Mine is a 66 with the original 170 I-6 in it. It runs like a champ. As far as power, I can run 55+ up and over the mountains. The I-6 is a proven champ! As far as a carb...be careful using a carb off of a falcon I-6. They mount up perfect, except that the throttle arm in moves in the vertical direction instead of the horizontal direction on a bronco. You can but the falcon I-6 170 carb from the parts house for around $120, but like I said, you will have to modify the throttle are or you cable. I advise against it. I ran a falcon carb on mine for about a year and I recently found a old bronco carb and throttle cable to put back in place. It runs a lot more strong than before. If you want my 1 yr. old falcon carb, let me know. I will pass it along to you for a good price. I know Clifford carries a 2-barrel for the I-6 170, but it is expensive. Hope this helps.