A 427 cubic inch LS1 rests...
A 427 cubic inch LS1 rests nicely between the strut towers. The block received Darton sleeves to safely widen the bore to a stellar 4.125 inches. It's set up to perform as a naturally aspirated monster and has enough torque to show Keith the sky on every launch off the transbrake. The engine is held down by motor plates and a midplate for the transmission. He hasn't dynoed the current engine setup, because Keith doesn't believe in dyno numbers in a big-stall automatic car. "I have always done my tuning at the track and on the street. The big converter won't give an accurate reading of the true power," he states.
The original aluminum LS1 block was the starting point for the 427. It was bored out to accommodate 4.125-inch bore Darton Sleeves and custom-built JE Pistons with coated skirts. The pistons use Hellfire Dykes-style piston rings from Sealed Power because they reduce friction, which frees up horsepower.
Fortifying the rest of the bottom end are 6-inch forged Eagle rods and a 4.00-inch stroke Lunati crankshaft. A Melling oil pump makes sure all the bearings are properly lubricated, a windage tray reduces oil whip off the crank to save a few ponies, and a Moroso pan holds the crude.
The solid roller cam from the previous motor was too extreme, even for the lofty goals Keith had set. He chose an "appropriately sized" hydraulic roller from Comp that he didn't want to go into too much detail about. "It measures around 265-degrees of duration and about 0.660-inch lift." He adds, "Greg was able to achieve a respectable level of streetability with the radical cam, yet it sounds vicious at any rpm." Manley valvesprings, Comp hardened pushrods, and factory 1.7-ratio rockers try to keep up with the radical valve events.
A cool stance is everything....
A cool stance is everything. In this case, it's functional, too. The complete suspension system is set up to maximize the T/A's racing potential. QA1 front springs and a set of generic rear lowering springs lower the ride height for optimal weight transfer. A pair of 325/60-15 Mickey Thompson Drag Radials is mounted to 15x10-inch wheels that mimic the front design and have a 3 1/2-inch backspacing.
After a false start with another set of heads, out of sheer frustration with the length of the buildup process, he threw on a set of factory 862 5.3L truck heads. The stock 1.89-inch intake and 1.55-inch exhaust valves are retained. Compression is 13.5:1, so the idea of pump gas is thrown out the door, but 100-octane keeps the engine happy and ping free.
A custom Beck Mechanical Sheetmetal manifold and an Anti Venom 95mm throttle body were employed, but since the Beck intake was matched to the previous cylinder heads, Keith matched them himself. "This is far from an ideal setup, but the car is running better than it has ever run, even on the nitrous," he claims.
Fuel is delivered via an Aeromotive A1000 Eliminator pump into SVO 42-pound fuel injectors. The mass airflow sensor was taken out and the LS1 now uses a speed density system that's tuned by Greg. A set of MSD coils and wires feed spark to the NGK TR55 plugs.
To tame the sound of the huge cube motor, Keith built his own custom exhaust, beginning with a set of 1 3/4-inch stepped to 2-inch Kooks headers with 3 1/2-inch collectors. From there, a catless 3 1/2-inch Y-pipe leads to a Magnaflow cat-back. The decibel levels are manageable, and it doesn't garner any unwanted attention from the law. "Aside from having no cats, the car is fully street-legal. My wife even drives it. I just had to teach her how to use the shifter," he says.
One of the coolest features...
One of the coolest features of the Fourth-Gen Birds is their round A/C vents. Since the A/C compressor was taken out to save weight and reduce parasitic loss, Keith gave his Auto Meter gauges a nice, snug home. He can monitor the temperature of his Turbo 350 transmission as well as the fuel pressure being pushed from his Aeromotive A1000 Eliminator pump.
Body
This Pontiac's appearance garners much attention. The factory WS6 hood was replaced with the more aggressive Suncoast Creations Ram Air hood that incorporates a K&N filter airbox and a cowl heat extractor.
Aldren Rodriguez of Sicbu Body Works in Tampa sprayed the Trans Am with two coats of Sherwin Williams satin Navy Blue Metallic. "I wanted to try something different with the paint. It actually gets more attention now than when it was shiny. It's been awhile, and I'm starting to miss my shine, so I think I'm going to spray it again," Keith says.
At The Track
With the Pontiac running stronger than ever, Keith takes it to the track as often as possible. In the eighth-mile, he's posted a best of 6.41 at 106 mph leaving off the transbrake at 4,500 rpm while shifting at 7,100 rpm. He runs in the 6.50 Class and True Street at NMCA events where he competes against "trailer queen" drag cars. At a 3,780-pound race weight, it's no feather-lite. He keeps his tire pressure at 40 psi up front and around 20 psi in the rear.