Rolling Road Checklist, Questions and Answers

Cars presented for rolling road tuning often turn up a few surprises, often for the wrong reasons. Many times we have to repair the car and make it safe before it can even go near the rollers.

If you are bringing your car for tuning it makes sense for you to have a look at a few items beforehand as rolling road time is expensive. A bit of  time and effort before bringing the car in can be very beneficial.

1)  Is the car MOTd and taxed.
Whilst this is obviously a problem for race cars, road cars need to be both MOTd and taxed for the duration of the tuning work. This is because an element of the tuning work is carried out on the open road, and if the car has neither MOT nor tax this cannot be carried out and sadly you would still be liable for the whole tuning payment if the work cannot be finished because of these issues, unless we are made aware of it beforehand.

2) Is the car in a good state of repair?
Rolling road work is generally quite kind on the car .. the runs are done in a controlled environment where all vital signs are monitored closely during each and every run. However we still see cars with basic problems such as perished fuel pipes and coolant hoses, bald tyres or tyres with cuts in the sidewall. A car which is in a bad state of repair cannot be run on the dyno.

Before rolling road work is carried out we do a few basic checks to see if the oil level is good and the oil itself clean, also that there is coolant up to the correct level with no obvious signs of leaks. However we don't have time to do a full analysis of the engine condition and it is the owner's responsibility to make sure their car is in a generally good state of health.
It is because of this that we ask all owners to sign a disclaimer before the car goes near the rollers. This is an industry standard practice at rolling road tuning centres.

3) My car isn't running right and it just needs mapping ..
We hear this one very often and usually the first issues aren't mapping related.
Poorly installed aftermarket ECUs, bad wiring with earth offsets to lambda sensors (very common on ECUs such as megasquirts for some reason) , throttle position sensors which are badly mounted and suffering from spindle play etc. All of these things and more mean we cannot map your car until they are corrected.

4) I brought my car in with plenty of fuel but I was still charged for more ..
Very often fresh fuel has to be added during the latter stages of rolling road mapping. This is because fuel returning to the tank is hot from it's time in the engine bay, and very hot fuel can actually boil in the tank especially if the tank is mounted inside the boot and insulated with carpetting, or the hot exhaust system passes close by. If the tank is not adequately vented extra tank pressure can skew the mixtures slightly on the dyno compared to the open road. Because of these issues it's often required to add fresh cold fuel to the tank to bring these conditions back under control.


And finally a word about bucket seats .. normal bucket seats with relatively low sides present no problems but recently we've had a couple of cars with wrap-around bucket seats which severely restrict entry and exit from the cabin. When a car is on the dyno we need to be able to get into and out of the car easily therefore we politely request that if a bucket seat is fitted which makes entry and exit difficult that it is removed and a normal seat fitted in its place before the car is presented for mapping.