AM going to buy a compression tester for 92 Volvo 740 w/ B230FT engine. The spark plug type is Q16RU11. Need to know what size adapter I will need to use with this Volvo. At least that is the plug type called for in my Haynes which covers thru 91 model.... probably the 92 model used the same type. Did a search for this spark plug, but did not find a site with specs.