drove the Nissan Sentra (almost 7 years, 4 speed auto) on the previous oil filter change, and just driven the car again today
ok quick review on Torco SR-1 xw20 mixing with xw30 (engine spec on xw30):

- mileage over 11-12k km
- did an oil filter change around 8k km, absolutely no topping up of oil done because there was no reduction

without overdrive, low rpms (sub 4k rpm) car seems a bit meh, by all means the engine oil is bad, it's more like it lost its "torco feeling" (insanely fast revs) somewhere between the 8k km and 11 or 12k km, because when i done the oil filter change that feel was still there however today it just wasn't there.

that said, once the engine's momentum kicks off after 4k rpm that feel gradually returns until you start to red line the car, yes THAT's that feel that i was looking for

did a few launches with the sentra, the kick wasn't so strong as before, but since it's a 1st gear lock launch, red lining isn't hard and its very easy to get the momentum going from there.

from this usage experience, i think 7/8k km filter change and 14-16k km full drain is a bit too much for the engine oil especially when it comes to performance enthusiasts. (i am assuming people buying this oil are all petrol heads/red lining junkies )
i think 5-6k km oil filter change, 10k-12k km full drain would be more appropriate. or maybe something along the line of 8-11k km straight just full drain depending on your original manufacturer's specifications anyways. (the sentra's oil filter is really small btw :S)