Author Topic: Lets understand the advance in spark  (Read 2186 times)

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Lets understand the advance in spark
« on: July 28, 2016, 02:43:16 am »
well in the last two weeks i have played a lot with my bicicle with 4t stroke motor... i´m going to work everyday with it now and i´m saving some money on gasoline... 

i found that this motor is one cilinder around 48cc and has a compression ratio of 6:1

and the recent studies i made i have learned about the advance on spark ignition and fuel mixture burning speed...

i found some slow motion transparent motor making a good picture of what is all about..

basically the spark does not occur at the tdc point it rather is advanced happening before the tdc because the fuel is not prety fast enough to burn and create maximum pressure at the high point of the piston... this is where the higher efficiency lies on...

so before the piston reaCH the tdc point or the maximum compression the spark happens... from 12degres at idling and up to 30 degrees before tdc at acceleration

distributors have mecanical or hidraulic means to create this advance according to rpm



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Re: Lets understand the advance in spark
« Reply #1 on: July 28, 2016, 02:51:06 am »
the faster burn rate of hydrogen at stochiometric ratios may not be the same speed when the gas is mixed with ambient gases prior to gas combustion...

hydrogen can burn in a oxgen atmosphere up to 4% concentration (from books) like wise the oxigen would burn in a hydrogen atomsphere at the same ratio

at lower concentration than this it just wont fire.. 

i found a good manual on hydrogen substitution for combustion engines and its problems i posted it somewhere here..

so lets do some calculations...

50cc motor needs how much hydrogen?

if we consider maybe 10% to be sure it will burn than 5cc of hydrogen must be injected per combustion cycle... the rest will be air composed of 78% nitrogen  16% oxigen and some other rare gases

if we were to consume all the 8cc of oxygen in the cylinder with hydrogen than it would take twice as much as hydrogen than oxygen to be injected but the problem is that hydrogen ocuppies a lot of spaCE being a gas so injecting hydrogen mean inject less air and therefore less oxygen


how do we find this equilibrium?


the paper in atachment made all the hard part thru

« Last Edit: July 28, 2016, 03:11:40 am by sebosfato »

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Re: Lets understand the advance in spark
« Reply #2 on: July 28, 2016, 20:08:21 pm »
today a friend lended to me a strobo light that takes the signal from the spark plug and generate a flash such for looking at the advance in spark

it allowed me to observe that in my car the spark is advanced when acccelerating and when rpm is high

it seems to me that as we accelerate the injector not only has to send more gasoline but also it advances or retard the spark according to the states

low rpm normal advance may 10 degress

(acceleration (no vaccum) and high rpm more advance  maybe 40 degrees..

theoreticaly the car central should be set to give the best conditions based on the rpm reading the map sensor and the lambda sensor...

i was wondering if adding hho to the car will be able to change this firing angle automatically... as it will feel more complete combustion the lambda sensor will certainly make send less fuel but i guess the timing is more like a scale that is used for the advance..



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Re: Lets understand the advance in spark
« Reply #3 on: July 28, 2016, 22:36:53 pm »
remembering there is also the catalytic converter , oxy sensors and air injection.

I watched Steve Ryan 60 minutes video a while back .   the scientist said the exhaust reading of his hydrogen bike was thesame as a normal petrol car .
what the scientist or 60 minutes did not say is that you can not compare a car engine with a catalytic converter to a 2 cylinder bike without a catalytic converter .
it should be expected to have unburnt engine oil in the bikes exhaust reading

the catalytic converter is expected to chemically convert co into co2 at the same rate that the engine functions (in millions of vehicles)  yet it seems inpossible that steve ryan can convert H2O in 20 minutes into a new liquid ...... on 1 vehicle .

his invention was never revealed and no one any where has been able to discredit his invention

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Re: Lets understand the advance in spark
« Reply #4 on: July 28, 2016, 22:45:27 pm »
Yes that is pretty much correct...

the lambda sensor for the combustion completeness thru reading of available oxigen however goes before the catalytic converter...

the lambda sensor works creating a potential diference between two electrodes situated at regions with different concentration of oxigen,

the catalytic converter also burn hydrocarbons that didn't burned up inside the engine too...

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« Last Edit: July 29, 2016, 04:00:07 am by sebosfato »