From the Reference Section:
- Street Cam Selection Guide
- Buick 455 O.E. Camshafts
- High 10's Secrets for Your Buick 455
- 400/430/455 Poston Cams Grinds and Numbers
- 400/430/455 Kenne-Bell Cams Grinds and Numbers
- Buick 455 Drag Strip Tests from Kenne-Bell
    - Buick 400, 430, 455 Engine Specifications
- Buick Staging Chart
- Differences Between 1970-71 And 1972 and Later Type Block
- Head Flow Chart
- Cam Button
Results 1 to 4 of 4

Thread: Decrease combustion chamber of 1975 455 cylinder head

  1. #1
    Join Date
    Jan 2018
    Location
    Tehran, Ir
    Posts
    24
    Rep Power
    0

    Decrease combustion chamber of 1975 455 cylinder head

    Hi everyone,

    Please inform me is it possible to make some machine shops on 1975 455 cylinder heads, taking some layers off, for decreasing combustion chamber from 78cc to 69cc like 1970 455 cylinder heads? If I doing such machine shops will it cause troubles? over heating or making cylinder head weak?

  2. #2
    you would have to cut a BUNCH off of the head in order to bring the 7.9:1 CR up to the 10.5:1 of the 1970 heads. and that would also require cutting the intake.

    as you reduced the height of the head, you lower the attachment point of the intake and necessitate narrowing the width of it and sometimes also slotting the bolt holes.

    and remember, there's a big dish in the 75-76 pistons. it doesn't matter how much you cut the head, you're never going to get that dish area back without a new set of pistons.

    it would be better to just shell out for a set of aluminum Stg 1s from TA. they flow more out of the box than a max effort porting job and alum can tolerate higher CR.
    The way to crush the bourgeoisie is to grind them between the millstones of taxation and inflation.
    Vladimir Lenin

    Government schooling is about "the perfect organization of the hive."
    H.H. Goddard, Human Efficiency (1920)

  3. #3
    You would probably have to take off about .040" for about 10ccs.
    At .040", you will almost certainly have to mill your intake manifold as mentioned.

    Other items to watch would be valve train geometry.


    WEBNOTE: When inserting an email in a posting, use the "smilie" @ so that web robots don't pick up your address and send you more junk mail!
    Members can be contacted by clicking on their "handle", but you are much better off to post to the thread!

  4. #4
    Join Date
    Aug 2015
    Location
    Oakland Ga
    Posts
    133
    Rep Power
    0
    You are wasting your money doing anything to 75-76 cylinder heads, they are open chamber. You are better off getting a pair of earlier heads, or as suggested, buy the aluminum heads. The aluminum heads out of the box with a good valve job will outflow the best ported iron heads.
    Larry

    1970 GS455 Stage1 Race weight 4025 lbs.
    TSP 470, 602 HP, 589 TQ
    MT headers, Gear Vendors Overdrive
    Best E.T. 11.54 Best MPH, 116.06
    1998 Riviera SC3800

Similar Threads

  1. 1951 Super Sedan master cylinder conversion to dual chamber
    By bioposi in forum Steering and Brakes
    Replies: 16
    Last Post: 07-28-2016, 01:19 PM
  2. 320 Combustion Chamber volume
    By Jyrki in forum Straight Eights!
    Replies: 7
    Last Post: 09-13-2011, 01:23 AM
  3. 320 combustion chamber
    By saltracer in forum Straight Eights!
    Replies: 5
    Last Post: 11-07-2010, 04:53 AM
  4. rebuilding a single chamber master cylinder?
    By andy74 in forum Tools, Shops, and Garages
    Replies: 7
    Last Post: 11-22-2009, 01:27 AM
  5. 430 combustion chamber
    By rcull in forum Big Block: 400, 430, 455
    Replies: 4
    Last Post: 11-24-2005, 07:06 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
TeamBuick.com Privacy Policy