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Old 08-16-2014, 01:10 AM   #15 (permalink)
Frank Lee
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Personally I'm not real interested in trying it. I have a supercharged vehicle that is supposed to have premium but I've had no problems running it on ethanol blends (ethanol LOVES compression, static or forced). If it did have any issues I'd simply run a stronger ethanol blend or next, try the next colder heat range plugs.

I'd also be nervous if trying this with aluminum heads as the threads in the head are fragile enough the way it is; I'd use less than the recommended torque on modded plugs as these and be darned careful the plug's threads don't damage the head's threads due to any "hangnails". Also it may be prudent to simply R&R modded plugs more often because there is going to be an exposed section of plug hole threads that may carbon up or otherwise want to trap the plug in.

In spite of the minor cc increase and corresponding minor C.R. drop, this mod exposes sharp edges to the chamber that wouldn't be there otherwise; seems to me that could increase detonation. And I wonder if such a recessed pocket is a hindrance to good combustion chamber geometry- like the old-time engines that had pre-chambers. Pre-chambers are all but extinct now.

Or maybe I'm just over-thinking it all.

Last edited by Frank Lee; 08-16-2014 at 03:22 AM..
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