1965 GTO Restoration
Before I bought this 1965 GTO convertible, it had sat outside for years, parked underneath a ragged tarp at Maxwell-Gunter Air Force base in Alabama. The exterior was scratched and dented, seat springs rusty and broken, and interior carpet wet and ripped. Tires were bald and wheels were mismatched. There was nothing left of the convertible top except the frame.
Someone with good intentions had tried rebuilding the motor, abandoning the project mid-way, leaving the cylinder heads and various other engine parts in the trunk. The tri-power manifold and carburetors were inside the car on the back floor.
Early GTO VIN Numbers
First and second year GTO models were an only an option on the Pontiac Tempest model, so they can be easily forged. Check the VIN of the car with PHS (Pontiac Historical Services) before buying one! You can contact them at PHS-online.com
After reading over the build-sheet, this particular car had left the factory with every performance option offered for 1965; close-ratio 4-speed transmission, 3.90 posi-traction rear axle, transistorized ignition, semi-metallic brake drums, and the 389ci Tri-power engine.
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I rented an engine hoist from a local parts house, drove it home in the back of my 1970 El Camino, called up a couple friends, and got started. In stock trim, Pontiac rated the 1965 Tri-power motor at a conservative 360 horsepower. In a properly prepared car, that was good for 14-second quarter-mile ETs. But I needed to make a little more power.
1965 GTO Body
The sheet-metal repair needed on this car was minor. The doors, quarter panels, and trunk lid were straight, and actually had (very faded) original white lacquer paint still left on them. The front end was another story.
Front Sheet Metal
Non-stock hood pins had been previously installed, leaving two unwanted holes in the hood and two on top of the radiator support. Small metal patches were fabricated for the holes in the hood and MIG-welded in.
Fender-well headers had been installed years before, leaving nasty holes in the inner fender-wells. I would have liked to reuse the headers, but they were badly rusted as well as dented on the bottom.
All of the front sheet metal had to be removed to replace the bad fender-wells. This included the hood, grille, and both fenders. This was a good time as any to go over the entire engine compartment...
I found a used radiator support, which I sandblasted down to bare metal, epoxy-primered and painted the correct 60% gloss black.
Inner Fender Skirts
After doing some research, I found that early Tempests, Lemans, and GTOs shared much of the same sheet metal. 1964, 1965, and 1966 fenderwells are the same. 1967 fender-wells had a dimple in the back to accommodate a larger power-booster, but can be used for earlier GTOs.
1965 GTO Grille
Lemans front grilles were different than Tempest front grilles, and buyers who selected the GTO option got the Lemans grille with it's center bars painted matte black. Lower grille panel and fender extensions were painted to match the exterior body color. A white-lettered GTO nameplate was mounted in the left-side grille.
GTO Headlamp Doors
In 1965, models with the GTO option had headlamp doors with blacked-out ribs. Both 1964 and 1965 GTO models came from the factory with Guide T3 headlamps.
The "6.5 Litre" fender emblems are the same for 1964-68 GTOs. They mount on the lower rear of each front fender.
1965 GTO Engine
What helped set the Pontiac GTO apart from other muscle cars of the era was the tri-power induction system: three two-barrel Rochester carburetors on a cast-iron intake manifold, each with it's own small chrome air filter.
read Tri-power Carbs and Manifold
read 389 Engine Build
Now that the motor was making even more power, it was time to do something about those front drum brakes. A popular swap is using 1968-1972 A-body brakes on the earlier 1964 to 1967 models.
read Drum to Disc Brake Conversion
1965 GTO Exhaust
Although tempted to buy reproduction free-flow cast-iron manifolds, I decided to get the best performance headers I could find, which at the time were Hooker Super-Comps (there's not much that sounds better than a high-compression V-8 with headers).
Original tail-pipe diameter on 1965 GTOs was 2-1/2", but they were not available when I restored this car. Tail-pipes in smaller-than-stock 2-1/4" diameter were available, so I went with those. The left-side intermediate pipe was available, but the right-side wasn't. So, I bought two left-side intermediate pipes, cut one of them in the middle, slipped on an exhaust coupler, rotated the back end 180 degrees and welded it up. For mufflers I used a pair of free-flow Walker Dynamax units.