Lee,
When I first bought my 86 Syncro GL a few years ago, it had Bosch Super 
single electrode plugs in it. I changed them with the Bosch Tri electodes and 
noticed a marked improvement in performace. I later tried the Bosch 4 prongs 
but noticed no perceptible difference from the tri plugs, so for the extra 
couple bucks more for the 4�s, I�m sticking to the tri�s.

Ra�l Cisneros
Nyack, NY
87 Syncro Westy 
86 Syncro GL (FS soon)
87 Syncro G (parts)