I've had some driveablity problems with me 1JZ since being back on the road. Some sputtering and popping going up through the rev's when boosting hard. Seems to smooth out in 4th and 5th gear when not mashing it down. Pulled off the coil packs, and took off all the rubber boots, and discovered some pretty ugly fractures on all but one of the stems. I've read here before that some folks have epoxied them, and it worked well. I have both high grade, two part epoxy, and JB Weld. Which one would work better, and do you think that this is one of my issues with the poor performance of my engine?