Is there any advantage to polishing the chamber or is it best left alone.

It depends on several things, which type of head, iron or aluminum,probally the type of fuel, alcholol ,E85 or gasoline, is it a closed chamber or open chamber head and do you mind increasing the CC of the chambers? I've seen stock cast Iron 426 Street Hemi head vary 4 CC between chambers Same thing on a set of stock 906 iron heads

Cab its Edelbrock RPM 84 cc
thanks

I was always told it helps reduce detonation. I did my Hemi heads that are aluminum. Polished up real nice...Don't know how true it is, but its cheaper than the Swain Tech coatings I was looking into.