Testing the 273 on the dyno....

I think if you compare the HP & torque curves for a 273-4 and a 318-2, you will see a radical difference. Based on factory info, the 273-4 has an extremely flat torque curve with a peak at 4000rpm. The HP peak is at 5200rpm. This leads to an entirely different driving experience. Really, it's hard to take advantage of it unless you have a 4 speed.