I just went to harlands website and checked out what they had for AFR 185 heads. sure enough they are 1:6 harlands, the way they cnc the rocker is very distinct and the way you i.d. the ratio was right on the money with the harland website. I emailed tech support and told them I would send them all in. so they sould figure out why one failed so quickly and the others look brand new. I hope this works and I can get to the bottom of this quickly thanks for the help guys jessie