Larry Navarro's 455 Trans Am

Larry Navarro's 1979 Trans Am didn't come this way from the factory and that's a real shame. Holding up that T/A 6.6 shaker hood scoop today isn't the original T/A 6.6 400 but a slightly modified 455. According to Larry, who purchased the car from the original owner in 1989, the car is a real blast to drive on the street and a handful to drive smoothly at the strip. Most 455s we see today are mated to a THM because it transfers power to the rear very smoothly. However, Larry handles gear selection himself through the car's original 4 speed Borg Warner Super T-10 transmission. Larry freely admits that he hasn't mastered the launch at the strip yet. To that we decree, "practice, practice, practice!"

Technical Data
Engine Block: 1975 Pontiac 455, .040 over, 2-bolt
Bore and Stroke: 4.15" x 4.21"; + .040" over, 468 cubic inches
Heads: Stock '72 455 HO 7F6 , stock valves, springs, bronze guides, teflon seals, 7/16" screw in studs
Rocker Arms: Harland-Sharp roller rockers, 1.5 ratio
Crankshaft: Stock, balanced, oil holes chamfered. ARP main cap studs
Rods: Stock, reconditioned, magnafluxed and balanced, beams polished, ARP bolts
Pistons: TRW .040" over with Butler lightweight wrist pins, ductile 1st/ moly 2nd rings
Bearings: All bearings are Clevite 77
Timing Gear and Chain: Double roller, 3 key way
Gaskets: Fel Pro engine set, Felpro header set
Camshaft: Custom grind Comp Cam; 288 duration, 237 degrees @.050" intake/exhaust; 111 degree LSA; .488" lift intake/exhaust with 1.5 ratio
Intake Manifold: HO factory aluminum intake, stock, HO Racing heat riser block--block off kit
 Carburetion: '79 TA 6.6 Q-jet, rejetted and metered, #72 jets/41 rods primary; CE rods secondary, slotted air valve plates
 Fuel Pump: Holley #12-837, stock fuel line from tank, Earls AN-06 braided fuel line and fittings from pump to carburetor
 Exhaust: HO Racing headers; "Tri-Y" round port #HR-64, ceramic coated in and out; 2.5" 2-chamber Flowmasters with balance tube and mandrel bent tail pipes
 Ignition: '79 TA 6.6 HEI, stock with Accel 300+ 8.8 mm wires #7051, AC R-44 plugs @ .045 gap; initial timing set 14-16 degrees, total set to 34 degrees
 Oil Pump: Melling M54DS, 60 psi; hardened drive rod
 Transmission: Stock 4 speed Borg Warner Super T-10, 243 1st gear, Centerforce II clutch, steel flywheel
 Rear End: Stock 8.5" 10 bolt limited slip unit with 3.23 gear
Suspension / tires: Firestone Firehawk 295/50-15 on the street; McCreary G60s on the rear at the strip with 15-20 pounds of pressure depending on track conditions.
Vehicle Weight: 3815 pounds with driver

Performance: ETs range between 13.20 and 13.46. Best ET at Houston Raceway Park was 13.20 @ 107.6 mph; 60' times at 2.15 seconds.

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