We run the Taylors on all our cars.I even have them on the Harleys.If you pulled an end off they were defective or you pulled awful hard.The ones on my 440 have been on at least 10 years with big tube headers and Ive had them off probally 60 times.Never pulled a boot off.That and they still fire like the day I put them on.Have and had them on at least 6 Mopars with headers.Did you use the diaelectric grease that comes with them?Ill replace mine next year as they are looking pretty old after all these years.Ill still save the old ones though.Rocky