I have just changed the oil and filter on my new to me 998 and it took 3.8 litres. How much more does a deep sump 998 take?
not much difference , its still less than 4 litres. as i understand it, the tapered deep sump design change was to ensure that there was oil available to the crank and pump even when leant over at speed
That's buggered it then, I should have bought an S because I am planning on leaning mine over at speed.