Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Can I get a 454 to a 502?

Discussion in 'The Garage' started by BlackDog714, Dec 15, 2002.

  1. BlackDog714

    BlackDog714 1/2 ton status

    Joined:
    Jun 8, 2002
    Posts:
    260
    Likes Received:
    0
    Location:
    Indiana
    Can I just bore the '75 454 block to accept 502 pistons? According to GM the stroke is the same, so it should be just boring the block, right? Are the new 502 blocks siamesed? Hell for that matter are the 454 blocks siamesed? Can this be done?
     
  2. Shawn

    Shawn 1/2 ton status Premium Member Author

    Joined:
    Feb 17, 2000
    Posts:
    1,753
    Likes Received:
    5
    Location:
    5280'
    No you can't for the reason you just said. The 502 has siamesed bores. The most you would want to bore a 454 is 100 over which is pushing it for a reliable non-track engine. I was going to push my old 454 block to 100 over but the machine shop didn't reccomend it for my application.

    Little info on BBC's here:
    https://www.spoperformanceparts.com/store/catalog/Category.jhtml?CATID=343
     
  3. HarryH3

    HarryH3 1 ton status Author

    Joined:
    May 31, 2000
    Posts:
    10,384
    Likes Received:
    2
    Location:
    Georgetown, TX
    Of course, if you want to spend some more money, you could get close by building your 454 the way Shawn did. /forums/images/graemlins/shocked.gif A stroker crank and a 30-thousandths (I think) overbore will net you a 496. Shawn's 496 alters the rotation of the earth when he stomps on the loud pedal! /forums/images/graemlins/thumb.gif
     
  4. BlackDog714

    BlackDog714 1/2 ton status

    Joined:
    Jun 8, 2002
    Posts:
    260
    Likes Received:
    0
    Location:
    Indiana
    Yeah, I was thinking about the 496, but that adds a huge difference in cost (i.e. new crank!) How big can I go with the block that I have?
     
  5. Z3PR

    Z3PR Banned

    Joined:
    Mar 30, 2002
    Posts:
    19,217
    Likes Received:
    0
    Location:
    Everywhere
    If you're putting in new pistons, raise the compression raito !!!!!! Get it up there as high as you can for the gas you'll be running. The hot rod 383 Stroker I had in my Camaro was at 10.2 to 1 on 91 octane gas with no problems (no knocks or pings).
     
  6. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

    Joined:
    Dec 14, 2001
    Posts:
    22,063
    Likes Received:
    70
    Location:
    Pleasanton, CA.
    You can safely go with a .060" overbore on a 454. If you want to go any larger then you should sonic test the block for thickness and concentricity. Before you even waste any time doing that though I would suggest finding out what the commonly available oversize pistons are. You may find that you can bore the engine oversize larger than you can find off the shelf pistons for. If you have to have pistons custom made then you are looking around 600.00 and up for custom pistons to be made.
     

Share This Page