I think the target rwhp I used for the RX-7 is accepted by most as an accurate number. It's not the highest one I've heard discussed. The powertrain loss was a conservative assumption. Even if you use a less conservative assumption, the min weight for the E36 with the SIR comes out of the equation lower than where it is today. That leaves us with the adders and subtractors. The BMW has some benefits over the RX-7, but the RX-7 has some benefits over the BMW too. I'd like to understand how the subjective part of the weight spec was made.

Fred