I am in the process of putting a trick flow stage 1 cam in my 94 cobra. I am going to run my gt40 heads and would like to keep my 1.7 rockers. I have a friend that has a set of the tfs 2500100 spring kits for factory iron heads that has never been out of the box he said he would sell me for $80. I have seen 1 post on corral about someone having problems with the retainers mushrooming out in 8000 miles didn't know what your opinions are on these springs? ........thanks Jeff