ARP Head studs

[syrushcw]

So I lost a bolt and washer for one of my head studs I see on extremepsi the sell them they offer 11mm and 12mm, but I was fairly confident mine were 13mm can some one correct me on this?

 

[blcknspo0ln]

Our studs are either 11mm or 12mm, the socket you use is a 12-point 13mm. Are you 6 or 7 bolt'd?

 

[99gst_racer]

6-bolt block = 12mm
7-bolt block = 11mm

 

[syrushcw]

7 bolt