From my research, a conversion to vented 164 brakes is by far the simplest. The only question I have that I do not have a definitive answer for is if the lines are the same between the 140 and 160. I went so far as to order in one of each(I work at a dealer), a 140 line and a 160 line of the same position on the car (there are two part numbers per car, one of each on each side...140 #'s are 677712 & 677713, can't remember 160 #'s, but they are different). The lines were identical, despite the differing part numbers. The only thing I haven't confirmed now is the other set of lines. If my memory serves me correct the part numbers for 160 reman calipers are 5002019 & 5002020, and they are only 108.00 ea., with a 5.00 core charge..not bad really. I just replaced everything on the front of my 68 142, & went with stock stuff. Here in Oregon we have a mountain in the Coast Range call Mary's Peak, it's a nine mile road to the top, and driving all out on the way down is the only time my brakes ever showed any sign of fade. It was a purposeful assault to see where the limit was, and they went up in smoke with about a 1/2 mile to go. These brakes will hold up fine in autocrossing, with how short the courses are..probably the only time you might need more would be in road racing, and even then there would be more time off the brakes than on my mountain road. Just my two cents
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