Bing's SR turbo elbow for KA-T...o2?

[Jedi_Car_Fan]

Callout: FuzzyFish(wrx)

I hear redtop SR’s have a small bung, while blacktops are the same as KA, which is bigger.

That is correct… redtop = small and blacktop = big.

Bings Ext has the hole/thread for the big O2