I would say that you will be okay. With DL now in terminal A, DL & NW are at opposite ends of the airport. That said, Logan is not really that big a place- just cramped.

If there is not an airside bus to terminal E, go outside terminal A and get on the Massport shuttle bus- white with a blue stripe, number 11. You could probably also hop on numbers 66 (dock) or 77/88 (parking) since they also stop at all 5 terminals.

If all else fails, I believe you could also walk through Central Parking to terminal E, which is a straight shot- would take about 10-15 minutes.