Spark Gap Calculator

Hello guys,
I'm new to this forum. I have posted a link above, post which determines breakdown voltage required @ spark plug tip. I just wanted to know which formula have the used to determine the same. Any help would be great.

voltage.value = Math.round((4.3+136*((pressure.value/101.3)/(temperature.value*1+273))+324*((pressure.value/101.3)/(temperature.value*1+273)*(gap.value*25.4)))*1000)

This is what i got from the page source. Please tell me what factors are 4.3,136 and 324

thank you in advance

 

What are you trying to accomplish? RX-8 plugs come pre gapped.

 

If you're asking just to ask, Charles has your answer, but 9k is right, our 8 plugs are the exact gap they need to be right out of the box, best not to mess with them, you arnt going to optimize anything, just cause yourself issues.

 

I want to have a generic equation to calculate required gap, w.r.t to parameters like dynamic pressure, compression ratio, temperature, and other parameters if any. I'm not just asking , im a student/intern working on hardware and on some documentation on optimization of engines.

 

The 101.3 is a constant from chemical engineering equations - essentially used to convert from kiloPascals (pressure in SI units) to other units. So there are 14.696 psi (lbs/in2) in 101.325 kPa also written as 14.696 psi/101.325 kPa. For those in the UK the conversion for using bars of pressure is 1.01325 bar = 101.325 kPa pressure.

273 is the conversion from temperature in Celsius (°C) to degrees Kelvin (°K): C + 273 = K. Kelvin is used often in scientific applications since 0 degrees Kelvin is absolute zero (where no molecular motion exists).

 

25.4 is mm to inch conversion

 

Any idea on these values in the above equation (factors 4.3,136 and 324)