Spark Pluk REPLACEMENTWhich Ones

"Hi guys,

My 1987 Bayliner

"Hi guys,

My 1987 Bayliner Cierra Sunbridge 2550 complete with underpowered 305 and a 4bbl carb is being launched again after a 2 year hiatus. I did all of the usual pre-launch stuff but ...

Spark Plugs that came out were Champion RV8C and the ones I have looked up in a guide book say...RV15YC4. I am going by unknowns since I have the boat only 5 years...I always replaced the RV8 with RV8 but this Champion book with a 5.0L OMC in that year with a carb states this hotter plug

Being a hotter plug, is this correct? Or should I stick with the RV8's.

I did switch over to the Pertronix ignition and changed the shift assist module last week, any ideas?"

The RV15YC4 mainly improves id

The RV15YC4 mainly improves idling and reduce the risk of plug fouling. The change came in the late 80's.

"Thank you Morten,

I certa

"Thank you Morten,

I certainly appreciate the information...A friend of mine suggested the additional lettering and numbers on the new plugs may indicate exactly that and your confirmation is exactly what I was looking for, AGAIN, Thanks !!"