Easaly 400hp. You might want to consider a small port inkake manifold with that setup. Something like the Edelbrock 2v ports with 4v carb.
You can get them cheap used on ebay.
You can use just about any carb you want with that set up and get 450hp. Even a 600 Holley.
Expect it to run out of oats by 6500 though.
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