Head Bolt/Stud Options?


  • Head Bolt/Stud Options?

    To use with a conventional type head gasket, no O rings. Looking at the number of bolts per head I'm thinking ARP prices should not be necessary, studs may be better if the heads can be removed with the engine still incar.

    So what are the recommended options for say 500 WHP? Don't want to be marginal with this but don't want to waste money either. Then again I bet the OE bolts are not cheap.

  • #2
    From my experience oem bolts work great to 500-550 after that i'd advise arp studs. If you search this section for arp you will find the arp info.
    Praying....

  • #3
    1SickZ wrote: From my experience oem bolts work great to 500-550 after that i'd advise arp studs. If you search this section for arp you will find the arp info.
    firefox wrote:
    we got 13 per side. 4.333 per cylinder

    for a comparision
    a small block chevy v8 has 17per side. thats 4.25 per cylinder





    i think oem will be good for almost anything.
    Think, or someone with experience?
    - VG30DET (HE341) 86 300ZX - 1982 280ZX Turbo - Headered NA 1986 300ZX 2+2 - 2000 Xterra -

  • #4
    firefox wrote: we got 13 per side. 4.333 per cylinder

    for a comparision
    a small block chevy v8 has 17per side. thats 4.25 per cylinder





    i think oem will be good for almost anything.
    That doesn't mean anything.

  • #5
    I know some people are running around 450 rwhp with OEM head bolts. Might as well just run ARP and not have to worry about it at your power level goals.
    Usual Z31 suspect: Garage Queen (aka broken)

  • #6
    Thanks to all who contributed, looks like a set of ARP from Z31parts would be the way to go.

  • #7
    I blew OEM gaskets with OEM bolts torqued to factory specs somewhere around 550whp also. That is with an O-ringed block.
    85 Z31 6.0 LSX turbo 766whp/792wtq
    04 GTO, LS6, big cam, porting, N20… underway for summertime daily driver.