The fans of the LT1 Brougham always complain about how slow the SOHC four-six Town Car is. It's not that bad at all! In all reality, a stock LT1 Brougham will do naught to sixty in about 7.7-8.2 seconds, and the 1/4 mile in 15.6-16.2 seconds. A 4.6 Town Car will do it in 8.5-9 seconds, and 16.5-17.0 seconds. That's not much worse at all! And, like the LT1, the SOHC 4.6 has loads of aftermarket!
If I'm not mistaken, the 4.6 will get better mileage, usually by about 3-4 in city. My old LT1 Roadmaster would struggle to get more than 14MPG around town, and from all the reviews I've read, and all the TC owners I've talked to, the TC gets around 17-18 around town, and 26-28 on the open road. The LT1 will get about 25-26 on the open road, the best I ever got with my Roadie was 21MPG, but something wasn't right with that car..