Aloha,

I found a champian spark plug made for boats, it's a halo plug . Part # L76V  , has anyone tried using one.
I believe it is resistorless...

Mahalo Nui Loa

HV

COIL HEAT TESTS #1

Ok...here is some info about the heat of the coil upon use!

The temp on start of the coil is 99F
The temp on start of the plug is 98F

Both coil and plug were sitting in my un-air conditioned shop all day in the Florida heat 

The test is 5 mins long, stopping at one min intervals to take measurements.

120+ plasma fires per one min.

NO water was used during test except for some during the last min interval.

MIN              Coil Temp                        Plug Temp
1                    112                               100
2                    120                               102
3                    130                               106
4                    145                               110
5                    142                               108 <~~ I sprayed water on plug during this min!

More tests need to be made with water being sprayed all the time. And longer amounts of time.

Xbox,

Good to see you doing some temp. testing.. I wonder what the max temp will end up at ?
Are you still using the same coil? 

Quote from: happyvalley808 on July 21, 2008, 06:51:39 PM
Xbox,

Good to see you doing some temp. testing.. I wonder what the max temp will end up at ?
Are you still using the same coil? 

I think 150ish...

The first image is my coil that i have used in most of vids... the second image is the parts i used to make it. Its just a choke on a ferrite rod, then i wrapped a primary onto it using a some coil wire from a microwave transformer.

BTW...the gap on my plug is .060"  ... "The bigger the gap the bigger the snap!"TM 

@Xbox Which is your secondary ? Use thick copper wire for secondary , In Xbox image secondary wire looks very thin. It may not pass high current effectively and become hot.

Here is the simple circuit diagram of my 700Hz 250V AC inverter, It works great not much heating of Mosfet....
If you want to go for more high frequency you need to consider following points.
1. MOSFET diver is must.
2. Use ferrite core.
3. MOSFET gate capacitor..

in my engine test I am not using any inverter, Inverter turansformer is burned by mistake...

R2+VR1 and C2 gives you frequency
Freq=1/(5RC)