cylinder liners

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  • SteveH
    Super Moderator
    • Jul 2003
    • 4460
    • Country: United Kingdom

    #16
    You can fit liners to the 5cyl lump. I know of someone who has an RS2 motor with 1 bore sleeved. If you do go this way and get it sleeved, it's best to go for a captive sleeve that sits on a lip at the bottom of the bore, rather than a top-hat type that sits on the block-to-head surface. I've heard of these cracking the lip and allowing the liner to drop into the sump end of the block...ouch!

    I'd have to agree with Lee, it would be a bad idea to go for sleeves on a high HP motor. Just get another block and have it bored out and honed with a torque plate, mains caps fitted, and the block heated to 90 degrees. In the end this could be far cheaper than rebuilding the whole lot again.
    91 Modded 3B
    14 A6 Avant Black Edition

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    • timucin
      S2Forum Maniac
      • Nov 2003
      • 869
      • Country: Turkey

      #17
      yep ok i have no problem with Lee's ideas;
      will install main caps,plate heat up ok.

      my current problem is: i dont have chance to find a used block here, and new is very expensive here..

      all i am wondering is doing without these stuff = is it impossible to turn back?
      may be i can take some tolerance from piston to wall clearence (its not at maximum for the moment)
      i will do everything told here today when i get there tomorow morning
      are you all sure block is gone?
      Quattro

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      • SteveH
        Super Moderator
        • Jul 2003
        • 4460
        • Country: United Kingdom

        #18
        Tim, Your block may be fine I'd get it clamped to a torque plate and have the bores accurately measured. You may find it's in tolerance.

        Anyway, if it's no good I'll buy those cheap pistons off you and you can go for 300hp with the standard oversized Mahle jobbies
        91 Modded 3B
        14 A6 Avant Black Edition

        Comment

        • timucin
          S2Forum Maniac
          • Nov 2003
          • 869
          • Country: Turkey

          #19
          thnx Steve
          Quattro

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          • Doug_RS2
            S2Forum Possessed
            • Jul 2003
            • 3847
            • Home: Scotland Current: England

            #20
            Timucin - what diameter are your pistons? What diameter has it been honed to?

            Becasue you are running nitrous and more power than us you are supposed to have an extra gap anyway.

            I think you need to get all the facts/sizes first before you do anything else with your block.
            S2,RS2,S4 WB,RS4,S4 B8,RS6 C5,RS6 C6,R8

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            • timucin
              S2Forum Maniac
              • Nov 2003
              • 869
              • Country: Turkey

              #21
              i believe i will fix everything tomorrow..
              81.5 mm
              Quattro

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              • Lee
                S2Forum Extremist
                • Jul 2003
                • 1512
                • Country: United Kingdom

                #22
                Larger gaps are required for high Silicon content aluminium pistons.
                1995 S2 Avant with some upgrades

                Designun Limited....
                Aerospace, Space and Motorsport Design Consultancy and hardware supply.

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                • Doug_RS2
                  S2Forum Possessed
                  • Jul 2003
                  • 3847
                  • Home: Scotland Current: England

                  #23
                  Our pistons are made from 2618 non-silicon aluminium alloy - whatever that means!

                  We didn't go with the Ross pistons as they had high silicon content and required large gaps - which is fine at operating temperatures but you get piston slap on start-up.
                  S2,RS2,S4 WB,RS4,S4 B8,RS6 C5,RS6 C6,R8

                  Comment

                  • Lee
                    S2Forum Extremist
                    • Jul 2003
                    • 1512
                    • Country: United Kingdom

                    #24
                    Ally 2618 has really god mechanical properties at elevated teperatures. That's the grade I want my brake bells made from but the raw billet price is pretty hgh...F1 bells are made from this material too.

                    Are they forged pistons or machined straight from billet?
                    1995 S2 Avant with some upgrades

                    Designun Limited....
                    Aerospace, Space and Motorsport Design Consultancy and hardware supply.

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                    • Doug_RS2
                      S2Forum Possessed
                      • Jul 2003
                      • 3847
                      • Home: Scotland Current: England

                      #25
                      They are forged.
                      S2,RS2,S4 WB,RS4,S4 B8,RS6 C5,RS6 C6,R8

                      Comment

                      • timucin
                        S2Forum Maniac
                        • Nov 2003
                        • 869
                        • Country: Turkey

                        #26
                        here are the ideas and experiences i collect from engine builders in states;

                        -most of the people say doing without or with a plate will affect less then .0005

                        anyway tomorrow is monday and i will be at machine shop in the afternoon,i will see what gonna happen
                        my steps will be:
                        -will mark the cylinders with marker pen
                        -will install plate
                        -will install main caps
                        and rehone; i am expecting to see some marks after this operation; if no then there is no problem; if yes (which is expected) i will try to use higher piston to wall clearence will go to .0037 max , if there are still marks then i will order a new block.

                        marking may not be very healty but easiest way to see, i will also recheck from several reference points with necessary equipment.

                        but i have a feeling that ; everything will be ok

                        will post the results tomorrow night..
                        Quattro

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