4 lb Fireline - casting distance with varying spool sizes?

[Ultralight]

I've done some test and am a bit curious as to what the experience of this forum's members are.

I've always thought that larger spools tend to contribute to longer casts.

However, a nicely broken in 4 lb Fireline has very little memory. So I did a test of casting distance versus spool size with Fireline.

One reel was a size 500 Daiwa.
The other was a 5.71 cm (2 1/4 inches) spool size. Much bigger than even the size 3000.

I cast both with lines that have virtually zero memory (i.e. broken in fireline, spiderwire)

I found virtually no difference in casting distance.

Of course, it is possible that the large spool reel is too large with the sweet spot somewhere in between. I'm not sure.

Currently though, it seems to be that 4 lb Fireline that's broken in and limp does not necessary cast further with larger spools.

Anyone else did tests along these lines? Did your test agree or not?

Thanks,
UL