Marcos gets major revamp

Marcos has heavily revised the TSO coupe, resulting in 149 enhancements as wide-ranging as improved forward visibility and a lighter chassis.

So far we've only driven the car in pre-production form, but full production of the TSO GTC has now begun and the car goes on sale this month (August), priced at £49,950. An 'R/T' version with a pair of lift-out targa roof panels is also being offered at £53,950.

The scale and depth of the changes in such a comparatively short timeframe can be attributed in part to Marcos’s adoption of the latest Computer Aided Design (CAD) equipment. Marcos Engineering MD Tony Stelliga explains: ‘We made a huge investment in CAD equipment up front and that’s now beginning to pay off.’

Stelliga is also keen to ram home the message about how quality was a critical part of the improvement process. ‘The new production body is made of dual gelcoat foam core GRP that comes to us as smooth as steel, meaning that there’s no sanding. This means it looks fabulous when it’s finished and substantially reduces the production costs. Now we’ve reached the production phase I’m refusing to sign any purchase orders for filler!’

The new bodyshell is also 38 per cent stiffer than the prototype version and 14 per cent lighter. During the lay-up procedure the shell is impregnated with 58 threaded brass pick-up points to ensure it sits very accurately on the chassis - if the pick-up points don’t align then the shell is rejected. The mating of those two assemblies doesn’t happen until the end of the production line to prevent potential damage to the shell during the build. For the same reason the rolling chassis is fully assembled before being joined to the body to eliminate the possibility of the bodywork cracking at stress-points as beefy component assemblies are added to the chassis.

That spaceframe chassis is fabricated by Prodrive from laser-cut steel tubes and is 11kg lighter and nine per cent more rigid than the prototype’s. The front end of the chassis is now tougher than before and the design of the front suspension has changed and includes new in-house-designed aluminium uprights. A Group N Subaru Impreza steering rack is claimed to provide ‘911-grade turning performance’, and Stelliga says that ‘the rack is expensive to buy-in but worth it for the steering precision’.

Prodrive has been responsible for a chassis set-up that now includes a re-engineered rear differential carrier to improve its behaviour during cornering. Traction control is currently under development.

While the production TSO retains the prototype’s Corvette/Monaro-sourced LS2 V8 drivetrain, a lot of work has been done on cooling to help bring the power up at high speeds. A carbonfibre ‘tongue’ in the front air-scoop rams air into a sleeved tube that feeds directly into the plenum, and because it’s insulated from under-bonnet heat, it feeds the engine air that is cooler than the ambient air temperature.

In standard tune (and with Marcos’s own induction and exhaust systems and remapped ECU) the 6-litre V8 produces 420bhp, while the ‘Performance Pack’ option gives you 462bhp. The latter’s power gain is thanks to a remapped management system and higher lifters for the valves. Stelliga boasts that ‘the car is fantastic in terms of its performance’, thanks to a 417bhp per ton power-to-weight ratio. Claimed figures for the 1125kg Marcos in Performance Pack form include a top speed of 185mph, 0-60mph in 4.1sec, 0-100mph in 8.5 and 0-100-0mph in 12.9. In fourth gear the TSO is said to zap from 50-70mph in 2.1sec.

In response to criticism of cabin space, the interior has undergone a number of changes. An electrically adjustable pedal box increases legroom by 4in, there’s an extra 4.5in of footwell space, lower seats add 2.5in to the headroom, and the gearlever has been moved forward to make it easier to use.

Marcos has also announced details of a dealer network comprising a mixture of new and established faces and a spread that covers most of England, but not Wales or Scotland.

Although Stelliga has plans to sell the TSO in other markets and is investigating a stateside foray, he wants to see how the car does in the UK first. ‘You have to do well in Britain before you do well anywhere else,' he says. 'This is the toughest market to convince and crack.’