273 blower cam

Ooommmppphhh!!! Yeah, I definitely wouldn’t turn up the tune on that with the cast pistons. I would go as far to use some VP octanium booster on the first tank, probably a half a can to 10 gallons for a little extra margin of safety. I appreciate the kink factor of the 273, but if I had to tear it down to notch the bores, then I would consider an industrial / truck type 318 with good bores to run some of these pistons.
They’re notched for both Poly and LA engines, and are made to run at generous clearances.
Sealed Power 2268P Forged Pistons Set For 1963-68 DODGE 318, 318LA STANDARD SIZE | eBay