Spark plug help 1979 evinrude 150hp

[ranger168v]

Seeing a lot of contradictory plugs on the spark plug charts online, I got the set that evinrude recommended and they are surface gap but the plugs in the motor (previous owner) are not surface gap. What’s some input from yall,
Motor is the
1979 evinrude 60 degree 150hp serial ending 949c

[ChampioNman]

Plug chart says use either UL77V or L16V both are surface gap plugs for your 90* Cross flow motor.

[ranger168v]

Plug chart says use either UL77V or L16V both are surface gap plugs for your 90* Cross flow motor.

Aw could have swarn it was a 60 degree and the “industrial” were the 90 degree anybreason previous owner would run conventional plugs?

[ChampioNman]

Here is the plug chart we use. http://continuouswave.com/whal...8.pdf

[ranger168v]

Here is the plug chart we use. http://continuouswave.com/whal...8.pdf

I get the chart that’s how I found and bought the manufactures reccomended plugs, but is there a reason the previous owner ran tradition plugs not surface gap

[SEAHORSE]

Seeing a lot of contradictory plugs on the spark plug charts online,

Motor is the
1979 evinrude 60 degree 150hp serial ending 949c

The 60° 150 HP did not come out until 1991.

Serial number does not help, what is the model number of your engine?

[ranger168v]

The 60° 150 HP did not come out until 1991.

Serial number does not help, what is the model number of your engine?

sorry the last of the model is 949c my bad and yes I know as the previous poster stated it’s 90* my bad

[ranger168v]

Plug chart says use either UL77V or L16V both are surface gap plugs for your 90* Cross flow motor.

Turns out this motor does not like the plugs I got, fouled the surface gaps first trip out, I got the part number reccomended for the engine, if I go back to conventional plugs do you know how I find out which I get? I don’t remember what they were