Re: Champion QL77JC4 vs. QL78YC
sandbass,The QL78YC plug has a taller electrode and fires a bit deeper in cylinder.Don't know if your 225 calls for it as an optional plug or whether you would experience better operation than with the QL77JC4.My 95 70 rude calls for the YC plug and lists the JC4 as an optional.