You can't back up the track at Englishtown because you'll run into the overhead tower and the sound barrier concrete wall. You can't extend the trap more than 20ft without hitting Pension Rd.
What could be done, though I don't know how well it would work, would be to construct a 45-degree left turn with enough banking to guide a car that gets past everything else onto the field that runs parallel to Pension Rd. That would give a few hundred more feet stopping room.
Englishtown top end:
http://www.bing.com/maps/default.asp...shtown%2C%20NJ