The only way to know is to take the head off; not that big of a deal.
If it was built for racing, vintage racing or anything else, you should seriously consider it’s suitability for a road engine. 38mm chokes tells you something.
Many moons ago, I bought a Gordini F2 engine and opened it up to have a look.
It had everything you’d expect - Gordini pistons & rods etc.
It also had the head shaved, a cut down cam with the dizzy mounted on the end. The compression ratio must be . . ummm . . . pretty high.
It used a remote water pump driven by a belt and had the coolant inlet on the other end of the head and modified to reverse the coolant flow.
The carbs were DCOE45’s with 40mm chokes and it used triple valve springs.
The guy I bought it from said it had been blown up more times than I’d had hot dinners. When I asked him why, he said it was because he was trying to keep up with the Golfs. Golf engines have a good reputation for holding together in such situations.
As we know, careful attention needs to be paid to valve lifters with these engines if you’re using a big cam.
I found the cam had been reground (likely more than once, understandably) but the lobe base circles were very close to the rough cast diameter of the cam. In a couple of places, two tappets were clipping the edge of the raw cam casting!
The engine had been freshly rebuilt and looks like no one noticed that.
Needless to say, this would be unsuitable for a road engine, quite apart from the water pump and dizzy placement issues.
I really only bought it for a few interesting bits.
It has a genuine Renault Sport dry sump, Gordini rods which are useful, a Gordini rocker cover and a very neat / small / light Sachs clutch. The clutch uses a solid plate and is splined to suit a Hewland but the pressure plate tested up to spec. I figure I might space the pressure plate out and use a more conventional driven plate.
Sorry for the long rant, but that’s the problem with race engines.
They cost a small fortune to build but they’re not much chop for the road. The other thing is that racers don’t typically buy, or pay a lot of money for an unknown engine built by someone else.
With that said, your engine doesn’t look to be as extreme, but you’d likely still need to change some things.
The up side is that your 821 engine is in good shape and you don’t need to make a quick decision.
I’d be sorely tempted to de-tune it a bit because you’d end up with a great engine.
Cheers,
Gavin