To see a example go to isky’s site
smallenginecams.com and look at the cams for a gx200 under the custom cams you can select durations from 220 to 280 and lsa from 104 to 110. When the duration is 230 or less your v to p should not be an issue. As durations get longer the overlap period can grow. The lsa also will increase overlap when you tighten it up. Your post asked what the biggest cam you can run without v to p issues. That depends on what your trying to do. Are you racing on dirt or pavement? You mentioned SA engine so are you using a small block carb or a 390 carb? A small block carb modified by a top carb builder will flow high 60’s cfm a stock carb in the low 40,s if I remember correctly. That limits hp and in a case like that more duration can help. Also Barry young sells modified hemi pistons with valve notches very reasonably priced ( I think 40 bucks) should you need more clearance. Are you looking for a torque motor good off corners or a top end motor?