rebuilding a slant 6

One of my cars has a stock slant/904 with a 500cfm edelbrock 4bbl and headers.
Goes well and returns good mpg.Abt 21mpg at our 62mph open road limit.Feels like high 17 - low 18sec 1/4.Haven't run it yet though but I've been racing for 35yrs so you get a feel.
Used to have a holley 600vac on it which was abt the same.

Here's an 1/8 to 1/4 conversion chart for you.



So that 9.89 is around a 15.45 quarter in a perfect world which is a pretty stout slant!!!

i awlays just thought it doubled haha... thx for the chart!