I'm not sure who or what your talking about with the RWHP,I NEVER use them only engine HP to weight.You make a point that I assume everyone would already know,if the combo isn't optimum(most aren't) the HP output could be better than the calc numbers. My buddys car runs 191plus in a 3500lbs car,the calc says 1903.4hp. It's very close as it makes 1616hp at the wheels and 1920something at the crank(he could put the same engine on 5 dynos and get very different numbers). The same calc matches most combos very well. It looks to me like the op is missing some et as 1.39 60ft is very soft for the weight and output. Sorry to the op for this getting off your post.Nice combo!