Hey guys,

My pop's Evo came with ARP head studs installed by the previous owner (at whichever shop he chose). From what I understand, they're the brand to go with for this. Unfortunately, on father's day, my dad and I went out for a drive and it seems that the head gasket failed.

We took the valve cover off and found that cylinder 1 had antifreeze in it. We looked some more and then when we were unbolting the head from the engine, we found that two of the nuts were cracked.

So we have a few questions for anyone who'd be willing to help out!

1) should we be going with ARP replacement nuts? Or is there another brand we should pick instead of ARP?

2) would anyone happen to know where we can get a head gasket for an Evo IX that has been bored out to... 2.3L? I have to double check that, but I think that's what it was haha

3) Can someone translate this torque info I found in the official torque specs thread? My dad was a mechanic for a bit over 30 years and he's never found instructions saying to torque down and then loosen it by 20 pounds...
Cylinder head and valves
Cylinder head bolt 78 ± 2 (58 ± 1 ft-lb) → back off → 20 ± 2 (15 ± 1 ft-lb) → 90° + 90°


Thanks so much for any help you guys can contribute!

Pics for clicks:

 

The engine wasn't bore out to a 2.3, it was stroked. So a standard head gasket is fine.

This is the first I've heard of an ARP fastener failure like this. It is possible the shop over torqued them.

I would just get a whole new set of ARP studs and nuts, and then install them per ARP's instructions.

 

if its a real arp nut, i have a hard time believing one, let alone two, cracked. arp is no joke when it comes to qc.
early chinese/ebay studs ive seen break. wouldnt be surprised to see one of those nuts crack.
also, with arp studs you follow their torque specs, not the factory stuff. just like with factory bolts you follow factory specs not arp specs. sometimes old mechanics are worse than someone thats never done it before but bothered to fully read the instructions.

 

^^^ This, Somethings not rt, cant see ARP failing especially the nuts? Not sure where the back off 20ftibs come from, old school would be to retorque--but that's not what we have here.