Hey guys, is it worth it putting platinum sparks on this engine and if so, what is the optimal spacing for the plugs to get the most out of them? Any advice would be most appreciated.

 

You'll get more benefit out of a good coil and module. Those high-dollar plugs exist to crutch weak ignitions. Standard copper plugs will do just as well with a good ignition as any other type of plug.

If the ignition is otherwise up to snuff, .005-.010" increase in gap over the stock recommendation is usually a safe bet. Experimentation is required to determine the optimum gap your car wants. If you aren't willing to spend the time required to do that, set them to factory specs.

 

the best tuneing option for a 305...pitch it for a 350! j/k.... my recomendation is some basic bosch plats... like $2.15 a plug here.. if you want a gap thats a little biger i'd agree with five7kid no more then .010 over with stock plugs, wires etc.