slparry wrote:https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=6&Q=ELA01261&x=0&y=0
seems a bit far fetched to me, what do you reckon people?
dyno.jpg
Initially, I like the basic idea, 'cos it's outside-the-the-box thinking applied an established design principle.
100 yrs ago, ppl suspected that the intake charge may not have finished burning before the exh valve opened.
Situation worsened with the advent of alloy pistons (= rise in rpm), so twin plugs were introduced, with the idea that if the fire was lit in two places, more of the fuel would be burned during that time period. Ahem koff koff ... how quaint ...
Off The Top Of My Head, (OTTOMH), there was a 1930's Nash, and fairly sure an Italian engine mob used it in the '20s.
https://en.wikipedia.org/wiki/Dual_ignitionBut at the heart of the problem was 'swirl'. Ffwd to early '60's: Honda fitted a quartz glass window to the side of a cylinder and took slo-mo movies of the combustion process. Saw that much of the charge was not being ignited 'in time' because it was not being reached by the flame front. Realised they could swirl the intake flow by way of changes to intake valve angle, squish band, shape of piston crown, and get the flame front in contact with much more of the charge.
For those familiar with the original CB750-Four head, there is a small ridge existing between the valve seats. It assists with swirl production.
4 valve heads brought a new problem: symmetrical valve layout and combustion chamber shape = worse swirl. Yes - got sort of an offset viz better high rpm power, but with less efficient combustion. Lots of research papers on this.
One solution: my Porsche 928 S4: for years, tuners/porters etc moaning about detonation limiting power gains.
From left field: cam designer decides to slightly retard the opening of one inlet valve, so as to have the other produce a momentary spray-nozzle effect, to stir the pot, as it were, before the second valve opened.
Result: OTTMH, +60-70 hp, with several degrees fewer spark advance. (From a 320hp base).
On to the Jet Spark idea: in the mid-late '70's, Honda built the CVCC engine: Compound Vortex Controlled Combustion. Used a small additional combustion fed with very lean mixture. Lean mixture burned for longer, igniting swirling mixture = cleaner burn = lower emissions without use of cats. (mmreeeeowwww).
(BTW: Mr Honda wanted to corner the market with this innovation, but faced an executive/staff revolt: this innovation would improve global air quality / health for all ppl, therefore Honda San, we cannot capitalise upon it as we would our other market innovations. Honda licenced the patent for worldwide use This marked the decline of Sochiro Honda's authority within the company).See where this idea is coming from, and why I think it has legs?
It produces both swirl and multiple ignition locations.
Another of those
'left field' ideas from a bloke doing a pit of pondering and 'thunking' in the back of his workshop.
For me here in Oz: 50 quid ex UK vat. Translates to AUD$100. For only ONE.! Cranky consumer in me ... grrrr.
But ... being logical about it ... if it works as advertised ... at $20/week for fuel, two would pay for themselves in the first year.
Vewy vewy tempted. Does Motorworks have a refund policy on these?
Real torque curves don't have a first derivative. :-^)
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