Oil system in Italian car is sensible thing and below you can read my opinion, not my recommendation. I just share my experience.......
Almost for 2 years i don't use OE recommended oil filters for my cars, because i prefer better oil filtration. A lot of cheap fakes on the market as well.
I stick with MANN-FILTER W 719/22 - it has 2 anti-drain back valve, and it's bypass valve opening pressure is 2,2bar......most of aftermarket filters opens at 0.8 - 1 bar. It has bigger filter media which allows better flow.
I used it on my trackday 156 V6 engine for 2 years with Yacco Galaxie 15-50 or 10-60, and oil pressure was immediately when i start the engine. Another interesting fact is that if i stall the engine in 1 gear(to keep ignition ON for gauge monitoring) oil pressure drops not that fast than with normal filter.
We did 3 hours endurance race with Fiat Coupe 20VT recently and even with 120 degrees oil temps most of the time, pressure did not drop below 2 bar.
It has same thread as OE - M 20 X 1.5, but it's a little bit higher than normal.
https://www.mann-hummel.com/online-catal...lter/W%20719~22

Did someone have any observation using bigger oil filters?

Nice info. Thanks.

thanks for the info always good to test and improve on what we have. im going to go for a filter set up where i can change the filter element that way i can have a look at the condition of the filter each change.

What is the OEM by-pass pressure?

I do not think a higher than OEM by-pass pressure is necessarily a good thing. You are effectively adding a restriction to the oil system pushing the pump closer to a by-pass event, which is much worse than a filter by-pass event.

However increasing the flow capacity of the filter is a good idea and may lessen any risks associated with a higher by-pass pressure.

I always use Mahle OC 243. Ca 120 mm long. Can't say anything about the filter. It does the job so to say. No problems with oil pressure.

Most standard filter's by-pass opens at 0.8 - 1.2 bar.....and when it open on cold started engine when pressure is higher a lot of unfiltered oil is bypassed.....

I thought an oil filter's bypass valve was based on relative rather than absolute pressure, ie. it opens when the input pressure is more than 0.8 - 1.2 bar above the output pressure, not when the absolute pressue is over 0.8 - 1.2 bar?

In other words, it only bypasses the filter when the filter is overly restrictive or completely blocked, regardless of the actual oil pressue in the car.

Correct Graham, the bypass is for differential pressure across the filter.

Quote from one of the best oil related sites available.
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=309756

That's a good read ferrarist and a shed load of info that il take in later.