After a seemingly straightfoward 365 GTC/4 service started, it quickly cascaded into a full-on renovation project.

Photo: Snowball 1
July 23, 2020

Today, this Ferrari 365 GTC/4 looks factory-fresh. However, it didn’t look nearly so nice one year ago, when it arrived at Berlinetta Motorcars in Huntington, New York.

“It needed a general restoration, including paint, a new interior, and mechanical work,” recalls company owner Doug Pirrone. “Besides the general deterioration from time and use, it had been sitting idle for ten years before our client bought it, which only made the situation worse. But when it initially came into the shop, it wasn’t for a complete restoration. At first, we were just going to get it running and driving.”

To that end, the Berlinetta mechanics drained the old gasoline and cleaned the car’s twin fuel tanks, pumps, and lines. Next came an oil change, a new battery, and new spark plugs. That was followed by a complete renewal of the brake system, which included rebuilding the four-piston calipers and twin-reservoir master cylinder.

Photo: Snowball 2

“After we completed the initial work, it started right up, but it was only running on 11 cylinders,” Pirrone explains. “It actually idled reasonably well and it even drove okay, but there was obviously something wrong. We then did a compression test and discovered one cylinder with no compression.”

It was then that the original plan went off the rails, and a new, far more extensive project began.

FERRARI UNVEILED THE Pininfarina-designed, Filippo Sapino-penned 365 GTC/4 at the Geneva Motor Show in March 1971. The new car’s underpinnings were based on the 365 GTB/4 Daytona, but as a partial replacement for the outgoing 365 GT 2+2, it featured some notable differences, including standard power steering and Koni-supplied self-leveling rear suspension.

Photo: Snowball 3

In addition to designing them, Pininfarina built the 365 GTC/4 bodies, which were noticeably higher in quality than many of the other handbuilt cars of the era. The finished bodies were shipped from Pininfarina’s workshop in Turin to Ferrari’s assembly line in Maranello, where the cars were completed. When production concluded in 1972, a total of 505 examples had been built.

The 365 GTC/4 used a wet-sump, lower compression version of the Daytona’s 4.4-liter V12, and when the Berlinetta crew removed our featured car’s sick engine to evaluate exactly what was wrong, they discovered a larger, more unusual problem than anticipated—a not-unusual occurrence with vintage machinery. It turned out that, at some point in the past, the right rear corner of the engine block had cracked.

“It’s possible that the coolant in the block froze,” Pirrone surmises, “and the expansion caused the block to crack. It’s also possible that a broken valve caused the crack.”

Photo: Snowball 4

The crack was fairly extensive, and included part of the bellhousing. Somebody had welded the dislocated section of the block back into place, and it was good enough for the engine to run, but it wasn’t perfect.

“The line bore of the crankshaft wasn’t right, so the bearing clearances weren’t what they should be and the crank wasn’t turning entirely free,” adds Pirrone. “We had to remove the rear section that broke off and weld it back together again, taking great care to make sure it was in exactly the correct position.”

The skill required for this type of repair is extremely high, as was the time invested, which translates into considerable expense. It would have been easier to simply replace the damaged block with an undamaged casting, but since the former was original to the car, all concerned agreed that it was worth saving.

Photo: Snowball 5

“It’s very, very difficult, but possible, to find a good used block,” says Pirrone. “Alternatively, Ferrari would cast a new block for us. But either way, the replacement block wouldn’t have the correct numbers. It wouldn’t have the original stamped numbers or the numero interno, which is the unique number cast into each block in the foundry. Those numbers in this car’s original block identify it as the one the factory installed when the car was new. It’s always preferable to save the original block when possible.”

After the precision welding was completed and new cylinder liners were installed, the block was line bored and all critical dimensions, including deck height and cylinder spacing, were measured. The restored block was fitted with slightly oversize replacement pistons, as well as its original connecting rods and crankshaft.

Next, the crew turned its attention to the engine’s cylinder heads. “The castings were in excellent condition, and the valves and their seats were fine,” remembers Pirrone. “We machined the valves and seats, and reused the original camshafts after checking them and confirming they were good.”

Photo: Snowball 6

Because the GTC/4’s V12 utilizes two ignition distributors, it’s crucial to set their advance curves as close to identical as possible. To this end, both distributors were fitted with new, matched springs and weights and then tested on a distributor machine.

While Pirrone wanted to retain the look of the original Magneti Marelli Dinoplex electronic ignition, which was still working, he decided to modify its innards for significantly improved reliability. “We used MSD ignition coils and MSD amplifiers in place of the original Magneti Marelli parts,” he explains. “Unlike the originals, the MSD parts are extremely reliable and we’re able to conceal everything to retain the correct factory appearance.”

Because Pirrone had been able to drive the car before fixing its damaged engine, he had gotten a feel for the condition of the gearbox and differential. Damaged synchronizers, especially on second gear, are a common issue with GTC/4s, but this particular car’s transmission shifted extremely smoothly, and both the trans and the differential were very quiet—a good sign.

Photo: Snowball 7

Once the crew removed both units from the car and opened them up, they were able to confirm that all was indeed well. After thoroughly cleaning them out to remove old lubricants and any microscopic wear particles that had accumulated, they buttoned them back up with new seals and filled them with fresh fluid. Though the car’s single, dry-plate clutch had worked fine when the car was driven before the tear down, it was deemed sensible to install a new clutch assembly when it all went back together.

WITH THE FERRARI IMMOBILIZED for a good stretch of time while its engine was being repaired, its owner decided to have the exterior restored simultaneously. He initially planned to leave the interior alone, as it was in pretty good condition, consistent with the car’s indicated 43,000 miles. However, he soon concluded that a decent interior would look weak in comparison to a completely refinished exterior, so asked Pirrone to do what was necessary to return the cabin to as-new condition.

The Pininfarina-built body was in outstanding condition, with none of the corrosion typically found at the bottoms of the door skins and quarter panels, so the exterior rehabilitation was very straightforward. After removing all of the glass, lights, trim, and other parts, the Berlinetta crew stripped off the old paint then went over the entire body and fixed any imperfections.

Photo: Snowball 8

Once the steel shell and doors, along with the aluminum hood and trunk, were as good as they could be, high-build primer was applied and block sanded. Following sealer, the body was sprayed with two-stage urethane products from Glassurit. After paint, it was time to complete the exterior renewal by polishing the stainless-steel trim, replating the chrome pieces, installing new weather stripping, and refinishing the original wheels.

As anyone who has restored cast-magnesium Cromodora wheels knows, getting the finish correct can be quite an accomplishment. “The original finish for the wheels has a very distinct appearance,” says Pirrone, “and it’s extremely difficult to get it right. After a lot of experimentation, we devised a technique that works perfectly.”

The crew kicked off the interior renovation by removing absolutely everything and cleaning up almost 50 years of miscellaneous debris that had found its way under the carpet and behind the interior panels. Since there’s no such thing as an off-the-shelf kit for a 356 GTC/4, everything needed had to be fabricated. “It’s important to use correct materials and accurately replicate all of the original details, such as the stitch counts, thread colors, surface textures, and binding on the carpets,” Pirrone notes.

Photo: Snowball 9

The Berlinetta crew installed new insulation on the fiberglass floor pan, footwells, and firewall. The seats were disassembled then built back up with new foam and recovered in new leather. Similarly, the dash, console, door panels, and remaining soft trim parts were recovered with new materials, with a new headliner finishing off the roof.

Palo Alto Speedometer calibrated and cosmetically restored the Ferrari’s Veglia gauges. Similar attention was paid to myriad other parts, including the seat belts, switches, vent controls, the shifter’s shaft, knob and boot, steering column, and steering wheel before the interior rebirth was declared complete. The crew restored the trunk with the same care and attention to detail lavished on the interior, cutting, trimming, and installing new carpets over the panels.

With the brakes already sorted, it was time to inspect the remaining chassis parts. They were in good working condition, but after nearly five decades they looked pretty shabby, especially compared to the rest of the refinished car. To address the disparity, the crew disassembled the suspension and steering, cosmetically restored everything that was going to be reinstalled, and replaced the normal wear items with new parts. In keeping with the owner’s desire to maintain a factory appearance, all of the original chassis hardware was cleaned and sent out for replating.

Photo: Snowball 10

After many hours spread over the better part of a year, this 365 GTC/4 has been returned to as-new condition—and in some ways, it’s better than new. Thanks to the snowball effect created by that cracked engine block, this beautiful machine is ready to deliver another half century of driving pleasure.

Photo: Snowball 11
Photo: Snowball 12

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