Not too sure where you're getting your own misinformation, but the SOHC B230 is normally considered a non-interference engine. There are a few rare cases where clearance may be reduced to the point of creating an interference situation, such as using an optional H-cam, K-cam (std w/B230K, not avail in North America), or shaving the head. However, the 4-cylinder red block DOHC 16-valve B234F and B204F engines that came in a few 740/940 models from 1989 (1988 in Europe) to 1991 are definitely interference.
Lulz this post itself is kind of hilarious and ironic;
B230K are the 631 ‘heron’ head engines w/fhe combustion chamber in the piston and a very complicated single carburetor (do they just love horrific carbs for the UK market?).
It is interference, but it has a T-cam.
We didn’t get those in North America; they seem to have been a largely brief niche UK phenomenon for the most part?
Economical (10:1 compression carbed?), but carbureted, but not quite 3rd world simple / 85octane gas compatible nor <2L displacement capped…strange niche SOHC redblock configuration?
I think even mostly found in 7 series of all things?
Presumably they’re all dead & gone by now / long since rusted out or MOT failed and scrapped?
Maybe you could still have a better quality car than a miserable rover in a volvo, but a fuel Econ spec of it back when computers and FI was still costly, but in a country that had better refined fuel was the gist of it, idk?
The K and H cam engines if the head is original height often the valves just barely touch the tops of the pistons, but not always depending how much above or below deck height the pistons are @ TDC (they vary some…very late cast crank B23s and B230s pistons just slightly above deck and earlier engines 4-8thou down oftentimes iirc?) and compressed HG thickness on B23Es I’ve found?
You guys got K-cam B23E ‘81-‘82, no?
B230 based boat engines we got in North America with K, H & V cams are often very slightly interference (it’s fairly rare that the valves actually hit / are fully open or cam stops in a place with valves fully open while the engine spins down, but i digress?).
All the 16V and whiteblock interference, but 90%+ of them expired ~10+ years before the other redblocks and will probably be largely forgotten soon enough, so no need to know?
or everybody knows?
Or everybody that needs to know knows?
Or something like that?
In the time of slop and misinformation / no reliable digitized source of green books and so many counterfeit parts and most OE parts long since NLA in the race to the bottom / specs getting lost in translation for the cheap repops, and so much wear and time the cars have been pounding pavement and mixed around, good luck making sense of any of it?
B230K with T-cam (not avail in North America', or a shaved B23E head. However, the 4-cylinder red block DOHC 16-valve B234F and B204F engines that came in a few 740/940 models from 1989 (1988 in Europe) to 1991 are definitely interference.
