Gear ratio

I've brought myself an Avenger RT for a daily driver so the focus on my 68 Valiant has shifted a bit. So summer daily driver has taken a back seat to best quarter mile time :)

It has 380hp create engine and manual shift body 727 with 2800 stall. Stock body and interior so stock weight.

From what I understand a 12 second combo.

Right now its got 2.94 gears with 245 60r15 and Im thinking 4.30 with 275 60r15 drag radials will give the best time??

Magazine dyno of a 380hp create engine
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