4 Vero29 COBS in a 3x3 tent, what is the optimal spacing?

I'm assembling a 4 COB setup for my 3x3 tent, what is the optimal spacing for 4 Vero29 38v 3500k 80 CRI COBs in a square tent?

Here's the max size I have with the 20" pre cut aluminum I currently have, is this good spacing or should they be closer/further? I also have some 28" pieces that I could use instead or trim if necessary

Thanks

The timbergrow 400w framework is 20"x20", so that would probably work

My 3x3 the COB's are spaced 14" on center and it's rocking the house.

looks good imo, but where did you source 3500k veros from?

I run my 1825s on 16" centers.

Seems fine for now.