How to tune algorithm performances in computer science papers
It would be dishonest to do this without mentioning that the algorithm was tuned differently. You ought to specify what the tuning changed and how this affects the results of the algorithm.

You should also list accuracy results for the fast algorithm and speed results for the accurate algorithm. (Your probably also want some numbers for middle of the road tuning too). Not listing the "bad" results isn't dishonest, but it's bad science. If you didn't include these numbers, I'd expect your reviewers to bring it up and ask for them.