400rwhp is safe on stock internals. Putting a turbo on this engine will easily get you there and leave you wanting more. My advise is to forge the bottom end first, that way you can turn up the boost. The B heads love boost and are very capable of the 600-700hp you're looking for. Forge it now or forge it after it blows, it's cheaper now.
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98 Cobra Coupe w/ shifter and Flowmaster, FRPP B springs, Tokico blues
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