Rolling Road Diagnostics
The Rolling Road allows us to tune the engine under varied loads and speeds. Whenever you modify your engine it is good idea to check its performance on the rolling road, as this can prove a performance increase or highlight any issues that may have arisen.
Sometimes an engine modification or a problem will only affect performance in a certain part of the rev range, and a rolling road is the ideal tool for diagnosing this - as you are able to hold consistent load/revs for much longer than is practical on the road in order to test different solutions, or tweak for little bit of extra power! It can also provide a power/torque plotted graph to give an overall indication.
How do we use the rolling road
Cars with around 100bhp at the wheels are usually easy to tune. When we get motors with greater BHP we have to be careful not to overheat, tyres, and underbody. To cope with the heat produced we use a large 3-phase cooling fan blowing air into the radiator and under the car, as well as an extractor fan behind the car to pull exhaust gases away and out of the building. These more powerful cars have to be strapped down to prevent them from driving out of the rollers.
We use certain meters to help us tune the car. We attach an oscilloscope to the engine electrics to check voltage ranges,
and a lambda sensor in the exhaust with a display that can be read from the driver's seat. This allows us to measure the oxygen levels in the exhausts gases, and we aim to keep these at an optimal level.
On engines with aftermarket engine management systems (such as MBE, Omex, DTA, etc) we can adjust fuelling and ignition timing electronically to optimal levels to increase BHP and improve economy. On engines with Carburettors we have to adjust the fuel by changing jets, emulsion tubes, air correctors, etc on Weber-style carbs, or needles, jets, etc on S.U Carbs. The ignition timing can usually be adjusted by altering the position of the distributor advance curve.
Rolling road checklist
Before visiting us there's some simple checks to make the job much easier (and much cheaper!) if you check your car over prior to your rolling road run. Things like oil, water, cambelt condition, etc - essentially make sure your vehicle is in good shape before you arrive. Alternatively, you can book your car in for a full or interim service, which we'll carry out before your rolling road session.