Girdle installation

Discussion in 'Race 400/430/455' started by hugger, Aug 13, 2019.

  1. hugger

    hugger Well-Known Member

    So what is the procedure?
    Any measurements to adhere too?
    Can any competent shop perform this,..or is it only something a shop with hands on successful experience accomplish?
    Donuts & Peelouts likes this.
  2. Bens99gtp

    Bens99gtp Well-Known Member

    I dont know the exact steps, but from looking at the one I have/getting installed.

    The main caps need to be cut down and squared off. The arch on the bottom need removed.

    I would image the pan rails would need to squared off and parallel to each other and the correct height.......which means the caps need to cut ti the exact height as well.

    Then I'm sure the main bore will need to redone and finished to correct size after girdle was finished installed.

    On my current motor I had to replace the center 3 main caps with billets from program.......I think they can also make the outer 2 at a delay..........these well really add alot a strength if they could also be used in conjunction
    Last edited: Aug 13, 2019
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  3. dan zepnick

    dan zepnick Well-Known Member

    I have the installation instructions I can send you if you need it. Its precise on getting the correct crush.
    Donuts & Peelouts and B-rock like this.
  4. Steve Reynolds

    Steve Reynolds SRE Inc

    To do it right is a fair amount of work and having a very particular machinist do it is a big plus, if not a necessity!

    It's been a while, but I believe you start with the block sitting on the pan rails and clean up the china rails. Then flip it over onto the china rails and "kiss' the main cap surface (avoiding the register surface), and then raise up .250" and clean up the pan rail. Strict measurements need to be taken and then the caps machined to allow the proper "preload" on the girdle when toured down. (I can't recall the amount for certain, but I think it's around .001"/.002"?) The caps need to be squared up and machined in the proper process so they are truly perpendicular to the crank center line. Once all completed it needs to be main bored/honed to proper size.
    Each of these steps requires a lot of precision to be "right". I omitted a lot of specific details, but they're standard practice when doing precision machining. Find someone that has done this before, (successfully) with a good reputation, or at least a very particular machinist that's willing to do it right and talk to TA or someone that has done many. I've seen shops cut corners on this because they "know better"! That's NOT the guy you want doing your girdle install...………..
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  5. hugger

    hugger Well-Known Member

    That would be fantastic Dan thanks
  6. hugger

    hugger Well-Known Member

    I'm working a new fella,..he is young at 26 but graduated as the top student from SAM his year and even taught classes there they had so much faith in him. I get a really good feeling about him very humble, eager and hungry. I'm gonna let him do my 4?? For sure , he has one 455 now of ours just a freshen up deal. He has the equipment and we have the same local connections which are very respected. I'll put it this way the young man has $50k of billet blocks in his floor that he is doing the machine work on for a local no budget shop,...

    I've never had a girdle engine but never also tried what I'm fixing to try either so I'm contemplating doing a jockstrap
  7. Gallagher

    Gallagher Founders Club Member

  8. hugger

    hugger Well-Known Member

    Glad to see I'm not the only one that thinks to much is removed off the caps
  9. Bens99gtp

    Bens99gtp Well-Known Member

    X3, I asked about this when I took mine down, I think this is where the bullet caps would help too but man they are hard to cut down enough to get them into block. To cut them down enough for that would take awhile.

    But after loosing a motor to weak caps I thi knits something I will be leery of for awhile
  10. alaskagn

    alaskagn Well-Known Member

    3F8A1B74-85ED-47DB-A0A6-27A413C23BD3.png BC291D4F-DE22-418B-A441-90A5EB0D6679.png EA277295-FCF7-4D99-8169-ABABE22208D3.png 3A9A52D2-B231-43F2-8596-BC7CF744EC79.png 2374F274-5D33-4760-AF9C-471FB1034CD3.png 14847E54-EC0D-443D-AA9E-FABF61228A63.png 48EBFC2E-2E56-40C0-89C6-4901E9F50B3D.png 1AB29CAE-EC78-4CEC-952F-ABE16BA5FD77.png Figured I’d post the pictures I have of from the machine shop that has my block. Just for some reference.

    Yes a lot of material comes off of the main caps
  11. Bens99gtp

    Bens99gtp Well-Known Member

    Seeing that all that work is done off the cam tunnel, shows how even more important on these builds how that tunnel being true means even more
  12. B-rock

    B-rock Well-Known Member

    Id like a copy too please. Seems this would be something that is published. Would be nice to take the instructions to a machine shop while shopping for one.
    dan zepnick likes this.
  13. Bluzilla

    Bluzilla a.k.a. "THE DOCTOR"

    The first girdle I had installed about 25-years ago by a local speed shop. When I got the block back to my shop, I went to mock up the bottom end. Upon torquing the girdle down I found that the crankshaft would not turn. After taking the block back to the machine shop I was told that he had to line hone it a second time and it was good to go. I picked it up again and schlepped it all back to my shop. The next day I went to mock assemble the bottom end again, .... and again the crankshaft was locked tight. So after removing just the girdle and torquing just the main caps, the crankshaft turned fine. So I dropped my bore gauge into the mains without the crankshaft, without the bearings, and without the girdle. The bores were round. Then I installed the girdle/main caps without the crankshaft and without the bearings and found the bores to be ovals. The parting line larger than 90* from it. One grunt at the speed shop tried selling me on the notion that the parting line area is meant to be larger to account for the downward loading of the crankshaft to prevent pinching the main journals of the crankshaft. I felt the need to educate him that the wider parting line is engineered into the bearing, ... “Not” the main bores. So after thinking about what these guys are missing, I came up with the answer. I took off the main caps and placed a straight edge across the newly machined surface that mates with the girdle. The straight edge rocked back and forth. So the caps were crowned in the center, explaining why when the girdle was tightened down the caps pinched the crankshaft. When I called Mike at TA Performance and explained this, he asked me to find out how the speed shop machined caps and that they more than likely did not follow the instructions and after rough milling the caps, they should finish the caps in a “Surface Grinder”. So another trip to the speed shop just to find out they used a rod cap grinder to finish the main caps. After informing the speed shop’s owner that the problem is because of this, he informed me that I didn’t know what I was talking about. So I dialed up TA Performance and put Mike on the phone with the speed shop’s owner. After Mike explained to him that the cap grinder had too much deflection as it reached the center of the cap and that was causing the crowned main caps, .... he became furious and hung up on Mike. The speed shop’s owner then proceeded to tell me that the reason for the deflection in the main caps was due to the fact that the Buick engine blocks are pieces of “Schmidt”. Needless to say, I gathered my “Schmidt” and split.
    I ended up setting up a fresh block myself with my next door neighbor who was a machinist by trade, who had a surface grinder, and then went to a different speed shop for the final “Line Bore”. That girdle block lasted for 18-years in my Skylark and sold off to a board member to be used in an Econo-Rail.
    The botched up block was sent to TA Performance and Mike had to custom fit a new girdle to it. That turned out excellent.
    Bottom line is: Follow the installation instructions and make sure the caps are “Dead Square”.

    Good Luck,
    Last edited: Aug 27, 2019
  14. PGSS

    PGSS Well-Known Member

    What do the bolts look like or what kind are they that are used to secure the girdle to the block? I see the studs for the pan, but can figure out the main clamping..
    Last edited: Aug 30, 2019
  15. gus455

    gus455 Well-Known Member

    Peter, The studs that hold the pan on serve double duty, there is a small flange nut that goes down into a counter bore on the girdle. Those get torqued down and then the pan goes on and another flanged nut holds the pan on with the same stud. if you look close at the pictures Ben shared you can see it.
    PGSS likes this.

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