SBD OMS25 – 2.0L Duratec
The car went to BTB Exhausts to have it’s new exhaust system designed and manufactured to fit neatly inside the side pod. The exhaust system was on display at Autosport International on BTB Exhaust stand in Engineering.
We built and ran a new 2.0L Duratec engine just before Christmas for which we had designed a new exhaust manifold which has helped to produce a few more horsepower and a stronger spread of torque, just under 310bhp, 200lbft torque.
Unfortunately due to our workload, we ran out of testing time and believe that with a few adjustments to the exhaust manifold and minor tweaks to the engine another 5bhp should be easily achievable.
We then got to work adding all the electronics and hardware that we would be testing and developing throughout 2013, ready for sale for the following season. We took the already proven MBE9A9 ECU that we have used on Mark Smith’s Reynard and Trevor Willis’ British Hillclimb Championship winning car and started to add even more features, the most interesting of which is fly-by-wire. Although MBE have been using fly-by-wire (or EGAS) for many years in their production and pre-production ECUs, we now felt it was the right time to develop this for the aftermarket. We have spent the past year with Jenvey Dynamics fine-tuning their prototype motor unit, which will be ready as production items for the beginning of this season.
In motorsport we use fly-by-wire for different reasons to why they are used on road cars. Production car ECUs use fly-by-wire to take some of the control away from the driver, usually slowing the throttle down to control emissions whereas in motorsport we are looking to achieve the fastest throttle response and peak torque at any point in the rpm range. With fly-by-wire we can limit the amount of throttle opening if this produces better peak power than full throttle, we can slow the throttle down if this produces better throttle response, thereby making an engine that is normally not the nicest to drive into a more driveable engine.
As the year goes on we will integrate the software into our launch and traction control system, which will allow the user to control the amount of power required during starts to achieve optimal starts and reduce the loads on the transmission, which as we all know can be very expensive when they break. Steve Owen has also made me some special wings for the sprints, since the downforce he was achieving with his latest wing designs were becoming so high that even Trevor Willis commented that he had more than enough and was occasionally backing his wings off. The wings that Steve has produced for our use have reduced downforce, which is more suitable for the sprints.
We collected the new OMS25 from Steve Owen in October 2012. Although Steve Owen had finished the tub the previous year, Steve B wanted to mount the 2.0L Duratec engine to it, so because this was a completely different engine to anything he had mounted previously, everything had to be designed from scratch. He designed and machined a cam cover from solid aluminium taking many hundreds of hours, but once this was completed, it allowed it to be bolted directly to the tub and then via a frame to the gearbox.
Then once our dry sump system was also linked to the tub and bellhousing, this significantly reduced the stress on the engine, which meant we didn’t need to fit the side frames, which helped to reduce the weight significantly and greater access to the engine itself. As you can see from the photograph, Steve (OMS) has put in a huge number of hours in the design and construction of the back end of the car to accept our Duratec engine.