K24 bottom end with high compression pistons in the 12:1 to 13:1 range, K20A2 head with a mean port/polish and really aggressive cams, tune tune tune.
OR
J32A2 resleeved/bored with the same combination of high compression pistons, headwork/custom cams (not too many on the market), rev to 9k+, tuned to hell, probably 350-400whp easy.