News:

  • Home
  • Help
  • Chat
  • Login
  • Register

    • « previous next »
    Pages: [1]

    Author Topic: Stock Compression Ratio 71 Cuda 383?  (Read 930 times)

    Offline Total BS

    • Full Member
    • ***
    • Posts: 742
    • '71 Carrabuda Baby!
    Stock Compression Ratio 71 Cuda 383?
    « on: April 29, 2006 - 11:27:38 PM »
    Hi gang,

    I am trying to order a ignition system for my 71 Cuda and the company is asking me what the stock compression ratio is to best supply what I need.  Can anyone help me out.  I have a 71 383 4-BBL, auto w/ A/C.  Any help would be appreciated.
    Logged
    1971 'Cuda 383
    1970 Chevelle SS LS6
    1999 Durango
    -New Joisey-


    Offline Ghost

    • Resident
    • *****
    • Posts: 2912
    • I miss my Barracuda :(
    Re: Stock Compression Ratio 71 Cuda 383?
    « Reply #1 on: April 29, 2006 - 11:33:34 PM »
    8.5 to 1.
    Logged

    Offline Cuda Cody

    • Resident
    • *****
    • Posts: 3988
    • Vancouver, WA
    Re: Stock Compression Ratio 71 Cuda 383?
    « Reply #2 on: April 30, 2006 - 01:11:36 AM »
    In 1970 a 383 was 8.7:1 for a 2 bbl and 9.5:1 for a 4 bbl (per the factory manual).  Not sure why they would drop so much for the 71's?

    Is your engine still all stock?  If not, you're in the same club as I am.  You really have no way of being sure.  Changing the pistons, cam or heads can changes the compression ratio a ton!
    « Last Edit: April 30, 2006 - 01:28:23 AM by C O D Y »
    Logged
    The funniest thing about this particular signature is that by the time you realize it doesn't say anything it's to late to stop reading it.

    Offline Total BS

    • Full Member
    • ***
    • Posts: 742
    • '71 Carrabuda Baby!
    Re: Stock Compression Ratio 71 Cuda 383?
    « Reply #3 on: April 30, 2006 - 10:14:41 AM »
    Thanks guys...

    Cody, as far as I know the only thing that was changed was the carburator and intake at some point. I just had the engine rebuilt to stock with a little cam upgrade which I have the paper work on.  That is why I am trying to figure out the original compression ratio so that they can put together the right package for my setup. Being technically inedpt, its not easy...lol
    Logged
    1971 'Cuda 383
    1970 Chevelle SS LS6
    1999 Durango
    -New Joisey-

    Offline FY1 RT SE

    • Full Member
    • ***
    • Posts: 630
    Re: Stock Compression Ratio 71 Cuda 383?
    « Reply #4 on: April 30, 2006 - 11:34:18 AM »
    A '71 383 magnum produced 35 hp less than the '70 magnum.
    Logged

    Offline Ghost

    • Resident
    • *****
    • Posts: 2912
    • I miss my Barracuda :(
    Re: Stock Compression Ratio 71 Cuda 383?
    « Reply #5 on: April 30, 2006 - 02:37:26 PM »
    Quote from: C O D Y on April 30, 2006 - 01:11:36 AM
    In 1970 a 383 was 8.7:1 for a 2 bbl and 9.5:1 for a 4 bbl (per the factory manual).  Not sure why they would drop so much for the 71's?

    Emissions regs.  Every HiPo engine, except the HEMI I believe, lost some compression.
    Logged
    Pages: [1]
    « previous next »