Autolite 3933x: Any1 has run this plug?
 

I've come across discussions on the 3932x but not the 33x.

I believe the 33x is 1 step "hotter" plug.

I have a set on hand. The electrode sticks out a bit further out than the 32x.

Is the electrode dangerously close to the Apex seal?

i ran them briefly but started to have misfires around 500. since the ground straps are not adjustable we weren't able to close the gap. we moved on to the 3932. also, the 33x and 32s are non resistor so the chances are good the elec interference will lock your ecu.

highly recommend to everyone that you pony up and buy the right plugs which are around $30 per... the one plus is they last a long time.

for part numbers see the "Tuning Ignition Section" of my site: TUNING/ IGNITION

In addition to what is on Howard's site, despite what a bunch of window lickers advocating copper plugs on boosted engines in Facebook groups would have you believe, basic electrical field theory and large scale HV testing correlates with the findings of anyone who has been methodical with in service or pressure chamber testing with plugs. The fine iridium tips cause a greater field gradient around the electrode for the same supply voltage, allowing charge breakdown at higher pressure. This is why HV test labs run large domed stands on the towers and wrap internal building infrastructure with large radius shielding if they are getting breakdown to points which aren't intended. Watching a couple of million volt spark over is quite interesting.

Slides, would you please entertain my laziness and elaborate on...
" ...allowing charge breakdown at higher pressure."

Still trying to get a handle on the impact of electrode material performance on boost and fuel type.

Due to the much higher melting point and hardness of the iridium it can have a much finer/sharper tip, this creates a greater intensity in field for the same electrode to electrode voltage. Looks like there are a fair few understandable resources if you google it.

Thank you for the feedback...