Hi, I've used Brisk plugs in a turbo'd 451 and am currently running Brisk plugs in two stock 451's and a supercharged Polaris Slingshot (Vortech V3 SC, 11# boost depending on exhaust setup)... #1
, for any modded app, you typically need to use a colder heat range just as with a conventional side gapped race plug. If you can't find the right heat range with the Brisk brand, you can typically find them with Autolite, but without fancy silver electrodes... #2
, you can't just install these and forget 'em. Like a typical old-school plug, I pull these and check/adjust gaps every 15K to 20K miles or so. I've never had a Brisk plug go bad -- but I took care to use non-projected nose plugs in colder heat ranges and inspected them. As for the 451 coil pack bolts snapping -- I typically use anti-seize on anything going into aluminum and haven't had any issues with these yet (but, now you've got me thinking about replacing these bolts with ARP SS bolts -- isn't OCD great?). I also use anti-seize on wheel nuts/bolts (not dissimilar metals into aluminum, but these often get rusty and stubborn).
I've found non-projected nose Brisk plugs to work well with Pee-Pee Kalifornia gas. Eliminated most all of the ping rattles in the 451 -- those which are audible anyway (unfortunately not all detonation is audible). These worked well in the turbo'd Smart -- and work well in the SC Polaris Slingshot (two heat ranges colder -- tossed the Iridiotium plugs supplied by the SC kit manufacturer). Kalifornia gas is nasty. There was a time you could go to Home Depot and get cheap toluene by the gallon and use that as an octane booster -- but I've only seen that in useless pint sized cans lately, if you can find it at all... Out of all of the premium gas brands I've tried, 76 currently seems to be the best -- but, your mileage may vary (sic.).
No, I'm not any salesman. Used to be an engineer, now I'm a statistician/number cruncher programmer analyst (I think headhunters call this Data Engineering nowadays). Love the Smart cars. Easy to park and two of them take up only 1 garage space (parked nose to tail). But, the Polaris Slingshot is considered a motorcycle that can use commuter/HOV lanes at any time (passenger or not) -- so that is currently getting the most use even on cold days...