Hex studs in head?

[Andy G]

Thanks Spriddler, I'll peruse over a whisky later.
Agreed Duncan, there's no sign of a head to the mystery fixings so more like grubs than anything else, and therefore dubious holding ability.
This one is likely to remain a mystery as the engine is now back in the frame and all buttoned up....unless, of course, I have done sommat wrong in which case I'll send more images, but fingers crossed I won't need to.
Thanks All for the comments, I guess I'll never know the facts, but it suggests an intriguing history.

[jackstringer]

I wondered if it was some sort of an attempt to prevent the head twisting but registering it to the barrel. You know the types, over thinking engineers looking for an extra 0.001 hp

[Andy G]

Not having stripped a 350 before, I guess I was mostly confused about what appears to be a two part cylinder head.
Bearing in mind the relative commoness of the model, low overall performance and availability of second hand parts now...why would a po even bother with a time consuming and expensive repair? Maybe there's a retired engineer out there somewhere who won a bet by milling out a damaged combustion chamber, fitting a billet of ali, and carving out the spaces for valves....if so, then you Sir, are a Legend and deserve the win whatever it was.
Or was the engine repaired far from a supply of spares but with access to a well equipped workshop...
Or perhaps it's an apprentice piece made from the scraps bin.
Who knows, but if anyone has seen anything similar I'd love to know why!

Perhaps this is one for the magazine, the bet-winning Legend may not read that there Interfret

[clive]

Perhaps a photo and letter to the editor.

[Andy G]

Done, let's see if anyone else can shed light..

[clive]

Done, let's see if anyone else can shed light..

You have missed the cutoff for the December mag (13th November) so it will probably not appear until January. Hope you are not in a hurry to put it back together although I see only one reason not to do so. One of your photos appeared to show some slight cracking or splintering below one of the valve seat inserts. Have you checked to ensure it is sound in that area?

[Andy G]

Yes, it won't appear this next issue but I'm more curious than concerned.
And thanks for pointing out that flakey area. I did notice and pick out a small fragment. Probably could have filled the gap but thought it safer to just leave it rather than risk anything else falling out. It's the intake side so I figured its just going to be a minor resistance in the airflow rather than something that could get worse with high heat.