have done the 700 and 720 from d and d they run strong and reliable if set up right. Get the pistons and pipes coated add power breather, stock carbs, 3 degree timing key there clutch kit and go hunting.
Hunting for other sleds. I didn't say no jetting changes just stock bore carbs as you know each sled is different and jetting and fuel settings will be determined by your location temp etc. I always ran the stock 38 carbs with 370-390 mains depending where I was.
I'm doing a 720 on a f5 this year I love these motors. I had a efi in 98 hated it so i have no choice. AC's efi system is stone age tech compared to your car or anything else efi. I have heard the calibration is much better now but i won't do efi again until there is some adjustability if ac claims 140hp and it runs like 128hp you have no way to tune. f7 carb I'm in.
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