Hi I have the 351 windsor and I had a question about the spark plugs. I have a edelbrock 4 barrel carb on a powerplus intake, I also have new bbk shorty headers. I was just wondering if it is better to use a cooler spark plug with those kinds of upgrades to the engine. I have been using hotter ones. I read somewhere that if the plugs are the wrong temperature they can cause premature firing and also cause backfiring. If somewhat could clear this up for me that would be great, Thanks.