Dave shifts at approxmately 8,600 rpm using the air-shifter button on the steering wheel. He doesn't use the tach because he prefers to shift by ear, just past the 330-ft cones. At the traps, the tach is showing about 8,000 rpm and Dirty Bird is doing close to 213 mph. Dave pulls one of the Stroud chutes just prior to the finish line so it hits just after. He then pulls the fuel shutoff, hits the kill switch, just touches the brakes, and aims for the turn off. "If I hit both chutes, it'll jerk my eyes out my head," he jokes. "Once I packed my own chute and it didn't come out, so I don't do that anymore."
Regarding the current combination, Dave says, "The car could use a lot more gear and converter to get to 9,200 rpm at the traps, but for now, we have a conservative and consistent setup."-TD
1. Pre-Race Checks In The Pits
Fill oil and fuel
Crank without spark to get oil pressure up
Fire once to make sure nothing is leaking
Check valve lash with engine warm
Set tire pressure just before pass
Two crew members strap in driver
Turn the air and the electric on
Make sure the pins are out of fire bottles, pin is out of the parachute
Set wheelie bars down
2. At The Line
Make sure track is clear
Roll close to water box
Start engine
Do burnout
Then back up in the tire tracks
Stage
Make sure everyone is clear
Go
Engine Prep
Since this is one of the most powerful Pontiac-based engines out there, we were curious about the assembly and overhaul that goes into it. Engine builder Jim Lehart explained.
For the first few passes, they were disassembling the engine for diagnostics and learning where adjustments needed to be made via the component wear. "We were looking for wear marks on pushrods and rocker arm tips, and checking the bearings-anything that might be getting beat up, Jim says. "Since no one has built a motor like this, we are on a constant learning curve so we take it apart more often than normal."
The width of the rod bearing...
The width of the rod bearing is being measured. "We can tell which cylinder was lean by the distortion on the bearing," Jim says.
Here we see a rod and piston...
Here we see a rod and piston being assembled with buttons, which are used in place of snap rings for two reasons, Jim says. The first one being ease of assembly and disassembly and the second is because the pistons will actually grow and the aluminum buttons allow the wrist pin to move without binding. These are needed for blown alcohol and nitro engines.
Here is the assembly, ready...
Here is the assembly, ready for installation.
This is the Jesel Shaft-Mounted...
This is the Jesel Shaft-Mounted Rocker System for the Tiger Heads. They're 1.9:1 intake and 1.8:1 on the exhaust. (Note the extreme offset of the intake rockers.)
These massive intake ports...
These massive intake ports are the secret to making the big power necessary to carry the Pontiac into the mid-6s.
David fabricated this lower...
David fabricated this lower intake manifold specifically for this engine and it allows the use of a 14-71 blower. Shown are the injector nozzles as they're inserted into the intake manifold. He comments, "The design of the intake has balanced flow, so very little adjustment is needed in the port nozzles to make the combination work well." -KD