5.0 Mustang & Super Fords
1989 Ford Mustang LX - Fox Buildup
Taking An '89 LX Into The 12-Second Zone On A Stock Engine
At the track, things didn't go exactly as planned. The first pass was a 4,000-rpm launch with massive tire spin: 13.29 at 103.2. The second and third passes had different launch techniques with the same result: 13.29 and 13.31 with a best 60-foot time of 1.89.
The handling felt a bit sloppy, and we knew something was wrong. We took the car home and put it on jackstands to search for the problem. Sure enough, the driver-side lower control arm had half of the front bushing literally hanging out of the torque box, which explained the popping and skittishness we experienced on the launch.
A quick phone call to our friend Jeremy Martorella at UPR Products remedied the problem. We replaced the existing weight-jacker lowers with UPR Pro Series lower control arms. There are several different variations available, and we chose to run the Pro Series lowers with spherical bearings and factory sway-bar mounts. While we were at it, we chose to install UPR's Pro Series double-adjustable upper control arms as well. The arms bolted in without any hassle and radically altered the handling. The car transferred weight much more smoothly on the street, but the real test took place on the dragstrip.
Since test 'n' tune at our home track was still a few days away, we sought insurance for our quest to reach the 12-second zone with MAC's Air Chamber mass air system. It's a relatively new setup, basically a cold-air kit with an integrated mass airflow sensor. The filter is a washable conical design with a plastic bell inside to direct the air smoothly into the meter. The aluminum tube that runs to the throttle body doubles as a 76mm housing for the mass air sensor. We removed the electronics from the factory sensor and installed them into the new housing.
It only took 15 minutes to get the air chamber up and running. The result was a good news/bad news situation. The butt-dyno reported a noticeable increase in power, but it came at a price. There was so much more airflow with the new system that it could really use a fresh tune. Even using the factory 19-lb/hr sampling element, the new meter caused some cold-start issues, but there'll be no computer tuning until we install the Series IV PMS upgrade from Anderson Ford Motorsport.
Were the changes enough to enter the coveted 12-second stock-motor zone? It took eight passes to find out.
The first pass was a 4,000-rpm clutch dump that resulted in massive tire spin in First and Second gears and another 13.3X. Over the next two passes, we discovered that the BFG Drag Radials like to be smoldering on the launch. Initially, we couldn't launch at anything over 3,500 rpm without spinning. White-smoking the tires outside the water box made a noticeable improvement. Our second best 60-foot of the night was a 1.76, popping the clutch at 3,500 rpm (13.02 at 103.92). On that pass, the car shook the tires.
We thought about it for a minute and decided that whatever else happened, we weren't going to destroy my daily driver just to pick up another 0.03 second. We decided to slip the clutch, but not a huge clutch slip like the street bikes do. We basically just let out the clutch like you would during normal street-driving when you're not on the throttle; slow and smooth. All of a sudden, the car was living in bog city: 3,500-rpm bog; 4,000-rpm bog; 4,500-rpm bog; 5,000-rpm bog (13.01 at 103.46, another 1.76 but this time with a smooth launch). By that point, complete strangers were approaching us in the staging lanes, encouraging us to get the last 0.02 we needed to make the project a success. I told Editor Turner we'd get a 12-second timeslip without digging into the motor, but time was running out and the pressure was on.