By the time the S.A.M. Camaro had made it to the mid–11–second range, it had suffered a number of drivetrain failures.
The sticky tires and traction enhancements enabled, Judson Massingill to put most of the LS1’s power to the ground,
flushing out any remaining weaknesses in the drivetrain. The rear axle had been rebuilt three times before it
was finally replaced with a KTRE 12–bolt assembly, but the clutches—a known trouble with LS1 cars—couldn’t
withstand repeated 6,800–rpm launches. Switching to a McLeod adjustable assembly, including the master cylinder
(PN 139001), adjustable throw–out bearing (PN 16505), and adapter (PN 129051), resolved all clutch issues.
Installation required re–drilling the flywheel with a Ford–style pressure–plate bolt pattern. The car is driven
at 1,700 pounds pressure and raced at 1,200 pounds.
Drivetrain Upgrades
Before doing further modification, the team addressed several drivetrain issues.
The 12–bolt rear had cured the biggest initial shortcoming, since the stock 7.62–inch 10–bolt had
failed three times, but once they began applying serious traction, other weak links began to
reveal themselves. A common complaint among LS1 racers is that the factory clutch (and even some
aftermarket upgraded versions) can’t handle track abuse with sticky tires. The S.A.M. Camaro
experiences brutal launches, followed by 6,800 rpm powershifts, so clutches were being annihilated
and synchronizers in the T–56 had to be replaced every 30–40 runs. Though the T–56 never broke,
they retired it in favor of a Jerico four–speed "road–race" gearbox. To approximate factory specs,
Jerico filled the box with 2.70–1.69–1.27–1.00 ratios, and the S.A.M. team put it behind a Lakewood
blow–proof bellhousing to provide insurance while facilitating the mating process. Now a McLeod
adjustable clutch and the requisite adjustable throw–out were installed. This cured all of the
clutch ailments and gave them the advantage of being able to tune the launch characteristics.
With the clutch and rear axle sorted, power transfer was becoming efficient, though this would have put even
more strain on the stock T–56. Though it didn’t grenade, it did require new synchros after every 30 to 40 runs.
The team could have continued this routine, but with even more power anticipated, they installed a Jerico four–speed
road–race box. Student Joe Huneycutt handled the installation, which appears nearly factoy, save for the small
reverse lockout release cleverly tucked between the console sections. Though not as smooth as the T–56, the car
is street–driven with the Jerico.
