Gravity does warp space.
You could get a hell of a gravitational boost from a black hole.
I read about that a while back how you could go into the future by using a black hole for speed, I forget the exact years but it was pretty insane - Something like a years travel and when you came back to earth it would be 100 years in the future. I would do that! without thinking twice Guaranteed no Nancy Pelosi around when you came back....Unless she cloned herself then I would be like Charlton Heston at the end of Planet of the apes “You Maniacs! You cloned her! Ah, damn you! God damn you all to hell!”