I am only running a 50 shot and I am using the stock plugs and so far they are fine, I took a look at them recently and nothing looks bad yet, with a 75 shot or bigger I would run a one step or 2 if you could get away with it plug. Some blowers I have worked with we have ended up running 2 steps colder and its been fine, also that is with top shelf ignitions and plug wires etc.. I think you should be fine as long as you run only premium fuel. Just listen for any knocking or pinging when you spray the nitrous, if so, a colder plug can help...With bigger hits of nitrous, the plug type can really matter but not with 50 hp. Sometimes the platinum plugs can actually have problems with the flame kernel at high nitrous levels and you need copper large electrode plugs and sometimes you neeed to close the gaps on the plugs, personally I have never fooled with nitrous at thes e levels ( 400 h.p or so just from nitrous)..But with everything I've fooled with that has never been a problem. Hope that helps, let me know what hp shot you are using!