Hey Sam,

I have a Mark 30 2 - Port block - 1164 are the first few numbers of the serial plate.. It reads Turbo Four on the side. It falls below Grubbs serial number listing for 1958.. It actually falls into the Mark 28 Serial Group.. Would this be one of the mysterious 30H reconverted back to Mark 30 engines. It is a factory sealed motor. fairbanks mag and AJ51A carbs - two pumps..

I also found an ad for 1956 that shows a 55H in the twin blues color, Do you know if they were available in that colour in 57 as well..

What year was the carter to KA switch bulletin (kit) offered.

Regards,