Goku got an insane power boost on Namek, all thanks to his Zen Kai. Goku's power against Guinea was 90,000 and after healing it jumped to 3 million, a boost of over 33 times. For reference, before healing, he would have maxed out at 1.
8 million with Kaokens 20. He got so strong that his base power was nearly double of what his former ceiling was.
