right part number for arp head studs

4203's are SII studs.

123-4203 (12pt studs) are listed for stock head 109(86-87)
223-4203 (12 pt studs) are listed for stage2 14bolt head

bolts for stock heads on a 86-87block
123-3603 head bolts - high perf series -hex head
123-3703 head bolts -high perf series-12pt head
223-3703 head bolts -pro series - 12pt head

studs for stock heads on 86-87 block
123-4003 head studs - pro series - hex head
223-4203 head studs - pro series -12pt head

223-4204 are 12pt studs for champion alum heads on 86-87 block
While were on topic, anyone have the part numbers for the 84-85 blocks. Thanks!

for blocks (77-85) with stock heads
123-3601 head bolts high perf hex head
123-3701 head bolts high perf 12pt head

423-3601 stainless head bolts hex head
423-3701 stainles head bolts 12pt head

123-4001 head studs -pro series - hex nuts
123-4201 head studs - pro series - 12pt nuts
OK, whatever. Here's their site, noticed circled data.

It came out pretty small. If you can't read it, it says "Buick V6 Stage ll Champion head stud kit"


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jegs online catalog needs some work
i use summit for looking up parts as they have an easier to navigate catalog and better descriptions , they also used to have the products install/tech manuals for download
arp studs

A while back I purchased a set of M&A stageIII heads for a stage motor. It was a complete kit, rockers,guide plates, etc. I would like to change out the head bolts tr studs. Do you have the part# for this combo? It's probably the same 14 bolt set like the champions? What's better-hex head or 12 point? thanks