[TECH TOUR] As you’ve possibly seen on our social media pages we tuned this Ford Focus hill climb car for the 2017 'Pikes Peak International Hill Climb' earlier in the year. Since this is something we don’t get to go over everyday we thought it would be nice you give everyone interested a little bit of a technical tour of the car.
In this article: Now and Then | Powerplant & Gearbox | Weight distribution | Electronics | Brakes and Tyres | Aerodynamics | Tuning for Altitude | Sensors | Suspension | Fuel and Cooling | Lubrication
Owned by Tony Quinn from Australia this car is based very loosely on a Ford Focus. It was built by PACE Innovations in Queensland in Australia who are also responsible for the V8 Supercar ‘Car of the Future’ chassis.
This car was built initially from the ground up to compete at the now unfortunately defunct 'Race to the Sky' event in the Cadrona Valley here in Queenstown, New Zealand. This was a gravel hill climb which required a few specific components that have now been changed a little to better suit tarmac surfaces.
One such change are the rims. The car was originally built to compete on 15 inch wheels which at the time gave the opportunity to run the well proven World Rally Championship tire options.
As Pikes Peak hill climb has no gravel sections at all these days 18 inch rims have now been fitted instead in order to give increased tarmac tire options as well as allowing for bigger brake rotors in the future if required.
As you can see it also sits pretty low on our Mainline dyno which was done to increase handling and aerodynamic performance and could again be done due to the switch from gravel.
It’s called a Ford Focus, but honestly there's not really a lot of Ford Focus left with just the A and B pillars being original components. Another project that PACE Innovations worked on previously was a Ford Focus-based endurance car and as such they already had a lot of experience producing these panels which was one of the reasons for this choice of direction.
There’s a bit of a surprise here, much to the disgrace of Ford fanatics, in the form of a VR38 V6 twin turbo engine from a Nissan R35 GT-R. Initially there was a little bit of debate about using a Ford Coyote V8 however packaging was too much of a problem for this setup to be viable.
Anyone who's watched what's happening in the world of drag racing with R35 GT-R's will be well aware that it doesn't take a huge amount of modification to make power from a VR38 and as such this is a fairly basic build that has slightly larger Garrett turbochargers and Turbosmart external wastegates.
The engine is rear mounted but upon close inspection you may notice that it's offset and on a slight angle towards the left hand side of the engine bay. This is a packaging problem due to the fact the car doesn't run a conventional R35 gearbox straight off the engine but rather has a prop shaft going forward to a motorsport orientated Holinger six-speed sequential dog-engagement transaxle that is front mounted. Gear changes are done via an air-shifted paddle arrangement which we will cover in some more detail soon.
With the engine rear mounted and the gearbox in the front, the overall weight of the car is very evenly split. The aim was to get as close to 50/50 as possible and they ended up with a 53/47% split when taking into account an 80 kg driver and 15 kg's of fuel for a run, so it ended up very close to this goal in final trim.
So while the weight distribution is an advantage of the packaging setup, one of the disadvantages is that the rear diff has to be offset slightly to the right hand side of the car to give room for the rear driveshaft to run through. Located on the the main prop shaft coming out of the bellhousing of the rear diff is the drive for the alternator. As you can imagine mounting an alternator in such a tight setup like this can be quite a problem and originally the alternator was actually driven off the right rear axle, however this didn't prove to work that well and the change means the electronic system will now be charging any time the engine is running.
The electronics package that is powering the car includes a MoTeC M150 ECU with the GPRP (general purpose race paddle) package and a MoTeC C125 dash unit. The paddle shift system is air actuated via the shift tick paddle system on the back of the steering wheel. To shift down, we simply use the left hand paddle and to shift up, we use the right hand paddles and other than starting and stopping operation is clutchless. Because of how tight the cockpit is, not needing to use clutch all the time really makes operation a lot easier for the driver.
The gear shifting is all controlled via the MoTeC M150 ECU. When the driver requests an upshift the ECU will momentarily cut the engine power by using an ignition cut which allows the drive dogs and gearbox to disengage and the next gear to be selected. The gear cut is only as short or as long as it needs to be in order for the next gear to be selected, and that can be as little as about 40-60 milliseconds. It’s both faster and more consistent than the driver could even achieve shifting by hand.
Things are a bit trickier for a downshift as we would normally need to ‘blip’ the throttle while clutching in to match revs with the next gear down. Now remembering that there's no clutch required for an upshift or a downshift with this setup what happens is that the ECU will do this for us when a downshift is requested by activating the factory VR38 drive-by-wire throttle bodies
This really is quite an advanced system as the ECU knows the gear ratios of the gearbox, is constantly checking the gear position, can calculate what the engine speed will be in the lower gear and then blip the throttle to exactly match the engine RPM. It also has the ability to retry a shift so if for any reason the driver selects a gear and the finds it doesn't engage properly, then the ECU will detect the error and try to shift again. It can do this multiple times and is known as a closed loop control system.
All of this makes the whole gear change process relatively seamless and incredibly smooth. It also allows the driver to concentrate solely on the task of driving the car as they can keep both hands on the steering wheel and because the driver doesn’t need to use the clutch, left foot braking is no longer a heel toe dance between the pedals.
As mentioned earlier the car is now running on 18 inch rims where as it was originally designed by PACE to run on 15 inch. This presented a bit of a problem because in a car that weighs around 1,000 kg's and is able to produce potentially as much as 800 horsepower or more, getting the thing to stop quickly, reliably, and consistently, is obviously difficult, particularly as 15 inch wheels limited the brake rotor size that we can use.
To deal with this PACE used a Brembo carbon rotor and carbon brake pad setup straight from a GP2 car. There's some quite elaborate shielding built around the rotor and the reason for that is that carbon is very easy to shatter, and particularly when it was being used for gravel hill climbs the rotor getting hit by a rock or stone is highly probable and could instantly destroy it. Now that the car's running in a tarmac specification, it’s less of a worry.
Underneath the car there is a little red sensor that monitors the cars brake temperature. Carbon brake packages have the advantage of a high coefficient of friction and still operate exceptionally well at high temperatures, but the flipside is that they are hopeless when they are cold so you need to make sure that the brakes are operating above a minimum temperature range. This sensor allows the team to monitor this situation and if they find the brake temperatures are too cool they can make adjustments, blocking up the right cooling ducts for example, to get the brakes back up to their optimum temperature range.
Last year when the car competed for the first time at Pikes Peak, this team were one of the few teams running in the unlimited class which weren't using tire warmers. While the course is a long hill climb when you're running on slick tires like this it does take some time to get heat into the tire and with the top guys are running the entire hill climb in well under 10 minutes, you really want to be up to temperature and be able to push at maximum pace right from the first corner. So tire warmers are now an essential aspect that I believe the team are looking at incorporating for this season.
A really big focus with PACE for this car was the aerodynamics. This is something that is a little unique for a gravel rally car in which generally down force isn't such a huge design focus and this car is probably more akin to what we see these days in the likes of World Time Attack cars.
Looking from the front with the shell off we can see the air that comes through the front wheel well is vented back out the side skirts, and there is also a carbon tunnel built underneath the from the front that leads to a diffuser at the rear. Although the car also runs a rear wing the idea is to focus on maximizing down force by controlling the airflow underneath the car as well as above.PACE worked in conjunction with another company in Australia to develop this and the results of their computational fluid dynamics (CFD) analysis apparently showed that the car should produce around a thousand kilograms of downforce at 200 km/h.
This magical number means technically the car should be able to drive upside down at that speed, however, I don’t think I’d like to put that to the test personally.
One incredibly important consideration to take into account for Pikes Peak, or any real hill climb where we're seeing a lot of altitude change, is that the tune for the engine is affected by the difference in air density at increased or decreased altitudes. What we mean by that is as the air density drops we have less oxygen available in the air so the car will make less power. Because of this we will need to alter our tune in order to remain consistent with the air/fuel ratio and we may also need to change the ignition timing to keep that optimal.
This is done here with a barometric air pressure sensor, which is wired into the MoTeC ECU, so the ECU can accommodate or account for changes in barometric pressure as the car goes up Pikes Peak. I'm led to believe that the barometric pressure at the start line is somewhere around about 75 kPa. Compare that to standard air pressure at sea level of 101.3 kPa and you're really up against it to start with when trying to make power in these sorts of cars at Pikes Peak.
Luckily what’s in our favor on a turbocharged car is that we can increase the boost pressure as we go up the hill climb, so we're combating some of that lower barometric air pressure by simply increasing the boost pressure. We can't do this indefinitely as there is a limit and we really want to see exactly where we're running in the compressor map, so by monitoring the boost pressure as well as the barometric air pressure we’re able to calculate the pressure ratio that the turbo compressor is working at. By monitoring the turbocharger speed as well, we can see exactly how hard we're driving that turbocharger.
To aid in the barometric air pressure compensations, both turbochargers are fitted with a turbo speed sensor. In terms of other monitoring there is an EGT mounted in the exhaust manifold as well as a wideband Lambda sensor sitting in both turbine outlets which allows us to monitor and control the air/fuel ratio bank to bank via a MoTeC Lambda to CAN module. A nice advantage to this setup is that we can use it for quick tuning on the dyno. By simply pressing a key on the keyboard, the MoTeC ECU will automatically tune the cell that we are sitting in the efficiency table based on the input from those two Lambda sensors. Another use for this Lambda to CAN (LTC) module is closed loop fuel control. Even at wide open throttle this gives the ECU the ability to make small adjustments if necessary to make sure our air/fuel ratio or Lambda number is where we want it to be.
The way the MoTeC LTC module works is that it provides the data over a CAN bus network meaning any other devices that are on that network are able to read from it. This includes the MoTeC dash and while tuning at HPA HQ we have got that information feeding into our mainline dyno as well.
The suspension setup on this car is a little bit different to what you might be used to looking at as the shock absorber has been mounted away from the wheel in order to help with the aerodynamics by keeping the air flowing around the wheel and out the vent as clean as possible. It’s a double wishbone setup with the top wishbones acting as a rocker assembly to actuate the inboard mounted Reiger shock absorbers, which are common on rally cars. There is a shock travel sensor fitted to each shock absorber which allows the suspension damper position to be monitored. This can be data logged through the MoTeC dash for use in tuning the suspension, in particular adjusting the bump and rebound settings inside the damper. Unlike our closed fuel loop, this isn't something that is done in real time by the car but is rather done manually back at the pits after reviewing the data from dash unit.
This car runs on E85 which is a great fuel with a highly effective octane rating, excellent cooling properties and a high latent heat of evaporation, which in a turbocharged car allows us to run a high boost pressure if we need to with the cooling properties also helping the engine run much cooler despite the extra stress.
In terms of cooling, there's a pair of PWR intercoolers mounted nice and high on the rear of the car which under race conditions are fed air via ducts from just behind the doors. These ducts also supply the inlet air down to the turbochargers where there are also intake air temp sensors fitted which tells the ECU what the intake air temperature is doing allowing it to make changes based on the current air intake temperature as required.
The car runs a full dry sump system which is pretty common with just about any high-end race car. Unlike your normal road going engine with a wet sump where the oil is contained in the pan under the engine, this car has it’s oil reservoir in the cabin. At 10 to 12 L it has a much larger capacity than what a normal wet sump would contain which might be 4 to 5 L on average.
Due to it’s long and flat design, when car with a wet sump is cornering at high speed and experiencing high lateral g the oil may be forced away from the pickups which can cause starvation. This is potentially disastrous if the engine loses oil pressure as it doesn't take very long for it to be completely destroyed. A dry sump setup avoids this pitfall as the oil reservoir is tall and narrow and has the return feed for the high pressure oil is at the bottom, so regardless of the cornering forces that the car is experiencing, you're always going to have oil on that pickup. The oil pump scavenges the oil straight out of the engine sump and then it pumps it forward into the dry sump reservoir but because the oil has further to travel, a higher powered and external oil pump must also be fitted to the engine. In this case it’s driven off a tooth belt straight off the front of the ATI damper and it has multiple stages.
Obviously there is also a filter setup in there and an oil temp sensor which is good for monitoring engine health aspects to make sure that the oil is not getting too hot, or conversely, too cold.
Hopefully it has been interesting and given you some insight into aspects of a competition hill climb car that you often don't get to see. The reason we had access to this car is because we were performing some small adjustments to the tune to get it ready to go back to Pikes Peak in 2017. A lot of people would expect this sort of car to be running 1000+ horsepower, but for now that's not really the team's aim so as we’ve seen a fairly mild setup is all that's required.
One of the other aspects we really focused on while we had the car was fine tuning the paddle shift system and particularly trying to smooth out the gear shifts a little, just so the car doesn't get unsettled on an upshift or a downshift.
If you’re interested in learning how to tune something like this yourself, why not take a look at our FREE tuning course?