I have a 90 350 wont start gets spark fuel timings good control mod is good stater is good...help?

Sometimes even when you have everything you mentioned, the gas isn't being drawn in. I would try getting access to the carb air horn and squirt in some gas. If that gets it to fire, your choke is not working properly. You might also have some blockage in the carb itself.........get some spray carb cleaner. Personally, if it fired after squirting in some gas but was still hard to start, I would pull the carb and clean it. Use a paper clip to clean out the orifices.