Austin 1800 Rally car - BMC B Series

Hi Everyone,

You will need to be patient with me as I fully expect this build will still be going 12 months from now... but I have started, so would appreciate any assistance or guidance. I am not very mechanically minded but have daydreamed a lot so i guess that is a positive :) I have attached a pic of my end goal so everyone has some context and can see what I am trying to achieve... any comments are greatly appreciated.

I dropped the engine off at the machine shop yesterday.... my first question is..

1. Do they knife edged, lighten and balance the crank and THEN get it tuftrighted? Is that the correct order?

2. Which hardening treatment is best for older forged steel cranks please?

Thanks,

Stuart.

Yes, it's normall to do all the machining processes before the treatments as otherwise they'd be removed during the process. Well, almost all - IIRC, nitriding used heated salts and sometimes the crank would need straightening after.

Hardening was generally used to make the crank journals more resistant to wear, especially as the oils and filtration would be poorer back then and 'race' bearings had low embedability - this was rather important as the maching and materials back then cause a lot of 'running in' debris to get into the oil - and often air filters weren't used, so also increasing bore and ring wear.

Different steels - do you know what yours is made from? - may benefit from different hardening processes, if required, but unless I knew I needed one, I would probably pass.

The head was dropped off today for some pretty serious work, it was great to browse through all the previous head details on the flow bench software.. we are aiming for 100hp per liter so around 185 at the flywheel... the machinist spent some time explaining to me the issue of diminishing returns... we talked in depth about what I wanted to achieve and set a budget and timeframe... so all good :)

Just an update, getting more parts delivered... I have been very lucky to pick up some cheap ARP head and main caps studs on ebay... if you keep your eyes open you can still get the odd bargain.... Brand new head set for $40 (I just think the guy listed it incorrectly or didn't know what he had) and the main caps stud kit I got for $100 due to a guy buying the wrong ones by mistake and then re-selling it... just these two items saved me about $240... :)

If anyone needs a fantasic harmonic balencer then Glenn Paine from Pro-race.com in Melbourne Australia is your guy.. amazing product and much cheaper (at least for me) than others I have seen for sale..

Here is a comparision with old OEM and new super-duper damper.. just the looks must had 10HP for sure :)

As an aside, apparently collets and retainers for my head are rare as rockinghorse poo so I am super lucky that I kept my old ones.. my head is just about finished, doing final flow bench stuff this week... I will post the results when i get them.

:)

Things are moving a little slow for me at the moment due to Christmas and covid, but my Maxpeeding rods have arrived and I found out some interesting infomation..

I have weighed (just with the kitchen scales) my standard rod and the new Maxpeeding rod with the following results.

Original MOWOG 12H2445/6 = 854g

New Maxpeeding CR-MG-165 = 630g

So replacing the old with new reduces the rotating weight by more than one old rods worth of weight!!! 896G which I find amazing really...

Next on the list in flat top pistons, I have decided to bite the bullet and go with forged, they are very expensive but I think I would kick myself if I didn't do this..

Anyway, wishing everyone luck with progressing with your projects.. :)