This week we had the pleasure of inviting the Oxford Universities Motorsport Foundation (OUMF) to test and tune their racing Riley 1.5 on the rolling road. Ding Boston and his crew of students were here bright and early Saturday morning with the car and a selection components they wanted to test.
First, we established a baseline. We made sure the fuelling was adequate and did a power run. This data was saved on the computer so we could compare the torque and power curves as we worked through the day. Baseline power peaked at 155.3bhp. Next, we advanced the ignition timing to see how the engine reacted. Power dropped to 151.2bhp so we set the timing back to where it was.
Next, we tried a new inlet manifold and short trumpets on the Weber DCOE carburettor. This time the power jumped up to 160.2bhp. Great result. Torque was down to 141.7lbft so we tried some long trumpets. Power was virtually the same at 160bhp dead but the torque came up to 143.7. Lastly we ran the car on an open exhaust. We adjusted the jetting in the Weber carburettor to compensate and it made the best power of the day at 162.2bhp and 144.7lbft of torque.
A day well spent and a Riley 1.5 rolling road tuned to peak performance.