Two seater, targa topped bus restoration (914)

Discussion in 'Restorations' started by mcswiggs, Feb 18, 2018.

  1. mcswiggs likes this.
  2. I’ve never used SS valves so have no experience with them . I probably would have bought new sodium ones and reused the barrels and pistons ....I’ve heard mixed reports about the new Mahle stuff . On mine I just deglazed , measured and used new rings , reground crank and NOS bearings . New valves , new guides
    mcswiggs likes this.
  3. (Uh-oh - I can feel I'm about to lose some ace-mechanic credibility points...)

    Yes! That's the ones! Great value aren't they and they are bound to fit!

    I think this is where I may end up too. Once I've sorted the P&B debacle. At the beginning of the thread I think you said you've got a WO - is that in your bus or have you got a 914 too?
  4. I agree I think you should try and reuse whatever you can. New parts nowadays aren’t made like they use to be.

    You can always cancel your order

  5. I think the AA high comp B&Ps were the ones to go for ...
    I’m currently on the lookout for a 914 ... nearly bought yours ....
    My 1700 WO is the same as the 914 1700 , high comp. and FI ... I rebuilt it with new FI and supercharger ...I just need something to put it in
  6. I’d cancel that order. ;) They might be good value and they will fit but they’re bus pistons and you’ll have difficulty getting the static CR high enough to work with the cam and heads.

    Clean up what you have, inspect and measure then decide if you need new B&Ps. Judging by what is visible in the pics they don’t look too bad but if the cylinders are tapered or ‘barrel’ shaped get them bored to 96mm and fit new pistons. As I said up there^ try to use the existing barrels (and pistons) they’ll be better quality than anything you can buy new.
    mcswiggs and Razzyh like this.
  7. Right, got it.

    CR of this 914 is 7.6, which is already low enough, and a CJ bus engine is 7.3. Have emailed those nice folk at VWH.

    Back to Plan A and for some measuring.

    Thanks for spotting!

    At least Lincoln City won!
  8. And the bus 7.3:1CR is with bus heads. The 914 heads have a larger combustion chamber volume reducing the CR still further if you fit bus pistons.

    Thinking ahead a little - A set of hypereutectic KB 96mm flat top pistons with your cylinders bored out will give 2056cc and a CR of around 8.5:1 (adjust the deck height with cylinder base shims) will work well with the cam, heads and FI. Hastings piston rings are good and available for KB pistons. Don’t bother with forged pistons; they’re totally unnecessary for anything but a race engine revved to above 7k, they have to have a large skirt clearance because they expand more than cast and rattle when cold.
    mcswiggs likes this.
  9. mcswiggs likes this.
  10. so Inspired by your thread and very nearly buying yours , today I have well and truly upset the wife and bought a 75/76 white Porsche 914 ....completely rust free , gearbox in the front , engine (1.8) in a different postcode ... boot full of parts and only missing exhaust and HX ....
    So I finally have something to put my supercharged motor in ......
    77 Westy, Flakey, paradox and 4 others like this.
  11. Now you need to start your own thread. Looking forward to this.
    mcswiggs likes this.
  12. We need our own nine fourteen section !
    mcswiggs likes this.
  13. Along with the Subaru & T5 section...
  14. Hello folks - work has been in getting in the way of play and I'm still trying to get my head around what to do re the P&Bs whilst I absorb your ideas from last weekend. Managed to cancel that order of new CJ type P&Bs from VWH without any fuss so that was good.


    The photos above are of the one (No 3) cylinder that is scuffed (it wasn't even the one that was jammed) - you can just make out how the oil ring groove has been peened by the scuff action, so it's toast. Unless someone has a spare then I deffo need new pistons.

    @77 Westy - thanks for the advice on rings and pistons - will look into sourcing these. This is the worst barrel that is a little rusty- so thinking boring out to 76mm is the way to go.


    Yep - I came across those guys a few weeks agao - look really good and think will be sending some euros there way very shortly!

    Now that is impressive and something of a relief that my wife isn't the only upset one out there. Will have to get them to swap numbers and form a self help group. Hope you're going to do a thread too, and can't wait to see the pictures.

    Right - time to put the pistons aside and crack that case open - so to speak....

    Attached Files:

    Last edited: Apr 15, 2018
    77 Westy likes this.
  15. Now then, the case is apart and has revealed its inner gloop:
    The sump has a layer of what looks like Farrow and Ball ‘lamp room grey’ emulsion over it.

    And the assessment of the innards has begun;

    The cam isn’t terrible but it’s well worn as was predicted. The gear looks ok so I’ll get the rivets drilled out and use it again.

    The worst of the bearings is the middle one where it looks like there has been movement of the shell against the case, although the dowel is in tact.
    63292BA7-B4B2-4E3A-BA09-E9516E3DF8D3.jpeg 8884D1D2-EFB4-44BC-95E1-E4B06A33078D.jpeg 6CE053DD-7B3F-41CA-9156-0ADCDB868EEF.jpeg
    Looking like a line bore needed?

    This weekend’s job will be strip and measure the crank.
    Merlin Cat and Aang like this.
  16. The matt grey finish on the casing face by the bearings and through bolts suggests there has been some movement but I’d only line bore it if I really had too; clean the case, bolt it back together and get it measured. The cam shows typical type 4 wear from the overlapping followers and I expect the followers are flat or concave – the cam bearings look good. The main bearing is not so good, is the crank scored?
    mcswiggs likes this.
  17. Yes the followers are either flat or very slightly concave - time for a new set.

    As you say the main bearing isn’t good, but from a brief look at the crank it’s not scored... BAEC5AD5-4973-42F0-9CD6-A0EBDBC3D639.png
  18. The bearing hasn’t rotated in the case and those marks are probably witness marks where they’ve been forced together for many years. Push the bearing back into the case, put a straight edge across the joint face and see if there is a gap between the bearing ends and the straight edge. And look at the ends of the bearing shells where they butt together – if they’re matt grey there’s been some movement.
    Merlin Cat and Aang like this.
  19. personally ....I`d reuse cam and followers ...I can`t see it needing machining .... I`d clean ,measure and put it back together with new bearings , new Bs &Ps and new valves and drive it
    mcswiggs and Razzyh like this.
  20. I wouldn’t reuse the followers; if they’re flat or slightly concave they’re at the end of their life. I agree the cam doesn’t look too bad but it has the typical wear pattern and I wouldn’t use new followers on a used cam. Whether you fit a new cam and followers depends on how long you want the engine to last but if you don’t there is not much point in replacing the B&Ps or valves, just clean them up, deglaze the bores and fit new rings and no doubt it’ll last a few thousand miles. Maybe 1,000 miles or 100,000.:D
    mcswiggs likes this.

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