BradH, What calculator did you use? The one I have always used here https://robrobinette.com/et.htm shows you needing 740FWHP to run a 10.5. I used to use the Moroso slide rule , but nobody I knew ever seemed to agree if it was actual RWHP or engine HP you were using to calculate E/T LOL Seeing your numbers gives me hope that 675+ FWHP in my E body that weights hopefully under 3550 race weight could run a high 9.
The Moroso one is Crank HP
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5