the l.p. pistons are 9:1 +/- so if you need pistons, those would be best for pump gas. you can zero deck the block (around 30/1000) and if you still want more, deck the head. on mine, I only took 12/1000 of the head for fear of raising it too high. it runs fine on 89 octane so will buzz a little more off eventually.
https://www.summitracing.com/parts/uem-1437-040/overview/make/chevrolet
