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.....manifold, that hooks up to the standard system. From here, the charged air passes from the turbo, along a specially cast intake manifold and then into the standard carburettor. The carb itself features only minor modifications in the way of machined throttle spindles, to prevent fuel leakage under pressure and a slight re-jet to richen up the mixture. A specially machined plate sits under the carb, to which the cast inlet manifold is bolted.
To handle the ignition under boost conditions a Micro Dynamics management system has been used in the past, but this has now been replaced by a Pace Products developed pressure retard distributor that is a more simple solution to the problem of controlling engine knock.
A high pressure fuel pump is incorporated along with a fuel regulator and this senses changes in boost pressure and adjusts the mixture accordingly. This device ensures an even and correct fuel delivery at all times. Other ingredients include a turbo boost gauge, under-bonnet heat shielding, harder plugs and high temperature ignition leads.
Out on the road, this extra boost breathes new life into the ageing crossflow and in doing so completely transforms the XR2 from a tame sporting variation into an extremely exciting and exhilarating package. Top speed goes up to around 110mph at around 6,200rpm whilst the 0-60mph figure drops significantly from 10 seconds to 8 seconds dead. A figure that is not to be sniffed at for a 1600cc vehicle in full road trim. Being fairly light and well sorted in XR2 guise, the car delivers the power to the ground reasonably well, albeit with lots of wheelspin.
Torque steer makes itself present as you change from first to second and likewise from second to third. This is manageable in the dry but presents more of a problem in the wet due to the extra power available. With around 23bhp extra over the standard 84bhp figure, this is a vast increase to inflict on a car without making any modifications to the handling department. Certainly the car needs to be tied down to the ground more, as it is prone to wander and lacks directional stability when pressing on hard. On more than one occasion we were nearly caught out due to this deficiency. It is difficult to put your finger on the problem itself, perhaps the chassis simply isn't designed to handle such a power increase, but whatever the reason it detracts from the overall driving pleasure. Certainly a good start would be to fit the Ford RS suspension/handling kit, although this would then add extra cost on the total price, but overall we feel it worth the extra outlay.
Brakes are as per the standard car and by way of contrast, we found these capable of handling the extra power. No doubt the fact that the fronts are ventilated discs, helps matters considerably.
Externally, the only differences between the Lumo 105T and the standard XR2 is a decal on the rear hatch and likewise small orange and gold turbo badges on both front wings and hatch.
Inside, it's standard XR2, apart from a dashboard mounted boost pressure gauge.
Overall, we all liked the kind of performance that the car offered, but felt that the suspension and handling could be greatly improved to make it a more enjoyable and safer package - even if it meant turning down the boost a fraction. AK
Technical Viewpoint - Lumo 105T
The Lumo Fiesta has been turbocharged with a Pace Products kit, and underneath the bonnet the layout is logical and clean.
The special cast exhaust manifold is cleverly designed to bring the turbocharger assembly as close as possible to the intake mouth of the carburettor, thereby minimising the turbo-lag. The carburettor used is a Weber DFT6 twin choke. Looking at the power and torque output of the engine I see that maximum horsepower occurs at 5,500rpm and reaches a total of 107bhp at the front wheels; this against the 84 obtained from a standard car. Maximum torque occurs at 4,000rpm and is 128lb/ft as against 93 on a standard car. However, that doesn't tell all the story as, even at 2,500rpm, already 118lb/ft is present and that largely accounts for the simply phenomenal acceleration that the little car displays. A typical 0 to 60 time of 8.0 seconds is a fast time by anybody's standards.
On this car the air is sucked into the turbocharger via the original car's air filter, which is now displaced somewhat over to the left hand side of the engine bay. The air is then carried in to the turbocharger and out the other side, across the rocker cover, and there pressure feeds the carburettor. This particular so-called blow-through arrangement always has been superior when it comes to reducing lag. The use of the specially cast exhaust manifold and adaptor to hold on the turbocharger contributes greatly to the reliability of the conversion. The compression ratio has been left standard at 9:1 and the Microdynamics turbo control system prevents any damage to the pistons via means of retarding the ignition when the engine shows signs of developing knock phenomenon (although this has now been changed in favour of a special Pace distributor). This sophisticated package works unobtrusively, but it's function is vital to prevent major damage to the engine.
The Lumo 105T conversion on the Fiesta XR2 works well and looks very neat. And when you look at the performance figures you can see that it has certainly blown some new life into the old cross-flow Ford. GS
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Middle - Option on UBM car are these 15" wheels with P7 rubber
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