z32 NA wiseco pistons in a z31 turbo application?

  • 300zxtproject
    300zxtproject
    Member
    • 39

    z32 NA wiseco pistons in a z31 turbo application?

    hello there i was in the process of rebuilding my z31 turbo with NA (9:1 CR) but i just found out i need new rods (bent) and i was looking at the z32 wiseco pistons with the eagle rods but i want to retain the higher compression to have some more lower end torque, so my question would the NA pistons (10.5:1 CR in the z32 so that equals 9.5:1 CR in the z31) hold up to about 14-16 psi and about 7,000 rpm redline? many people have said that the NA (z31) pistons would hold up well over 350 whp so would .5 more CR make a BIG difference? thanks
  • brewster240
    brewster240
    Senior Member
    • 150

    #2
    should be fine.

    unless there is some design flaw im unaware of?


    good tune is crucial.
  • 1SickZ
    1SickZ
    Senior Member
    • 634

    #3
    300zxtproject wrote: so my question would the NA pistons (10.5:1 CR in the z32 so that equals 9.5:1 CR in the z31) hold up to about 14-16 psi and about 7,000 rpm redline? many people have said that the NA (z31) pistons would hold up well over 350 whp so would .5 more CR make a BIG difference? thanks
    Yes it makes a BIG difference because it is a domed piston.

    9:5


    Versus

    10:5


    Your valves won't be happy.
    Praying....
  • 300zxtproject
    300zxtproject
    Member
    • 39

    #4
    [quote]1SickZ wrote:
    Originally posted by 300zxtproject
    so my question would the NA pistons (10.5:1 CR in the z32 so that equals 9.5:1 CR in the z31) hold up to about 14-16 psi and about 7,000 rpm redline? many people have said that the NA (z31) pistons would hold up well over 350 whp so would .5 more CR make a BIG difference? thanks
    Yes it makes a BIG difference because it is a domed piston.

    9:5


    Versus

    10:5


    Your valves won't be happy.
    oh wow… i didn't know that the NA pistons have the dome design. thanks

    so does anyone know of some good aftermarket pistons with custom CR for the z31?
  • 1SickZ
    1SickZ
    Senior Member
    • 634

    #5
    BRC
    Praying....
  • 300zxtproject
    300zxtproject
    Member
    • 39

    #6
    thanks 1SickZ. i called BRC and the have both 8.5/1 (dish) or 9.2/1 CR (flat) pistons and they also have some connecting rods to go with them for only 360 for the set of rods.... not bad at all. so i guess i'll go with them. 1SickZ, you don't happen to have any pictures of you pistons and/or rods, do you? thanks
  • 300zxtproject
    300zxtproject
    Member
    • 39

    #7
    Does anyone know if the BRC rods would fit STOCK w-series z31 pistons? i need some new rods and i want to keep the 9:1 NA CR. thanks
  • Kennedy
    Kennedy
    Senior Member
    • 1158

    #8
    300zxtproject wrote: Does anyone know if the BRC rods would fit STOCK w-series z31 pistons? i need some new rods and i want to keep the 9:1 NA CR. thanks
    BRC makes custom parts.. so they will fit if you ask them to make one that fit.
    Jukka Kivinen - Europe / Finland - '88 Turbo 2+2 Targa
    Datsun Nissan Sports Cars of Finland
    http://www.z31turbo.com / http://www.z31na.com
  • 300zxtproject
    300zxtproject
    Member
    • 39

    #9
    ok now i know that the NA wiseco pistons won't fit due to the dome design that they have. so does any other company make flat or dished pistons (besides BRC) for the NA z32 that will fit a Z31? i would really like to have 9.5:1 CR or at least 9:1 with some forged aftermarket pistons. thanks
  • SATAN
    SATAN
    Senior Member
    • 6782

    #10
    300zxtproject wrote: ok now i know that the NA wiseco pistons won't fit due to the dome design that they have. so does any other company make flat or dished pistons (besides BRC) for the NA z32 that will fit a Z31? i would really like to have 9.5:1 CR or at least 9:1 with some forged aftermarket pistons. thanks
    Well, the problem you are facing is that in order to up the compression you have to have dome on the piston. Since there is going to have a dome and be made for the z32, It is not going to match the combustion chamber of the z31.
    85 Z31 6.0 LSX turbo 766whp/792wtq
    04 GTO, LS6, big cam, porting, N20… underway for summertime daily driver.
  • 300zxtproject
    300zxtproject
    Member
    • 39

    #11
    yea i understand, thanks for the response. so it seems like the BRC 8.5:1 CR piston are the closest i'll get to the stock NA CR. thanks
  • Andrevas
    Andrevas
    Senior Member
    • 1481

    #12
    stop thinking off the shelf and look into what companies want for custom compression ratios that will work with SOHC heads. there's a reason so much shit is custom fabbed in this community, because there's little to no aftermarket =(
  • VG36ET
    VG36ET
    Senior Member
    • 190

    #13
    Andrevas wrote: stop thinking off the shelf and look into what companies want for custom compression ratios that will work with SOHC heads. there's a reason so much shit is custom fabbed in this community, because there's little to no aftermarket =(
    What he said.............. Guy think they can slap any pistson in their block…lol. Different valve cuts/reliefs and different pistons designs(dome, dish etc.) might not play nice.

    I don't like the bottom end of a 8.5:1 turbo car on the street to say the least. I'll take a 9:1 turbo street car any day over the later.

    BRC makes top shelf shit.........period. I wouldn't hesitate to use them again for ANY custom piston application from a N/A VG to the custom BMW V8 a friend is building. You don't need Ceramic coated tops but moly coated skirts is worth every red cent IMVHO and IME.

    Peace
    Ucked Fup!!!
  • DMANN
    DMANN
    Senior Member
    • 544

    #14
    BRC made 9:1's for my Z even made them to fit my stock rods--88na-t
    88na2T-s13,q45 swap 12.6@110mph
    87T 2+2 auto,stock