I am going to change today spark's and coolant need help

[NoHachi]

Sparkplugs are sparkplugs..it isn't that difficult an item to produce and the differences are minimal..It would do you a lot more good to just make sure you have exactly the right kind (from manual) and have the gap set according to specs (also manual).

Regarding coolant...almost anything will work. The best cooling substance out there is...........ordinary water. Add a dash of washing up liquid for the best effect. Anti-freeze you add so the thing doesn't freeze up on you during winter. Otherwise water is fine. If you don't plan on changing it often, just throw in a correct mix of antifreeze for your climate conditions (any kind is ok, instructions should be on the side of the bottle).
Cleaning the radiator is difficult..Just give it a good couple of flushes with a hoze and you should be fine. Otherwise there are some radiator flushes available for mucho bucks, but I suspect they do nothing for you.

And by the way: check you plugwires too..they might cause the same problem.