line boring ???.....
+ Reply to Thread
Page 1 of 6 1 2 3 4 ... LastLast
Results 1 to 14 of 73

Thread:
line boring ???.....

  1. #1
    Senior Member
    Join Date
    Jul 2008
    Location
    Kingman/Golden Vly, Az
    Posts
    1,278

    Default line boring ???.....

    Pls explain... what has to be done in order to line bore a block?...do u have to torque the caps down?...does it chng the bearing size on the mains of the crank?...is it absolutely necessary when changeing caps?...all info appreciated

    thnx

    FastRat

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    Quote Originally Posted by FastRat View Post
    Pls explain... what has to be done in order to line bore a block?...do u have to torque the caps down?...does it chng the bearing size on the mains of the crank?...is it absolutely necessary when changeing caps?...all info appreciated

    thnx

    FastRat
    First, yes it is absolutly necessary when any cap not originally on THAT block is changed. Period, no question!!! Yes the caps are torqued to spec with the EXACT same type of fastners you plan to use. Studs, ARP bolts, stock bolts, etc. First the face of the cap is ground a couple thousands (or more if needed) to get it FLAT and SQUARE to the bearing bore. Now the hole is no longer round due to this. Then he machines it round by honing it, or boringif it was way off or the bearing bores where damaged. If he does it right, he will make constent checks to see how the hone is cutting, and may loosen a cap alittle to adust the way the hone is cutting a peticular saddle. When done, your bore are perfectly inline and dead perpindicular to the cylinder bores and parrallel to the deck. And the diameter will hopefully be on the tight side of the stock specs and thery DO NOT require special bearings This is the over simplified explanation, but it no simple task, and for the bad news, 1 in maybe 5 machinists that perform align hone a block know what the flock they are doing.



    100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3
    Last edited by gn7; 01-13-2010 at 05:12 PM.

  4. #3
    Senior Member ol guy's Avatar
    Join Date
    Mar 2008
    Location
    Lake Elsinore Ca
    Posts
    3,840

    Default

    Quote Originally Posted by gn7 View Post
    First, yes it is absolutly necessary when any cap not originally on THAT block is changed. Period, no question!!! Yes the caps are torqued to spec with the EXACT same type of fastners you plan to use. Studs, ARP bolts, stock bolts, etc. First the face of the cap is ground a couple thousands (or more if needed) to get it FLAT and SQUARE to the bearing bore. Now the hole is no longer round due to this. Then he machines it round by honing it, or boringif it was way off or the bearing bores where damaged. If he does it right, he will make constent checks to see how the hone is cutting, and may loosen a cap alittle to adust the way the hone is cutting a peticular saddle. When done, your bore are perfectly inline and dead perpindicular to the cylinder bores and parrallel to the deck. And the diameter will hopefully be on the tight side of the stock specs and thery DO NOT require special bearings
    X2! plus caps are matched from the factory and any change requires this.

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Gone
    Join Date
    Dec 2007
    Location
    Sparks, Nevada
    Posts
    1,824

    Default

    "and for the bad news, 1 in maybe 5 machinists that perform align hone a block know what the flock they are doing."

    Amen to that.

  7. #5
    Boat Nut sleekcrafter's Avatar
    Join Date
    Dec 2007
    Location
    South Elgin, Il.
    Posts
    5,131

    Default

    Why not bigger saddle dia. for the bearings, rather than cut the bore, and move everything north? I know how it's done, but the internals all get moved in the process.
    Upper Midwest Power Boat Association
    DRAG BOAT RACING UMPBA #926


  8. #6
    LP-25.com Infomaniac's Avatar
    Join Date
    Dec 2007
    Location
    New Port Richey, FL
    Posts
    16,861

    Default

    Quote Originally Posted by sleekcrafter View Post
    Why not bigger saddle dia. for the bearings, rather than cut the bore, and move everything north? I know how it's done, but the internals all get moved in the process.
    You loose the bearing crush if you just open up the bore. And line "BORE" would remove a lot of material then you have to hone it afterwards The bore tooling is supported on each end. You can manipulate the center of the cut.The hone just follows the existing bore.

    What you gain by moving the rotating assembly is worth it. It would be a lot of work to cut the caps and machine the registers to end up with the main bore in the same location when you are done.

    We don't cut the caps when we do the high end aluminum blocks. It r,moves the anodiizing from them. We sand the registers to close up the hole before honing.
    If For Some Reason I Do Something Worthy Of Recognition. God Provided The Ability And Deserves The Credit.


    QE 439 Twin Turbo

  9. #7
    steelcomp was here
    Join Date
    Dec 2007
    Location
    n/e TN
    Posts
    26,469

    Default

    BBig difference between align boring, and align honing...
    If God is your co-pilot, change seats!
    Acts 2:38, the perfect answer to the perfect question.

  10. #8
    Hat
    Hat is offline

    Join Date
    Jan 2010
    Posts
    204

    Default

    Quote Originally Posted by FastRat View Post
    Pls explain... what has to be done in order to line bore a block?...do u have to torque the caps down?...does it chng the bearing size on the mains of the crank?...is it absolutely necessary when changeing caps?...all info appreciated

    thnx

    FastRat


    Line boring consists of cutting the main caps on a grinder (special) to ensure the ground surface is paralell to the bore about .005 and reboring the hole to the original size, the only times that process is usually used now is to size new caps to an old block, like aftermarket caps, then when a size around .002" small is achieved the block is then line honed to achieve much better finish, and results, a good hone operator can hold .0002" from end to end on a 7 main 6 cylinder, and the same tolerance with a 5 Main V8.

    a good line bore tech should go for .000 at the block leave .002 to hone, thereby moving the crank up in the block a minimum amount

  11. #9
    steelcomp was here
    Join Date
    Dec 2007
    Location
    n/e TN
    Posts
    26,469

    Default

    I remember one team I worked for decided they were tired of taking the mains out of the blocks and instead, built replaceable inserts. They machined the block oversized and installed the inserts. (Alum block) I got the job of building the boring bar system so they could replace and machine new inserts in the block right at the track.
    If God is your co-pilot, change seats!
    Acts 2:38, the perfect answer to the perfect question.

  12. #10
    Senior Member
    Join Date
    Dec 2007
    Location
    Newbury Park, Ca/Mohave Valley, Az
    Posts
    8,169

    Default Block material

    If done correctly, the block will not lose any material. (assuming it was straight before you started). As mentioned, finding someone with the knowledge and equipment to line hone a block is tough. 4 out of 5 will make it worse. IMO, the shorter timing chain sets are proof some body screwed up and moved the main bore too close to the camshaft. This can't be a good thing if the bore was moved that far unless the crank C/L to cylinder perpendicularity was way off to begin with............Original stock caps on a block are usually damn close and IMO, better left alone unless there is an obvious problem. Replacement caps must be bored/honed to size and alignment, and held to .XXX to camshaft C/L parallelism and location....Ray
    LOUD BOATS SAVE LIVES

  13. #11
    Boat Nut sleekcrafter's Avatar
    Join Date
    Dec 2007
    Location
    South Elgin, Il.
    Posts
    5,131

    Default

    So you spin a main, just toss the motor? Just thinking...why not bigger o.d. bearing shells, same I.D. not cost effective?
    Upper Midwest Power Boat Association
    DRAG BOAT RACING UMPBA #926


  14. #12
    Senior Member
    Join Date
    Dec 2007
    Location
    Newbury Park, Ca/Mohave Valley, Az
    Posts
    8,169

    Default Spun main?

    Quote Originally Posted by sleekcrafter View Post
    So you spin a main, just toss the motor? Just thinking...why not bigger o.d. bearing shells, same I.D. not cost effective?
    I don't know. I've never spun A main bearing. I've wiped out all of them, but never just one. I didn't spin any, but the block saddles got so hot I was afraid of it......

    I imagine there is a "fix" to save the block, but all I've seen were scraped because like you said, "cost effective" vs starting over with another block.....

    Ray
    LOUD BOATS SAVE LIVES

  15. #13
    Senior Member lbhsbz's Avatar
    Join Date
    Oct 2008
    Location
    Long Beach
    Posts
    1,617

    Default

    Crap like this is why I always seem to go through 3 or 4 core blocks before I find one I'm happy with.

    I've had 2 blocks that one of the main caps twisted on and locked up the crank when studs were used...problem wasn't there with the stock bolts. Both of them are already bored and honed when I find this out.

    I'm getting kinda tired of it, but I'm not happy with the solution either...becuase line boring involves an interupted cut with very little material removal and no room for error, which means more likely than not, it'll get screwed up. Seems the price you pay to fix a block right any more...you could by a new dart block instead, but are they even straight?

  16. #14
    Senior Member
    Join Date
    Dec 2007
    Location
    Newbury Park, Ca/Mohave Valley, Az
    Posts
    8,169

    Default Straight?

    Quote Originally Posted by lbhsbz View Post
    Crap like this is why I always seem to go through 3 or 4 core blocks before I find one I'm happy with.

    I've had 2 blocks that one of the main caps twisted on and locked up the crank when studs were used...problem wasn't there with the stock bolts. Both of them are already bored and honed when I find this out.

    I'm getting kinda tired of it, but I'm not happy with the solution either...becuase line boring involves an interupted cut with very little material removal and no room for error, which means more likely than not, it'll get screwed up. Seems the price you pay to fix a block right any more...you could by a new dart block instead, but are they even straight?
    I worked in a shop that measured down to Millionths. Our stuff wasn't "perfect" even at that, but we called it "Adequate" for the task it was made for. Good word, Adequate........ What I mean is, how straight is straight enough?...........Ray
    LOUD BOATS SAVE LIVES

+ Reply to Thread
Page 1 of 6 1 2 3 4 ... LastLast

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in

Digg This Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95