JPC added this Moroso catch can in anticipation of the transmission going south. It's connected to the vent tube and should catch any transmission fluid that wants to exit the case from the vent. | 
The computer tune was manipulated with DiabloSport Chipmaster software and loaded into the car using a Predator handheld reflash tuner. Burcham kept the air/fuel ratio conservative for the blower tune. That meant a reading of 11.2:1, a little richer than normal, as he prefers to keep them in the 11.5-11.8:1 range for maximum power. | 
While on the dyno, we wanted to see the effect of running a nitrous spray bar over the intercooler. Long story short, we saw zero gains and only a 4-degree drop on the inlet air temp (IAT) sensor. "You carry an extra 25 pounds in weight and waste a lot of nitrous for nothing," Burcham says. One reason why the nitrous over the intercooler trick didn't work could have been the fact that we utilized a twin-core intercooler that ProCharger rates up to 850 hp. |
The Predator has datalogging capabilities, and we used it to keep an eye on the IAT sensor and other parameters. Our best run produced a maximum inlet temp of 128 degrees at 6,600 rpm. The run started off at 94 degrees. The screen shown was from our baseline backup pass on the dyno and displayed a max reading of 132 degrees. Despite being 5 degrees warmer, the power remained the same. We were unable to log the IAT on the jug because the nitrous is sprayed after the MAF sensor, which is where the Predator takes the temperature reading. You can be sure the air is super-cold as it enters the intake manifold. | 
The digital box that controls WOT activation has to be set using a special technique outlined in the instructions. It involves disconnecting the ground from the fuel solenoid and having someone push the pedal to the floor. The box uses lights to show when it has been programmed to recognize WOT from the TPS sensor. | 
We went right to the 125hp setting-56 nitrous jet and 36 fuel jet. That sent our blower car straight off the air/fuel ratio chart with a Sierra Club-protesting sub-10:1 air/fuel ratio. Black smoke emitted from the tailpipes during the dyno pulls. "These systems and jet settings are designed for naturally aspirated engines that start at 13:1 air/fuel ratios and end up with 11:1," Burcham says. "With just the ProCharger, we were at 11.2:1, and this kit dropped it down 2 points like it was designed to do. It's pig-rich, but it's also safe. We can trim some fuel out of it and still keep things safe." |
The only thing that isn't totally daily driver worthy are the Bogart wheels with BFGoodrich Drag Radial meats in the back and skinny tires up front-they're fine for some and too big of a compromise for others. Some people might also object to the 4.10 gears in the rear, but honestly, they're just fine, and cruising rpm is reasonable at highway speeds. | 
"You lose a lot through the automatic, which is why we added the nitrous in the first place," Burcham says. It also caused some problems when we hit the nitrous as the converter wouldn't lock up until later in the dyno pull, throwing off the torque curve. | 
With just the blower and 93-octane, Burcham runs this car at 15 degrees of timing. Add 104-octane, and 18 degrees is used for maximum power. The addition of nitrous requires 3 degrees of timing to be removed. It works out nicely that the car is always run on 104-octane when on the jug, so one tune is good for nitrous/blower and blower/pump gas use. |
"I've leaned this car out to 11.8:1 and made 535 rwhp, but I like to keep it conservative when I give it back to its owner," Burcham says. "This is a street car first and a track car second." Max power with 16 degrees of timing (pulled back in anticipation of the nitrous) and 104-octane fuel was 478 rwhp and 446 rwtq. That's good enough for low-11-second runs in this 3,950-pound S197. | 
The torque converter lockup was killing us, and we threw in the towel after a few attempts to get it to lock up earlier. It was late at night, and we realized the extra power and torque from the nitrous was causing the engine to blow through the converter at a higher rpm than when it was just on the blower. Nevertheless, once the converter locked up in the higher rpm ranges, the horsepower reading was clear, and it showed a 70hp gain at the top and 90hp gains through the midrange. We think 548 rwhp is serious power, especially for a stock engine like this one. | |