Has anyone else tried the odonnell 97t plugs, my motor ran decent with these plugs but seemed a little hard to start and cold natured. Could this be because of the97t plug, also i got 9:20 min. a tank on a dusty slick track, they hadn't watered that day using a 7.5mm restrictor, could the p5 get better fuel milage or should i go to a 7mm restrictor. I have ordered some p5's to try out next race. Thanks for any info....