I agree with everything Bafbrian says about the B16 & LS trannies.

I use to have a B16 tranny on my LS/VTEC & now running an LS tranny. I definitely get about 30 MPG now compared to 25 MPG before and it's now quieter at cruising speeds on the hwy but yeah when I mash the gas it's not as responsive as it use to be.