Coolant Expansion Tank Size?

[Nordicskier]

For the typical EJ255 engine in the 818, what is a good coolant expansion tank size. I would like to replace the subaru plastic bottle with something that looks better. wondering if the system with more coolant would expand more than on the WRX, and what that translates to in terms of size? I haven't measured the stock plastic bottle but it appears for be around 64 oz? Has anyone tried a smaller bottle, say 20oz, and is it adequate?

[Bob_n_Cincy]

I used 1 quart tanks with no issues. Thee one on the right is for the cooling system. On the left is for the AWIC system.

https://thefactoryfiveforum.com/attachment.php?attachmentid=100652&d=1547369212

[DMC7492]

https://www.napaonline.com/en/p/NDP7304514
I used two of these one for engine one for AWIC
100653 100654

[Mitch Wright]

I am using one of these mounted in the engine bay https://www.summitracing.com/parts/ctr-80-201
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[Sgt.Gator]

Many racing organizations require a 1L or 1Qt minimum, if that matters.

[Hindsight]

I made a custom one that is about 1.5 liters or so. The OEM one off my 07 WRX donor was too small to stay full when both hot and cold, due to the added value of the coolant in the 818.

[Nordicskier]

Thanks for all of the ideas and validating some assumptions.