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chev motors

Discussion in 'Chevy Trucks' started by chev4life, Jun 1, 2003.

  1. chev4life

    chev4life Junior Member
    Messages: 29

    i was wondering if anyone knew if i could change the heads of a chev 350 and put on chev 305 heads for more compression? if i can ill be happy :D if not ill be :realmad: ahhahahah thanx.
  2. Pelican

    Pelican 2000 Club Member
    Messages: 2,075

    I believe the heads will physically interchange, but whether or not it increases compression will depend on which heads are coming off vs. which you're putting on. Generally a decrease in the size of the combustion chamber in the head will increase compression, if you accomplish this in your exchange, compression should go up.

    I'd be concerned that you'd be sacrificing valve and port size in this exchange, I'm fairly certain there are small chamber 350 heads available that would increase your compression while allowing you to retain or even increase the size of the valves and ports.
  3. Patrick Gleason

    Patrick Gleason Junior Member
    from Chgo,il
    Messages: 12

    :rolleyes: Why not check with your local machine shop to check and see if the heads can't be shaved a bit this should give you more compression,just remember if you re do the top end of the engine you may have problems with the bottom end depending on how many miles are on the engine:confused: :confused:
  4. John DiMartino

    John DiMartino PlowSite.com Veteran
    Messages: 2,154

    Some 305 heads,the HO305 used in 83-87 305HO z28's and Monte SS had 58cc chambers.Im guessing these are the ones you want. The Vin number code is G for the 5.0HO.The standard 305 is code H and has 64CC chambers.The best way to get more power out of a chevy for the $$ is the new vortec heads.You can buy a brand new assembled pair for about 440 bucks,when they are on sale.You may need to change the intake also. Most of the 305 heads are tired,and need rebuilding,the seats are likely worn,as wil be the guides,and valves will need grinding.
  5. wyldman

    wyldman Member
    Messages: 3,265

    John is right on the Vortec heads.They are the cats meow on an older small block.Performance of an expensive aftermarket head without the big expense.$450 bucks is pretty cheap for a good set of new heads.For that price I wouldn't even bother with the 305 heads.