4.390 and a block fill?

Basically, I scored a 4 bolt converted block, and I'm looking to swap my parts into it (4.300) or add stroke (4.500). My first though was to add a half or less fill in the water jackets. Use is street/sand/strip. And when I say sand, I don't mean 2 tracking or putting around. Think of it as heavy vehicle sand drags & hill climbs. 300' ish and low gearing. Sometimes hot weather, sometimes not (Michigan). Gonna make decent power on E85, with a dose of nitrous (150-250). Current setup has gone since '09 in a 2 stud Dove block, with slight cap walk, 700 ish power 6500 rpm. Thinking the caps would be economical for the added strength. But is any fill nessecary?

BTW D1 block.

My first built motor was hard blocked and was at a 4.440, but we could not keep her cool out there. Couple runs down the strip then sit. One lap around the dunes then sit. Hated it. It was all the way to the freeze plugs and a dove A block.
And I had everything possible on her to stay cool, but did not work.

Ray

At + .030" I don't see the need for a fill. The filled blocks do have higher oil temps.

That's what I kept reading when looking around, coolant not a big issue but hard to control oil temp. I'll just use a radiator for an oil cooler!   Or leave it. Thanks.

I personally dont see the need for HB on anything less than .080 unless the sonic check calls for it. jmo