[AstralStorm]

No, much higher, because of extra engines and more plumbing.

Starship is already pretty marginal of an upper stage and it's fired early. More marginal than old Space Shuttle, but cheaper to refurbish.

[rbanffy]

OTOH, the weight of the rocket grows mostly linearly (it's essentially a skin around propellants), the number of engines grows with the square of the diameter and the fuel volume grows at a cubic rate, so the engines can burn for longer (at some point, aerospike engines will become practical).