When you think of hot rods, you think of ’32 Fords and ’40 Mercs, but what about a Mk 10 Jaguar as the starting point? Not an obvious choice to most, but it was in Paul Child’s mind.
The Mark X was the top of the line saloon car built by Jaguar, originally aimed at the American market—the first Jaguar saloon to feature independent rear suspension. It utilized a wide-track version of the IRS unit used on the E-Type, while the front suspension had double wishbones with coil springs and telescopic dampers. In the beginning, the 3781-cc, inline, 6-cylinder engine with 9:1 compression was standard, though an 8:1 version was available as an option. Later the 4,235-cc engine took over and triple S.U. carburetors were fitted. Many of the domestic cars, and almost all headed for the U.S., left the factory with a Borg Warner automatic. Power assisted steering was standard.
When the owner of this Jaguar special, Paul Childs, had first seen a Mark 10, along with the E-Type, at the age of 16 in 1963, he thought he had finally witnessed what real cars could be. In later years, having owned a 1963 E-Type and a ’66 Mark X, Paul was ready for another Jag, but one with a bit of a difference.
Childs knew a few Mark X convertibles existed, and found the company who made the conversions, “Leaping Cat Ltd.” in Leicestershire, England. In 1985, he purchased one from them. The 1968 model, technically a 420G, the continuation of the Mark 10 with larger engine and minor trim changes, started life as all Mark X/420Gs do, as a four door hardtop.
Leaping Cats had converted about a dozen saloons into convertibles.
First order of business was to have a removable hardtop made. Childs knew that Jaguar had experimented with the then new V12 engine in Mark 10s, so his next step was to get a hold of one and get it souped up. A friend in England put Childs in touch with a company that modified Jaguars and raced them, and he purchased a new V12 from them that had gas-flowed (ported) cylinder heads and high-lift camshafts. At the same time, Childs’ Mark X was converted to left-hand drive.
Rounding out the new package, the suspension and brakes were uprated and a 5-speed manual Getrag was added to keep up with the new power plant. The Jag was then sent to Arthur Howlett of East Sussex to put on the finishing touches.
Finally arriving in the U.S. in 1990, the car continued to be a work in progress. A complete restoration of the body and numerous engine upgrades have brought the car into the 21st century. (Unfortunately, the electrical system remains 1960s Jaguar!) Some of the latest mods include a new rack & pinion steering system, along with the installation of an AJ6 manifold that has added about 40 horsepower.
The car that started life as a 4-door businessman’s transport with very little performance to write home about has now become a two-door rocket ship. I wonder what Sir William would think?
On the Road
After opening that very large door on the Jaguar you notice a few things out of place. First, there is a shift lever in the center console and a third pedal by your feet, and when you look up you see the sky. This is no normal Mark 10.
Turn the key and the point is driven home even more. It’s not the subdued song of a straight six, but the rumble of a V12 dumping out of twin pipes behind you. The Mark 10 was not a car you would rev the engine at a stoplight, but this one you would, even if it is just to make yourself smile.
Find first gear and start off and that wonderful sound continues to grow, shift up a gear put your foot down and you truly start to appreciate what a special car this is, it pins you to the seat because IT IS FAST!! This is not a sedate luxury sedan, it’s a beast. You won’t have to worry about getting in the way of modern traffic, they are going to have to get out of your way. You can really feel how the addition of the rack and pinion steering, vented disc brakes and coilover shocks have improved the Jag, it has a very solid feel and the steering is very precise, but that doesn’t make this an XKE. You are still in a very big car, and the chassis does have some flex to it from having the top taken off, even with the added strengthening done to it. You won’t be carving up corners on the Stelvio Pass with this one, but it would do you proud on the Autobahn or any nice piece of straight road you want to aim it down. This Mark 10 really is a British hot rod, it’s big, it’s brash, it’s fast, it doesn’t go around turns all that well, but it sure makes you feel cool. —Sean Smith
Driven Classics at a Glance:
SPECIFICATIONS
1968 Jaguar MK10 Special
Body construction: steel-bodied convertible on frame
Wheelbase: 120 inches
Length: 202 inches
Width: 73.6 inches
Front Track: 58 inches
Rear Track: 58 inches
Height: 54.5 inches
Weight: 4200 pounds (stock)
Suspension: (F) Double wishbone with coilover springs (R) IRS
Steering: Rack & pinion, custom installation
Engine: Custom, 5.2-liter, V12
Bore x Stroke: 90 mm x 70 mm
Induction: Custom fuel injection
Power: 340 hp
Transmission: 5-speed manual
Brakes: slotted discs
PERFORMANCE
Top Speed: 140 mph
0-60 mph: 5.5 seconds
Average fuel consumption: 20 mpg
VALUATION
Price at launch: $7,000
This Example: $150,000
(Stock)
Excellent: $35,000
Good: $25,000
Average: $20,000
Poor: $10,000
