Oh dont worry i KNOW what caused my failures!!!!!..It was taking advice from a certain tuner who claims its ok to run std head bolts on a T4 running 34psi held!!!
HOWEVER...as i have said...and what you kinda posted Rob...they have to be machined in correctly and installed correctly....which i beleive mine were as they lasted fine until i cranked the boost up....and got a cracked block around the middle six bolt holes for my trouble which kinda proves head lift.
Ryan you would big them up seeing as your trying to flog a copper rung block!...Incidentally i paid £175 for my ringed RS500 plant pot with new liners ready for pistons.