240 James's ill-advised B21AT R-Sport turbo build

jamesincJames @jamesinc Oz Volvo Ice Fortress
edited September 2020 in General

I am building a B21. Not enough people love B21s, so I am going to hold the candle for them.

Below is a jig I made years ago, originally for cutting the tops off glass bottles, but it's useful for so much stuff! You can put it under heavy machines to wheel them around, and you can hold pistons with it while you drive out the gudgeon pins.

I measured the bores and pistons with a micrometer and a dial bore gauge and everything was in-spec (about half way between min and max marks) and not too much ovality in the bores so I just gave them a quick hone and then packed everything up to go to the machine shop for thorough cleaning and deck surfacing.

More to come, some of you will, I hope, particularly enjoy this build.

paul0075Spacbgpzfm142alphaxcarnut222242GTpigdogiceton1975pauljlozdeNsand 3 others.


  • The B21 engine was, after all, the power behind the 1986 ATCC winner.

    What are your plans for it - NA, old school K-Jet turbo, Volvo Turbo Cup carb turbo, or..... Top Secret TBA?

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    @bgpzfm142 it's a secret for now only because I haven't quite finalised my plans, this thread will probably be drip-fed updates for the next month or so while I contend with a few things and do some skiing, but as soon as I know what it's going to be I'll post here (I'm terrible at keeping secrets anyway).

  • I spy corona - BEWARE! :)

  • Will be interesting to see your B21 build progress, I haven't seen one being done up myself.

    Hopefully parts are readily available for the B21?

  • All heads fit a B21, however unshrouding valves is not 100% possible due to the edges of the chamber matching the bore size. A 405 head from a B23 does fit though.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    For the most part, yes, though "A" pistons (with the dish) are hard to come by. GCP had 5 in a 0.50mm overbore with no plans to get more. I decided not to overbore as my clearances were still in-spec for standard bore.

    As others have pointed out, beyond that the B21 and B23 are very similar for parts.

  • Good to hear, should be minimal hiccups in your build then :)

    And nice to know some of the parts interchange, I still have plenty to learn on these cars.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    Block is cleaned up now, still waiting on a couple more parts before I can really reveal what my goals are here! Unfortunately due to FedEx being shit, all the parts I'm getting with @VolvoHordz are still out there somewhere in a dusty corner of some warehouse 😢

    And I forgot to order freeze plugs! So I have to track down some of those first.

  • How big is that bore worn? There's a bit there gauging on the top of the bores.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    Yeah there was some damage most of it came out with the hone. Bore is about halfway between min and max tolerances for standard size

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    Check out these Glyco bearing shells, pretty bad corrosion! Fresh out of their vac wrap. They've obviously sat for a very long time.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    Top weather led to more progress on the block today!

  • James we carry freeze plugs at Autobarn. Just measure the size you need and give your local shop a call.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    That's good to know, I already have some Volvo ones for this block now. I tried the Repco near me but they didn't have shit.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    Finishing what I started yesterday, today I cleaned up the sump, removing a couple of dents along the way.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress
    edited September 2020

    Small update of the past few days' work. Finished cleaning the pistons, checked all the clearances, checked ring end gap, everything nominal. Installed new head alignment dowels and assembled pistons onto rods. Holding off installing rings on pistons until I have the crank bearings, auxiliary shaft bearings, and remaining freeze plugs sorted and the crank installed. Then I'll do it all at once and install pistons as I go.

    I use Redline assembly lube on moving parts as I assemble them. It's good but if you're planning to let the engine sit for a very long time before running it, consider something with more tack like royal purple.

    Edit: after looking at the above photo I was concerned I'd put the #3 rod on backwards, but on closer inspection it is correct and for some reason this rod has the cast markings reversed.

  • jamesincJames @jamesinc Oz Volvo Ice Fortress

    I'm waiting on aux shaft bearings for at least a few more weeks so won't have much to report here I'm afraid. I've torn down some hoses, I'll take them to Pirtek at some point to be remade:

    I suspect many of you have started to work out what I'm building.

  • No idea! Looks like AC and/or PS hoses...baffling! :)

  • SpacSpac @Spac Canberra-ish.


    You’re building headaches.

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