How to Setup and Use Virtual Dyno for your VW GTI

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The Cobb AccessPort unleashes a continuous bombardment of information. The screen can be setup to display 6 live engine statistics with each showing min/max figures. This is just the surface; with the touch of a button, it’ll begin recording a variety of parameters of your choosing. That’s a lot of information that was previously inaccessible. What does this mean? What’s will this information tell me? I’m glad you asked!VW_GTI_Dyno

One of the more fun things to do with all this data is to plot your own dyno curves based on full gear pulls! Do you know when your optimal shift points are? Is it worthwhile revving the engine deep into redline? Where could I gain time? When does my turbo really spool? What’s my baseline power? How much power was gained from the last mod or tune? Once you see the power curve, these questions are easily answered!

So let’s talk about V-Dyno. Just like an in-ground dynamometer it measures the force (torque) applied by the engine to accelerate your car. Let’s say you go out driving, it’s the middle of boost season, and the car is running like the prized thoroughbred it was built to be. Everything feels good, ear to ear smile, but then, what do you tell your buddies? My butt-dyno says I make 347WHP? They’ll laugh you out of the stable. Instead take a data log. Let V-Dyno crunch the numbers, and have a printout that your car is actually making 347WHP! If the datalogs you take are consistent (as described later in the article) and you setup your car’s parameters correctly, Vdyno can be very accurate and repeatable and we have correlated our results to in-ground dyno data.VW_GTI_V_Dyno.JPG

So how does it all work?

V-dyno analyses engine speed (RPM) and calculates acceleration performance based on the rate of change of engine speed in a single gear. It factors in tire size, weight of the car, gear ratio, ambient air temperature and frontal area of your car and a number of other things such as occupant weight. You’ve probably heard “oh but that was power on such and such dyno so the numbers are skewed this and that way”. Well, that’s also built in. You can select your dyno type and correction factor. There’s a large amount of preset cars in their database but we’ve build a good profile for the VW GTI. You can build the same profile in your own installation of Vdyno using the information below.GTI_DSG_V_DynoGTI_6MT_V_Dyno

How do I collect data?

First, the AP has to be setup to record all the useful parameters. For Vdyno you need to log at least AFR, Accelerator Pedal Position, Boost Pressure, and RPM. You can log others as well, but these are the ones that are used in the calculation. Then, while driving make sure you are in the Gauges screen. The car will need to be cruising in 3rd or 4th gear, around 2500 rpm. Click the center button to start recording. Wait a second until the screen on the AP starts refreshing again, and then stomp on the gas as if it were an on/off switch. Take it to redline, release the gas pedal, shift up, then click the center button again to stop recording. VW_GTI_Dyno_Sweep

Your final results are only as good as the collected data. Here are a few hints to getting repeatable V-dyno results:

  • Make sure it’s not windy
  • Keep ambient temperatures consistent
  • Always collect data on the same stretch of road
  • Empty your trunk
  • Don’t take passengers along
  • Gas tank half full
  • Do 2 or 3 passes
  • 4th gear logs are better than 3rd
  • Stay safe!!!

I have logs, now what?

Transfer them to your computer using the AccessPort manager. Download Virtual Dyno, and set it up with the correct profile for your car. Match the columns up. Then drag and drop the logs in, wait a second and you’ll see your power curve.

But my power curve looks strange.

There are a number of things that will skew the data and so the end result will be way off. If you see strange humps, bumps, and non smooth curves, chances are that the car lost traction, you had clutch slip, there was a big bump in the road or something else went wrong. If you come up with something odd and want to chat about your setup (and how to get more power) drop us a line!

Happy Vdyno-ing!

Stratified Fiesta ST Tune Progress and E85

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Just a little recap on our Fiesta ST. We have tuned it on 91 octane with a COBB intake and no other engine performance modifications. It made very nice power and the little car is just tonnes of fun to drive! Now it was time to see what E85 will do and that meant strapping it on the dyno. Fiesta ST E85 Tune Dyno 3 (Medium)

A little run-down on E85. E85 has a high resistance to knock (high octane) and we love this about it because it allows us to push both boost and timing higher without reaching the dreaded knock threshold and thus make more power with no other hardware changes other than an E85 specific tune. The Fiesta ST uses a high pressure fuel system since it is direct injected and while E85 adds octane, it also takes away fuelling headroom. We were able to watch knock response as well as all fuel pressures using the COBB Accessport.Fiesta ST E85 Tune Dyno 5

To run full E85 the fuel system would need to flow 30% more fuel and the high pressure fuel pump would have a hard time keeping up. Because of this we chose to run an E85 blend. That means we mixed 3 gallons of E85 and topped off with 91 octane. The effective mix is around E30 and it adds enough octane such that we can reach MBT (meant best torque) on the stock turbo. What that means is that we were able to advance timing until no additional power was being made and the engine remained knock free.

So this trip to the dyno served several purposes. First, it allowed us to search for and find MBT on the Ecoboost 1.6l in the Fiesta ST. Secondly, it helped verify that the E30 mix offered enough octane to reach MBT on the stock turbo while not depleting the OEM high pressure or low pressure fuel pumps. Finally, it allowed us to build our Stratified E85 Flash Tunes and also verify that by switching to an E30 blend and tune, you will gain approximately 15whp and 15wtq with no other hardware changes. Stratified Tuned Fiesta ST E85 Dyno

On such a light car, those power gains can definitely be felt and add to the enjoyment of an already fun car!

Tuning the MK6 GTI: Stg 1, E85, Limits and Findings

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We have been tuning the MK6 GTI using the COBB AccessPort and working with a bone stock vehicle to start. It is a 2011 3 door DSG model. The car is very pleasant to drive and the first step to improving the experience is to add power safely and improve driveability.Stratified AccessPort COBB Mk6 GTI Tune

With a bone stock car (what is known as Stage 1) which just includes a reflash of the ECU you can get the majority of the power that the stock turbocharger can offer from just the tune. We started by ramping up performance from stock by adjusting boost, timing, and watching all vital engine parameters such as knock, air fuel ratios, charge air, and engine temperatures. A lot of seat time and stress testing of the calibration backs up its resilience. The car drives as stock until pushed and when it is pushed it delivers a smooth rush of torque that doesn’t fall flat in the upper RPMs.

On 91 octane fuel we were able to add a peak of 32whp and 69 ft-lb of torque over stock and 24whp and 48 ft-lb of torque over the COBB OTS tunes. The overall area under the curve gained however is what makes the car very enjoyable to drive.Stock VS COBB Vs Stratified Stg1

The torque ramp from low in the RPM range makes the car quite eager to accelerate and makes passing a breeze. The engine is not very knock prone which is great to see and even on 91 octane fuel we were able to achieve very consistent results.

Before adding any bolt-ons we decided to increase the fuel octane and search for what we can achieve with an E85 blend. Often an E85 blend and tune will net a very nice power increase. With the COBB AP it is also a breeze to switch between different fuel blends and tunes within minutes.

On most direct injection cars, blending some E85 with premium pump gas fuel allows you to tune very close to MBT (mean best torque) and maximize both boost and timing (especially on a stock turbo). For this, we strapped the GTI down on the dyno and mixed 4 gallons of E85 with E10 91 pump gas fuel.Stratified Mk6 GTI Tune

This achieved an E30 fuel blend. On this blend approximately 10% extra fuel volume must be delivered and both the high pressure fuel pump, low pressure fuel pump, and injectors are up to the task of delivering the needed fuel on the OEM turbo.

With the E30 blend we were able to achieve an additional 15whp and 26wtq on the bone stock car.

VW GTI E85 Stg1 vs 91 Stg 1

Boost was maintained at similar levels but we were able to push timing to mean best torque (MBT) meaning that we were able to add timing until we did not gain any further performance while remaining knock free.

At these power levels we are actually leaving some torque on the table between 2700 and 4000 RPM and this is why boost levels remained similar. This is because we have reached the programmed torque limit for the DSG transmission in our test car. This torque limit is set to 350nm and you can see that we are riding this limit in the graph below. The turbo is able to supply more boost and in order to achieve higher torque values in the lower RPMs, a DSG reflash is needed (and coming shortly). The DSG hardware is able to handle the extra torque; we just need to program it as such!

Torque Limit Reached VW GTI DSG

Even without a DSG flash, the car has a lot of potential with just an ECU tune. Adding flow parts will give us some top end performance and we will see an even flatter torque curve. As we continue to develop for the GTI and have applied our years of direct injection tuning expertise, we are now offering pump gas as well as E85 tunes for the MK6 GTI which can either be packaged with a COBB Accessport or bought individually. We are also going to continue updating you on our development and tuning progress. If you have any questions, don’t hesitate to Contact Us!

Making your Fiesta ST Handle Even Better

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The Fiesta ST (FiST) is an excellent handling car. Not very often do you have front wheel drive (FWD) cars handle as well as the Focus and Fiesta STs. There are several things that make the Fiesta stand out in spite of it having quite a conventional and simple suspension layout (with a solid rear axle!).Fiesta ST Stratified AutoX

One of the advantages the FiST has over the competition is its light weight. There is little that can make as much of a difference as shedding weight. The reason for this is that changes in direction (changes in momentum) require a lot less energy. This in turn translates in less energy lost between the tire contact patch and pavement, less energy lost in compressing the suspension, flexing the chassis, etc. The second great thing about the FiST is the way the suspension was setup from the factory. It is a stiff suspension for a production car; but this is what us enthusiasts crave. Finally, let’s not discount Ford’s torque vectoring. This little trick allows the chassis ECU to independently apply the brakes to any wheel in order to make the car rotate and apply power more effectively in corners. This is something used in the Focus ST and RS as well. All of this adds up to a car that is very happy to handle the turns and that means fast lap times!

Is there a way to improve on this already great recipe? With some careful planning there is! What you want to avoid is to take away some of the rotation happy characteristics of the car. That means that I recommend leaving the sway bars alone initially; especially on a car this light. Instead focus on grip (tires, alignment) damping (shocks) spring rate (springs), and brakes.

Coming to the shocks and springs discussion; I always recommend upgrading to something with the best shocks. Springs are simple compared to the shocks and the ride quality as well as handling bumps and corners almost always comes down to the shocks. A personal favourite is Bilstein for me. They have a reputation for making great shocks and whether you get a B8 shock + spring combo or one of their coilovers you’re in for a treat both on the street and track. We recently installed a set of B14 Coilovers on our 2015 Fiesta ST and they have been great. We have these same coilovers on our 2014 Focus ST as well. Very affordable combined with great performance makes the B14 a go-to option when upgrading the suspension. From our experience – here are a few install tips for the Fiesta ST:Fiesta ST Bilstein Front Built Stratified

  • Purchase the top hats (PN C1BZ3A197D), front strut bearings (PN 8V5Z18198A), and dust boots (PN 8V5Z18A047A) (these act as a spring insulator as well) from the dealer before embarking on the job. You will need two of each. They are affordable, make the assembly of the front suspension a breeze without needing a spring compressor, and they are wear items that should be replaced when upgrading the suspension. Fiesta ST suspension
  • When installing the front suspension, push the front strut assembly at the strut tower towards the inside of the car before tightening it down. This will give you the most camber you can get without camber plates. Camber is a good thing.Fiesta ST Bilstein Front Stratified
  • When installing the rear shocks, before bolting them to the chassis apply some grease to the top of the bushing (you will reuse the OEM one) and clean the chassis and mounts. If you don’t do this you will hear squeaking from the rear suspension when driving.
  • When setting up the ride height, allow the car to have a bit of rake and don’t “slam” it for best performance. You want to look at the front control arms and allow them to be relatively flat with the pavement. Fiesta ST Bilstein Installed Stratified
  • Get a professional alignment to set the front toe, make sure the steering wheel is straight so you won’t get poor tire wear. Fiesta ST Bilstein Stratified Alignment

After this get out there and enjoy the car. The ride will be a little stiffer but should feel compliant and not jarring. You will notice less brake dive and less body roll. The car should have very good turn in and still be very very happy to rotate. We’ve taken the car to autocross with just this suspension change (and our COBB AP and Tune) and it proved to be one of the fastest cars there … even putting a few expensive German sports car to shame.Fiesta ST Bilstein Installed Stratified Autocorss

It should be mentioned that this Fiesta has a few other modifications installed and these give it more pull out of corners with excellent throttle modulation and control and a nice induction sound.

For tires, there are lots to choose from out there. Because the car is so light you can get away with tires that are a little less extreme than what most use for the same application. The tire wear will also be good, again, because of the light weight. The OEM tires are good and you can work your way up from there. Even for an open track day you can do very well with a set of extreme summer tires such as the Bridgestone RE11/RE71, Dunlop Direzza and others in that category. Those tires would also be great for auto-x as they come up to temperature relatively quickly.

To improve handling further on our particular car, we are looking at tires and brakes next. Engine performance wise, the next steps would be an upgraded intercooler and/or WMI, and some exhaust work. These should maximize the power potential (and sound) of the stock turbo before thinking about upping its size just a bit … Stay Tuned!

Upgrading your Ecoboost Fuel System – Part 1 – How it Works

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As the power levels rise for the Ecoboost powered cars, there is a need for additional fuelling over what the OEM system provides. Choosing the correct fuel solution for your needs is important so this 3 part series of articles will walk through how the OEM system works, when you need to upgrade, and finally, what the correct upgrade is for you.

So let’s start with the basics and look at how the OEM Ecoboost fuel system works. As you know, the car uses a direct injection fuel system that pressurizes fuel to above 2000psi (we can and do target higher pressures but as soon as flow drops so does pressure – more on this later) before injecting it directly into the combustion chamber. The fuel system is made up of the following components:

An in-tank returnless transfer pump (LPFP). This pump is electronically controlled via the tune and it can operate at pressures of up to 100psi. On the Focus ST, this in-tank pump can flow up to around 475whp worth of fuel. From all the OEM fuel system components this is the highest flowing component and the last to run out or need an upgrade. It sits inside the tank in an assembly that looks like this:Focus ST Ecoboost Fuel Pump In TankMoving from the tank there are 5/16 fuel lines that travel under the vehicle and up towards the rear of the engine bay. As the lines enter the engine bay there is a low pressure fuel sensor that you can monitor via the COBB Accessport or similar device. This sensor is what the ECU uses to target the desired LPFP fuel pressure and you can use to see the health of your LPFP

This feed line is then connected to the inlet of the HPFP (high pressure fuel pump). This pump is driven by the exhaust camshaft of the engine. In the 1.6 and 2.0 EB engines the camshaft has 3 lobes. On the 2.3 (Mustang EB, Focus RS) it has 4. So for every single revolution of the camshaft (every two revolutions of the engine) the pump is actuated 3 (or 4 for the 2.3l) times.Focus ST Ecoboost High Pressure Fuel Pump 0

The pressure is controlled electronically via a solenoid inside the pump and via the ECU/tune. But keep in mind that the pressure is also related to the amount of fuel FLOW the pump can deliver. And this is a function of how quickly the pump piston is move up and down, the amount of fuel moved during a single stroke of the piston, and the inlet fuel pressure of the pump. On the EB motors, the HPFP is the first to run out of fuel flow, especially at low engine speeds (because the camshaft is also moving slowly)Focus ST Ecoboost High Pressure Fuel Pump 1Below is more on the fuel pump operation for those interested. Focus ST Ecoboost High Pressure Fuel Pump 2Focus ST Ecoboost High Pressure Fuel Pump 3The high pressure fuel is then delivered to the high pressure fuel injectors and the fuel pressure is measured by a sensor on the fuel rail. These injectors sit on the intake side of the engine. They are the second part that will run out of flow on the various Ecoboost engines. However, they do so AFTER the HPFP and this is a key thing to remember. Without upgrading the HPFP, higher flowing injectors won’t be of help by themselves. Ecoboost Fuel Injectors

So to recap, the OEM fuel system consists of an LPFP in the tank (good for 475whp on the 2.0l), an HPFP driven by the exhaust cam (good for 380 ft lbs of torque and 370whp on the 2.0l) and a set of injectors (good for 380-390whp on the 2.0l). The 1.6l runs out of fuel around 50whp earlier and 2.3 has around 30-40whp extra in hand. Part 2 of the article in the series will go over how to tell if your fuel system is in need of an upgrade and some of the issues that come with direct injection fuelled engines. Part 3 will go over the solutions and how to stay safely fuelled. Stay tuned!