Often in the quest for knowledge, the journey to your destination is more important than your arrival. Lincoln Tech's "bolt-on" Z did deliver on its low-12 second potential, but the events that led up to meeting this goal were much more enlightening than the final results. We're going to tell the whole story, potholes and all.
To recap, Lincoln Technical Institute's Columbia, Maryland, automotive campus "inherited" a 100,000-plus-mile '99 Z28 Camaro. It weighs 3,435 pounds without a driver, including a full complement of working accessories, like leather power seats, A/C, and a kickin' stereo. At the conclusion of Part I, the student techs had equipped it with a set of Hooker long-tube headers, a Flowmaster American thunder exhaust, Alston Frame connectors and control arms, Nitto Drag Radials, a Quartermile Performance Air Box, Rush air filter, 4.10 Richmond gears, an Auburn Pro Posi, and Moser Axles. The Camaro used these bolt-on pieces to great success when it posted a best of 12.85 at 110.03 mph with a 1.94 60-foot time. The Camaro was still traction-challenged, so the students installed an Alston adjustable torque arm with 2 degrees of pinion angle. The Alston bar has a preferred solid mounting to the transmission tunnel rather than the standard rubber isolated transmission mount.
At this point of the project, scientific method gave way to the stark reality of bad weather. Limited available track time made it necessary to bolt on the balance of the available equipment as quickly as possible. The techs now simultaneously installed their SLP-supplied Z06 intake, mass air flow (MAF) sensor, and a BBK 80mm throttle-body and returned to Capitol Raceway in Crotton, Maryland. These modifications made nary a difference as the Camaro pulled down a best of 12.79 at 110.34. The 60-foot times did improve to 1.88, but the new induction package had made no appreciable increase in power.
Undaunted, the students knew that making hp was about proper combinations. They realized that Z06 Corvette camshaft timing had at least 0.030-inch greater gross lift and filed that away for a future fix.
Now the real flogging began. TCI supplied one of its proven 10-inch Street Fighter torque converters. The general consensus was that this would allow the engine to flash to a higher rpm, thereby taking advantage of the intake's true potential. Full of anticipation, the students again drove to Capitol Raceway. Upon its arrival, the Camaro illuminated a check engine light.
An interesting development in modern automotive technology is the various "open loop" or "limp home" modes of operation. The Electronic Control Module will let a car appear to run flawlessly, but not to the point where it can be damaged. The Camaro felt as strong as ever, but one lap showed it was not up to par, running 12.84 at 107.85 with a 1.88 60-foot time. A return to the campus and a meeting with the OBD II scanners showed numerous high-speed misfires. This was accompanied by the embarrassing revelation that the original spark plugs had never been replaced (they looked OK when we put the headers in). A new set of Autolite Platinum Plugs went in, and at this point a decision was made to replace the 4.10 gear with a Richmond 3.73 gear. Conversations with various manufacturers led the students to believe the stock E.C.M. programming might have logic conflicts with the deeper rear gear. The students used a Hypertech reprogrammer for fuel shut off, gear ratio, and tire-diameter adjustments. The Hypertech unit would not improve the fuel and timing settings on the now-non-stock '99 Z. Frankly, with the 4L6OE's 3.06 First gear, a 4.10 probably wasn't necessary.
During this down time, the students also swapped the stock 1.70:1 rocker arms for a new set of Comp Cams 1.75:1 Pro Magnum roller rockers and the corresponding valvetrain (springs, retainers, guide plates, and pushrods). The new rocker would only add about 0.015 lift, but this was as much rocker ratio as the Comp Cams technical people felt the stock valvesprings would stand. While the stock LS1 valvetrain is very good, keep in mind that the Camaro had over 100,000 miles on it, so a decision was made to replace it all. Note to all fourth-generation F-body owners: Do not attempt an engine-in-car valvespring replacement without a More Performance LS1 spring tool (PN 880SCT).
Back at the track, the students' bad luck continued! As the Camaro entered the pits, it lit a code light again. A decision was made to lap the car anyway. Amazingly, with as little as 15 degrees total timing due to "open loop" status, the car laid down a best e.t. of 12.73 at only 107.93 mph with another best 1.77 60-foot time. As Lincoln Tech Motorsport coordinator Clement Trusty related, "It was much calmer so it hooked better, but the 2-3 shift was almost not there (remember this). It was definitely down on power in the second half." A return to campus revealed a knock sensor malfunction code. Sensors do go bad at about 100,000 miles. But good techs are trained not to blindly replace sensors and control devices, opting instead to check for flaws. A thorough, half-day-long wire-shaking, probing, and inspection of everything related to the knock sensor preceded the removal of the Z06 intake. This revealed a pinched intake gasket, which had leaked coolant around the front sensor, requiring the gasket and sensor be replaced.
Back to the track, we forgot all past anguish when the Z28 laid down a 12.46 at 111.24. Even more encouraging was the 1.85 60-foot time. We managed one more pass with near identical times before the rains came again. The improved e.t. and mph with the slower 1.85 60-foot times led the students to believe that their 50-plus-pass drag radials were done. The next week the car arrived at the track with a new set of Hoosiers 26x9.5x16 DOT tires. This new tire offered less footprint but more of a slick-type sidewall. The Camaro responded with a 12.44 at 110.93 with a 1.76 60-foot time. The young techs were agonizingly close to their goal of a full second e.t. improvement. The Z's poor weight distribution (56/44) made them re-examine their suspension setup. They bolted on an Auto Fab Racecar coilover rear suspension conversion kit for third- and fourth-generation F-bodies. The kit allows the installation of QA-1 12-position adjustable shocks and 130-pound springs.
At the track, the students softened the stiff initial setting until the Z28 delivered a 12.35 at 111.94 with a 1.68 60-foot time. Unfortunately, after several attempts nearly duplicating these numbers, the Camaro, which had responded so magnificently, would now only occasionally go into and stay in Third gear, thereby closing this chapter of the project.
However, this group of young technicians is not ready to quit. Now that they have gone "into" the transmission, they may as well "freshen" the engine, too. How many non-power-adder, pump gas, 10-second street-driven cars do you reckon are out there?
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