blowing o-rings

[Gixer1460]

13 hours ago, Baron said:

I'm also going to put APE studs on mine, where can you get those hardened washers?

Fred's requirements are somewhat more 'extreme' compared to even a high spec engine - standard washers are more than adequate for majority of builds! If you can / are building enough boost / cylinder pressure that head lifting is an issue then i'd also be looking at upping the stud diameters as is common with Busa engines - std. 10mm waisted studs / bolts upto 12mm straight sided and even 13mm for extreme use, all HT 12.9 quality bolts and 120-130 ftlb torque