a fantastic 40 years at Ricardo in Shoreham by sea . I remember running a E6 variable compression engine where you could vary compression , AFR all on the fly , In later years we used this engine as part of the graduate training scheme , any eye opener to young engineers that often had no idea of real engineering but knew the theory !

I was also part of Diesel and Gasoline engine development projects plus many more prototype engine projects over the years in the UK and across the world. Great times
Ricardo E6.jpg
U tube clip talks about the development of the RR Crecy engine , showing what a genius Harry was , I only wish id met him

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Taid
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Re: What spark plug

Post by Taid »

Thank you for publishing this video

The type of engine I was trying to recall is 'stratified' as mentioned in the video. .. I had forgotten the exact detail,
Last edited by Taid on Fri Sep 09, 2022 11:24 am, edited 1 time in total.
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Re: What spark plug

Post by Groily »

THAT video was amazing! Never seen it before - thanks for posting.
Sleeve valve Daimlers, yes, but I had no idea the concept could potentially have been so much more powerful than comparable or much larger 4 strokes. Really really interesting.
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