V=(1/3)hpir^2
d/2=r
2.75/2=1.375
to make volume 4 times more
multiply height by 4 or multiply radius by 2
example
find current cup volume
V=(1/3)2.75pi1.375^2=2.2057291666666pi
if we times height by 4
3.5*4=14
V=(1/3)14pi1.375^2=8.822916666666666666pi
if we times radius by 2
1.375*2=5.5
V=(1/3)3.5pi5.5^2=8.822916666666666666pi
we can show it is 4 times by
8.822916666666666666pi/2.2057291666666pi= 3.99999 close enough
dimentions are
diameter of 2.75in and height of 11in or
diameter of 5.5in and height of 3.5 in