Muscle Mustangs & Fast Fords
Rear Differential Upgrade - Project Silver Stealth Stang
Project Silver Stealth Stang Accelerates Quicker Thanks To Larger Gears, An Aluminum Driveshaft, And A Looser Torque Converter.
"I drove it out softly because I knew the tires would spin easier with the 4.10s," states Miele. It only took two runs to crack off the 13.62. The first hit was a tire-spinning 13.75, which caused Miele to adapt his driving style by rolling into the throttle a little softer on the follow-up pass. He backed up the 13.62 with a 13.65. One of the important factors to getting a car to hook in cold weather is a hellacious burnout, especially with Nitto 555 tires. These aren't drag radial tires, but they respond well to a good smoking. We found that when Miele doesn't do a good burnout, the 60-foot suffers and the tires break loose on the gearshifts.
Our car picked up three-tenths from our previous best, but when you factor in the weather, we feel that adding 4.10s and the aluminum driveshaft was really worth around 2.5-tenths or so. Acceleration is the name of the game and these two simple modifications reduced our dragstrip times without us adding one horsepower under the hood. The great thing about these mods is that the cost is reasonable and they are easy to install. If that was easy, then our next upgrade is going to be even better. In addition to the lighter driveshaft and larger rear gears, we decided to swap in a looser torque converter from Pat's Performance Converters. This would allow the engine to jump right into its powerband and get near peak torque when Miele romped on the loud pedal.
A torque converter is simpler than it is perceived; it's essentially a fluid coupler connecting the engine to the transmission.Transmission fluid is pumped through the converter, and as the engine spins the backside (which happens to face forward), it rotates the pump that pushes fluid through and turns the turbine, and a stator controls the fluid returning from the turbine to the pump. The converter turns the input shaft that goes into the transmission and the vehicle is thrust forward (or backwards). The stall speed is 2,800 rpm, far looser than the stock which was 2,000 rpm. The higher stall speed helps the engine get into its peak torque range quicker and multiply it. That means quicker and faster times.
Due to the weather, we were unable to get the torque converter tested at the track. The Nitto tires bark for mercy now when Miele gets on the throttle hard at the stoplight, which didn't happen with the stock converter. Before the P.P.C. torque converter, he was able to drive it out fairly aggressive. Now the hides just squeal and burn rubber, even with the slightest hint of a jump on the gas pedal. Seat of the pants feel, it is definitely way quicker than before, and we think 13.40s, or even 13.30s, isn't out of the question--not bad for a near 160,000-mile ride.