I am changing out the spark plugs on a 1967 273 Sb. It's in my 73 dart and i am running a Weisco HEI ignition in it. I was reading through some books of mine and the champion N9Ys were listed as a good spark plug for the street.

But i presume the 9 is the heat rating, and that seems a little cool for a street engine with the lower compression my engine has ( i believe the 67 2barrel had around 8.8-1?)

Any thoughts?

thats what I thought.

Any recommendations?

My "Glenns" manual is showing Champion n14y for 2bbls and n10y on a 4bbl. EDIT the difference is based mainly on the higher CR on the 4bbl unit(iirc 10.5 adverised). I'm assuming you have a 2bbl eng & built it up a little? 12's or 14's might be a good start and I think there are excellent plug reading pics in the archives.