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Thanks for the posts/replies? I am now ,far less ignoant.

I few questions on the posts though:

-What is R/inches? Is R from the head of the valve to the beginning of the intake system , the inside lid of the air cleaner; Distance per R? I think I got it. R = restriction from vacuum?

-What is harmonic peak in reference to induction systems?Is it related to reversion? How about 1st 2nd and 3rd harmonics? What is the sencond and third?

Thanks for your expertise!

The resonance provides a supercharging effect, can be quite significant.
A well proportioned plenum (or airbox, same thing, really) can increase the effect.

http://lmgtfy.com/?q=intake+runner+harmonics
http://lmgtfy.com/?q=helmholtz+resonator


The primary (1st)resonance is strongest, the higher multiples decrease significantly, second or third are typically used due to packaging/reality.
The runner diameter on primary resonance also tends to have to be ~huge due to friction losses, second/third work out better for diameter as well.

Exhaust tuning works almost the same way but to create an effective vacuum, the gas temperature has a huge effect on tuning, as that is what determines the speed of sound in a gas.
http://lmgtfy.com/?q=speed+of+sound+in+a+gas

Rudolph Diesel's first engine was a direct injection/injected engine that used peanut oil as fuel. The Diesel was a compression ignition engine.