Yeah I've seen that. My engine was only recently rebuilt by the previous owner though. Doubt they fitted restrictors, but I'd rather not replace a new HG and timing belt if I don't need too. Seems the larger baffled sump is the most fool proof way of stopping oil starvation anyway.
As in article it's due to too large holes feeding the head and not big enough holes returning it to the sump in turn the top end is fine but the bottom end is starved Yes it's a ball ache but it's worth doing as Nissan did with the 26 just my 2 pence
If you do find someone that does the wide wing sumps let me no as I'm going to be making one for mine soon with baffles but would rather just buy one n hav a beer
