Has any one else had problems with this locks? I have 04 z06 cam with Pro Magnum 1.85s. I broken a total of 5 poly locks( on the dyno, on the street, and lastnight at the track). I called comp and they said they have had no problems with these, that i was over tighting then. I,m a GM mechanic and had several small blocks and big blocks and and never had this problem. I understand that under factory V/C you cannot have as much material in the nuts but I have to find a happy medium. Any suggestions.

 

You breaking the polylock or stud? If so, are you installing the polylock on the flatter side of the rocker trunion?

 

^^++I have the same locks and lifters and I have no issues I would think has a point. My cousin who also works for GM here in town gave me the same advise, to not install the polylock on the flatter side because they could crack and brake. Now I know he was right!

 

I'm breaking the nut off the top. The allen set screw is in the middle of the break. And it does not happen when I tighten the down, It takes a little while. The poly lock is designed to sit on the flat side of the rocker ( common sence). I think it is just weak material.

 

It can happen bro I mean there is always a bad batch of anything, get new ones and see what happens. If they break again then go with something else but the only thing I can think of is a bad batch or material and it got through.

Good luck!