The Lincoln Mark VIII comes from the factory with an electronic speed limiter built into it. The standard Mark VIII with a 3.07 rear end ratio might see 130 mph before this kicks in. On a Mark VIII LSC model with a 3.27 rear end you reach this limit at around 124 mph and 5000 rpm in third gear. Clicking on the electronic overdrive does not allow the speed to increase. If you're a speed freak a new chip will eliminate this obstacle. Earlier model Marks came equipped with a distributor that can be advanced or "curved" to increase performance. The modular DOHC 4.6-liter from 93-98 is not equipped with a distributor and the only way to play with the "advance curve" and timing is though a new computer chip. This not only eliminates the top speed limiter but enhances the low and mid-range power output as well. Superchips out of Lakewood, Florida make the chip I used. Their website is www.superchips.com/mk8.htm. The website states that the horsepower is increase by 26 on a standard Mark VIII and 29 on a LSC model. Torque is also increased by 36 and 34 foot pounds depending on the model Mark you have. The numbers might seem high but there sure is a seat of pants feel that indicates at least 20 or more horsepower. The module piggybacks onto the stock factory computer, which is located on the driver's side under the steering column. Prior to ordering a module you will need to remove the factory computer and note the code stamped on the ECU. If you have made any after market modifications to your Mark VIII, they can in most cases, create a custom chip to utilize those items. Prior to adding my Superchip, using a hand held stopwatch; I was able to clock my car in 0-60 mph sprints at 7.1 to 7.3 seconds. After the chip, I had dropped these times down to the 6.6 to 6.8 second range. My top speed has increased from the 125 mph on the speedometer to pegged out on the bottom of the dash an inch or so past the 140 mph mark. Interpolation of the tach and speedometer would place this around 147 to 150+ mph range. The chip also improves the normal around town driveabilty. Fuel economy may increase slightly if you're able to resist the temptation to use this new found power. The chip also alters the AODE transmission for firmness and shift points. You no longer have those mushy "Town Car" lazy shifts. The AODE now shifts quick and crisp to the point of chirping the tires on a manual 6500 rpm first to second shift. The DOHC 4.6-liter package is a strong package that likes higher rpm's. There are not too many after market modifications that can be made inexpensively at present. At $245 the Superchip is probably the best deal for your money if you don't want to get too radical. Try it you'll like it.