Building a race car. Taking a look behind the scenes at how a Time Attack car has been created.
Minker 3 was conceived in 2016 as a successor to Minker 2, the Turbo Technics Sierra which had been run very successfully in sprints and hillclimbs over a 21 year life.
With the intention to run it in Time Attack as well as sprint/hillclimb, the specification had to be carefully planned. The engine had to be based on the Ecoboost 2.3, but as transmission was free it was decided to use the EVO X transmission fitted with a Pfizer 6-speed dog gear set and pneumatic paddle shift, with an active centre differential.
A suspension design would be developed to optimise geometry based around cast uprights of TT manufacture, and high braking capacity would be incorporated to cater for circuit use. The suspension would be fully adjustable.
The engine would need a minimum of 600 BHP with good torque and drivability.
Bodyshell
The Focus Mk 3 donor car arrives. This was actually a diesel, but as only the bodyshell and fittings will be needed a low-cost used example was obtained.
Custom Cages designed and built the prototype roll cage. A very comprehensive job, neatly done!
Front and rear turrets were added to allow independent camber and caster adjustment. Adjustment is by sliding plates with slotted holes.
The steering position was finalised. Revised suspension geometry meant that a bespoke rack would be required.
The engine location was finalised and engine mountings manufactured.
The shell is ready for paint, with arches modified and various brackets welded on.
Back from the paint shop. OCS Paint of Flore carried out the painting, and did an excellent job. The colour scheme followed previous generations of Sierras
Suspension
A tubular subframe carries the front suspension and steering. Space constraints meant that the design was challenging! The rack was made by Titan and subsequently modified to incorporate electro-hydraulic assistance with a remote actuator in the column.
Front suspension is fabricated from T45 tube, rose-jointed and fully adjustable.
A new subframe was required to mount the rear suspension and differential assembly.
Rear suspension is fabricated from T45 tube, rose-jointed and fully adjustable. Note also the TT cast upright, same front and rear.
Bespoke AVO triple adjustable coil-over suspension units front & rear.
Brakes
Front brakes are AP 6-pot callipers on 356mm Dia TT vented discs.
Rear brakes are AP 4-pot callipers on 324mm Dia TT vented discs.
Engine bay ready to receive the power unit.
Engine
The top deck of the cylinder block was closed to support the liners and increase strength. Mahle pistons were used with Manley Pro-series rods, and the balancer gear deleted.
Exhaust valve size was increased to 32mm with specially made nimonic valves, and the ports enlarged to suit. Inlet ports were also flowed and polished.
A cast inlet manifold was designed with ram ports and additional port injectors. Two-piece construction meant that the ports could be polished through before final assembly. The standard throttle body was retained.
Turbine entry adapter fabricated from 3.0mm stainless steel to adapt to the manifold-in-head.
Dry sump oil pump mounted with poly-vee drive belt and tensioner.
Turbocharger
A bespoke turbo was designed, based on TT’s EVO 9 unit but with 79/66mm dia wheels of TT design, high-flowing wastegate and electric actuator. The turbo is capable of higher power if needed!
Note the ported compressor shroud.
Exhaust
Exhaust downpipe made from 0.8mm stainless steel sheet.
Exhaust system (prior to catalyst fitment). System is also made from 0.8mm stainless steel sheet and silencer boxes are aluminium, making a very lightweight system.
Catalyst in position
Fuel Tank
The 18 litre fuel system runs twin pumps with a submerged and gated swirl pot. The fabricated tank was made by Concept Racing.
Dyno Running
Engine on dyno test at DTW Engines in Harlow.
MBE 9A6 engine management was selected to control the direct+port injection, the paddle-shift gearchange and the electric actuator.
With excellent mapping assistance from SBD, testing went smoothly and the power/torque target was achieved.
Engine Installation
Cooling group mounted on the front panel subframe.
Final engine bay installation.Oil tank and coolant header manufactured by Concept Racing.
The air path from compressor to throttle is kept as short as possible to aid response.
Transmission
Gearbox mated to engine.
Bellhousing modified to fit Ford block.
Hydraulic pump for centre diff.
Gearchange actuator.
Aero
Front spoiler as moulded.
Rear diffuser mould.
Rear diffuser with strakes.
Side-skirt moulding.
Race ready...
Time Attack and Speed events allow considerable freedom in the build of the cars, which adds to the challenges of the series. This also means that the build of the TT car is continually evolving. Watch this space!
