Bosch (4477) WGR7DQP Platinum +4 Spark Plug, Pack of 1

I have found these plugs to work well in my Porsche 928 s4 with Petrol as the Fuel, but it seems to be a different story with my other car which is an Alfa Romeo GTV Alfetta 1982 model which I have run on LPG / Petrol for a number of years. I originally used Gold Lodge four electrode spark plugs which the car ran well on them, but when I ran the Bosch Platinum x 4 she simply didn't like them. Off of idle it developed a slight miss and it ran rough idling. I suspect the centre electrode is simply to tiny as that seems the only thing that makes sense after having the gas mixture checked and that was spot on. I Think it shows that the LPG has a need of a big Fat wide spark to ignite the Gas mix. This is only an anecdotal report and would need to be repeated on a number of LPG vehicles. I went and checked with a friend who has fitted LPG for years and he confirmed that with LPG he found that over time they found that conventional NGK plugs worked best. -- Cheers, John