Not tryin to sound like a dic but thats a pretty much impossible question to answer!
Seriously...not even close to enough info to make even a ballpark guess.Compression?Cam specs?timing?headers?exhaust?what size carb?head work?...I could go on.
Are you any good at dialing in a motor? You could give a guy a 800hp Cup motor right from Yates/Roush and he could have it putting out 250hp in 5min if he dont know what he is doing.
BUT...if I HAD to guess I would say at least 150hp.