« Reply #23 on: Sep 21, 2021, 11:27 am »
For those who enjoy reading about over-complicated Twin-Spark engines;

« Reply #22 on: Sep 21, 2021, 10:14 am »
Years ago I fitted a separate lift engine to my cruising KESTREL ( a stretched Osprey) with a reliant robin thrust.
The lift was a two plug, two stroke. Noisy and hard to start. It needed winding up and sit back whilst the thing awoke slowly from a doze.
Eventuellerie I disconnected one of the wires feeding the dual system as it "looked" as if the energy was being halved and put thro two coils etc.
This re-routed ALL the power and cured the poor starting issue and I sold it 5 years later running on all the power thro ONE coil to one plug.
Crummy system or what?
All twin systems I know (aero engines etc) have two separate STAND ALONE systems to obviously allow for one system going down but allowing you to continue and avoid the "crashy thing", Redundancy is very good when your hover height is measured in thousands of feet!

Memories are BETTER than Dreams---"Capn" FLINT

« Reply #21 on: Sep 20, 2021, 9:53 pm »
Back to the two plug thing, I dont think there are many two plug engines around that didn't switch to single plug after a while. eg BMW R's. Unlike John's Mazda my 48 year old engine has single plugs :P :D

« Reply #20 on: Sep 20, 2021, 7:05 am »
I am disappointed Steve  :'( :'(  but I think I (and you for that matter) will live
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« Reply #19 on: Sep 19, 2021, 9:05 pm »
Every cloud Nick :-)

Gaz, it's probably safer I just build a larger craft, not as dramatic as the effects of fitting a pulse jet to a Vanguard.....The idea of a vectorable jet turbine assist has passed through my mind, fortunately it was just a passing thought!
There's no such thing as bad weather, you're just wearing the wrong jacket!!

« Reply #18 on: Sep 19, 2021, 10:29 am »
At least all noise from the lift fan would be lost.  ::) 
Can ears ACTUALLY bleed?🤦🏻‍♂️
Memories are BETTER than Dreams---"Capn" FLINT

« Reply #17 on: Sep 19, 2021, 6:24 am »
an actual pulse jet engine on the back of the Vanguard

I'd pay to see that lol
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« Reply #16 on: Sep 18, 2021, 9:48 pm »
That would indeed be impressive! Years ago I had a mate who had an experimental pulse jet “liberated” from a factory in Coventry. It could be started with the aid of two blow lamps and petrol poured in neat. The flame was impressive- 6 feet out the back - and the noise more so. All in a wooden shed. They were the days!!!
Ian Brooks
Gloucester, UK

« Reply #15 on: Sep 18, 2021, 6:24 pm »
I'm starting to think an actual pulse jet engine on the back of the Vanguard would make it go faster and keep up with everyone else...............What could possibly go wrong............Answers on a postcard to .......
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« Reply #14 on: Sep 18, 2021, 1:06 pm »
An extract about Twin Spark Ignition systems
A dual ignition system will typically provide that each cylinder has twin spark plugs, and that the engine will have at least two ignition circuits, such as duplicate magnetos or ignition coils.[/size][3][/size][/font]
[/size]Dual ignition promotes engine efficiency by initiating twin flame fronts, giving faster and more complete burning and thereby increasing power.[4][/size] Although a dual ignition system is a method of achieving optimum combustion and better fuel consumption, it remains rare in cars and motorcycles because of difficulties in siting the second plug within the cylinder head (thus, many dual ignition systems found on production automobiles typically were of a two valve design rather than a four valve). The Nash Ambassador for 1932-1948 used twin sparkplugs on the straight eight engine, while later Alfa Romeo Twin Spark cars use dual ignition, as do Honda cars with the i-DSI series engines, and Chrysler's Modern Hemi engine.[/size][5][/size] In 1980 Nissan installed twin sparkplugs on the Nissan NAPS-Z engine, with Ford introducing it on the 1989 Ford Ranger and 1991 Ford Mustang four-cylinder models. Several modern Mercedes-Benz engines also have two spark plugs per cylinder, such as the M112 and M113 engines. Some motorcycles, such as the Honda VT500 and the Ducati Multistrada, also have dual ignition.[/size][6][/size] The 2012 Ducati Multistrada was upgraded with "twin-plug cylinder heads for smoother, more efficient combustion", the change contributing to a 5% increase in torque and a 10% improvement in fuel consumption.[/size][7][/size] Early BMW R1100S bikes had a single spark plug per cylinder, but after 2003 they were upgraded to dual ignition to meet emission law requirements.[/size][/font]

« Reply #13 on: Sep 18, 2021, 7:42 am »
Car manufacturers are doing things because they can, not because it’s better……and the public go for it.

NO  :o .
Car Manufacturers do these things because it makes them money  ;)  by making it more complex it cuts out the amateur mechanic. Now you HAVE to take your car to a stealership for repair rather than fix it yourself = more revenue for the stealerships branded garage. Heck even local garages have trouble fixing the damn things because so much specialised kit is now required for each brand. Add in more expensive parts = more revenue for the manufacturer, win win for them, loose loose for us!

Had a high level brake light go on a Ford Galaxy once, HAD to go to the stealership as no user serviceable parts  :o  For a lightbulb?  :-X
« Last Edit: Sep 18, 2021, 7:47 am by Gaz »
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« Reply #12 on: Sep 17, 2021, 9:02 pm »
My motorcycle has two plugs for the reason below, nothing to do with making it super duper.

'Usually 2 plugs are used because of poor combustion chamber design and is employed as a compromise, to help the fuel/air mixture ignite more completely. Hemispherical heads commonly use this because, although they can be made to produce a lot of power, because of improved airflow through the valves due to the canted valves / valve placement, they are not always the most efficient design. If the valves aren’t spaced far enough apart in the center, a plug cannot fit where it ideally needs to go, so they put 2 plugs - one on each side - to mitigate the bad / compromised chamber design.'
There's no such thing as bad weather, you're just wearing the wrong jacket!!

« Reply #11 on: Sep 17, 2021, 7:17 pm »
I've got an old car so no experience of them modern things!  I suspect it's part of the "disconnect-the-driver" move towards self-driving mass transport (it's been underway for years - almost none of the controls in a modern car are connected to whatever the control!).

I looked at the pulse jet thingy but it fell apart at the first hurdle - which is how the 1% "pulse" charge gets into the adapter thingy in the first place?  Igniting diesel (or anything that'll explode) has all been done before so I'm not sure what's really going on here - if anything.

On the twin plug thing I find it hard to understand why it would make any difference - it's like using two matches instead of one to start a fire, it won't change how much heat you get out of the fire and, even outside an an engine, as most know it's not exactly difficult to ignite a air/fuel mixture and produce an explosion!

Modern EFI engines don't expel unburnt fuel - it simply can't happen so again, I don't understand how you could make it "burn better".  If you are burning all the fuel all of the time where does this new extra energy come from?  Making the explosion happen slower would probably be an advantage as it's be easier to extract all the energy from the expanding gas (back to the Atkinson cycle again!).

« Reply #10 on: Sep 17, 2021, 2:24 pm »

I quite like Electronic hand-brakes for hill starts!! It releases automatically when accelerator is depressed Or maybe I'm just lazy!!!
Not sure about key-less entry but I do like the keyless ignition-- just press the button!!!

Has anyone looked at the Scriminger face book page yet? Quite interesting

Ref twin plug ignition systems I used to fly in a friends fixed wing Micro-Light powered by a twin cylinder Rotax and when checking prior to a flight the engine revs always dropped when one ignition system was switched off, so twin plugs must burn better?
« Last Edit: Sep 17, 2021, 2:32 pm by Warby »

« Reply #9 on: Sep 17, 2021, 1:42 pm »
Tempted as I am to go off Al's original post, I suspect the twin plug design is engineering rather than sales oriented, Suzuki are a budget brand cost is everything even at the penny level, their other engines usually only have one plug.
There's no such thing as bad weather, you're just wearing the wrong jacket!!