Ju 288 C
Me 262 A-1a
As you can see, Me 288 C is not faster.
But in battle, you start with different speed and on different alt. He need to take off or got air spawned a lot lower than your bomber, so instead of gaining speed, first he need to gain altitude.
And it is, in same conditions (I think we do not have in WT jet fighter slower than fastest piston aircraft, so at the end of the day, after enough time jet will be always faster than piston aircraft).