Crews who move on to road rallies from Scenic Tours usually start with novice level UK events and the advice on car preparation in Scenic Tours is equally applicable to novice level road rallies. Initially, reliability is more important than car performance as “To finish first, first you have to finish” and crew performance is likely to be the determining factor.
But before embarking on any modifications to the car, it is important to know what is and is not allowed within the Motorsport UK/HRCR regulations. Apart from safety equipment, which is defined in the ‘Blue Book’, a wise starting point is to purchase a set of Homologation Papers for your car from the Motorsport UK. These show what modifications were homologated in period and are therefore allowed today. Anything else can be a matter for discussion with the Eligibility Scrutineer and that is best carried out before arriving at an event. Reading through the web site at hrct.co.uk is also highly recommended. Whilst the regulations can at times seem very restrictive, the aim is always to provide a level playing field for everyone, keep costs at an affordable level and keep the cars as they were rallied in period.
The role of the navigator is critical for success at any level and for a navigator to do their job a good working environment is necessary. This may mean fitting competition fixed-back seats and a full harness, but if you do start out using the original seats then the backs must be secured so that they no longer tilt forward. The navigator will probably require a foot rest so that they can brace themselves when using a map board and, if night events are being planned, a power supply for an illuminated magnifying Poti and an additional light that enables Ordnance Survey map colours to be seen correctly. In addition to a tripmeter that does not display speed or average speed, clocks and timers will be required and the normal set up is two for the navigator and one for the driver. Digital stopwatches are allowed on most events and all sorts of types are in use from cheap kitchen timers to expensive rally timers designed for road rallies. There is a large amount of paper involved in rallying and additional storage for maps, speed tables, road books, time cards, pens and pencils will be required but these are best manufactured and fitted as you develop the car with the navigator.
Under body protection
Some rallies use rough, or very rough, roads and additional under body protection becomes essential. Often the most vulnerable item is the exhaust system and where there is no option to fit it closer to the body or re-route it, simple welded skid plates on the leading edge of silencer boxes can provide a lot of protection. The replacement of bolted joints with ones held together with springs helps to prevent damage if the worst should happen and the system falls off, with the springs allowing easy reassembly. Do not modify the exhaust in any way that will reduce its silencing efficiency, as a lot of classic exhaust systems only just make the Motorsport UK noise limits in their original form.
Fuel tanks and engine sumps are also vulnerable to attack by hidden rocks but can be protected by the addition of alloy sheet guards bolted to the body. Unfortunately, the fitting of an engine sump guard can also require the fitting of an oil cooler due to shielding of cooling air over the sump by the guard.
As you become more experienced and move up to more demanding rallies then it may be desirable to fit a roll cage. This is best left to professional installation but the fitting requirements are detailed in the Blue Book. At the same time additional protection for brake and fuel lines may be advisable and these can be run inside the passenger compartment although UK Historic regulations require the retention of significant portions of interior trim including the rear seat.
Moving the fuel tank to the boot for added protection is a common modification on some cars but will require the bulkhead between the boot and passenger compartment to be made fire proof.
A dynamo based electrical system may be changed to an alternator based one and, if the electrical system is completely original, it should be overhauled, paying particular attention to fuse boxes which deteriorate over time, and earth bonding which tends to suffer from corrosion build up and can produce some very strange faults. Consideration should be given to relay switching of the larger electrical loads such as headlights along with additional fuses so that if one light fails it does not effect anything else. Electrical modifications of this type are best implemented by an additional wiring loom rather than attempting to adapt the existing one. Depending on the level of rally entered, a FIA cut-off switch which disconnects the battery and stops the engine may be required, but they are a sound investment from a safety aspect no matter what the level of event.
Do not ignore the serviceability of standard equipment such as windscreen wipers and washers. It does rain on competitive sections and you will need good visibility. Likewise, a working heater to demist and keep the navigator happy is a serious requirement.
Suspension and brakes
Tyre sizes and wheel widths are also controlled and the fitting of extra wide wheels of greater than 6’’ width is prohibited but in reality are not required anyway. Changes to suspension components, including shock absorbers and brakes, are also very tightly controlled and little change from the original specification is allowed.
Likewise, brakes cannot be modified from the original specification, except for pad and lining material and changing from single circuit to dual circuit hydraulics, so it is vital that all brake components are in good condition and working properly. That includes the handbrake which will be needed on tests for handbrake turns.
Allowable engine modifications are limited to those that have been homologated and for UK night rallies, cars with more than two choke carburettors are prohibited on the grounds of noise.