Yet another oil cooler question (sorry, advice needed)

Skipperdoodle

So I took my new to me Z to a track day a couple of weekends ago. The car is completely stock and I am well aware of the VQ oil temp issues. After about 10 minutes of lapping I was seeing 250~260*+ oil temps. I wasn’t even really pushing the car that hard as I was in the novice group and sessions were paced.

I want to get the Z1 oil cooler kit with the thermostatic sandwich plate, but I need pointed in the right direction of size. I’ve read lots of threads here with people saying that the 25 row is too much on the street and end up taping it down to 19 or so. But is 19 enough for the track?

My plan is to go 3 or 4 times a season once I sort this out and get better rotors and pads. So my car will mostly be street driven. Also, does anyone know at what temp Z1’s thermostat opens up?

Thanks in advance!