What type of racing? A 327 is not a bad choice for a light bracket car. They can be made to live at high rpms with little investment. A good set of X rods and steel crank will hit the 7k rpm mark pretty easy. Cam and heads to support it and 450 500 hp comes pretty easy in full race trim. And can live long enough to finish the season.
Now if you have a spare dart tall deck block...
A lot of 327 have won a lot of races. Go to the track and ask one of the fast cars will have a 327.
It is more costly to get a 350 and even more for a 400 to turn the rpm that the 327 can handle. The short stroke has its advantages. A 7k rpm 327 is about 5 grand a 400 that can turn the same 7k will be 15k but make a lot more power. So in the end a 327 may be the correct choice for your car. But as all others have said the cube can make more power.