I started to build an app for my BlackBerry 10 device to help me remember all of the modifications done to the car. I “might” also add an Arduino board to the car and control some of the systems that way via Bluetooth 🙂
Pics of new Engine Configuration
Here are some more engine bay shots. I’ll get some good quality shots in the spring when I get everything all polished. Â The car is tucked away for the winter right now.
By moving to the speed density tuning, I should also likely be able to get of the intake pipe and run a filter right off the turbo compressor housing.
Tuning with Speed Density
My old EcuTek, 20G and the 73mm big MAF worked fine before.. however with the bigger turbo it’s exceeding the limits. For reference, my car has an 02 ECU with EcuTek.
From my understanding this is how I believe things work, and why it’s now exceeding the limits.
Basically the MAF sensor and ECU combo have a maximum reading of how much air is being sucked into the car. Lets just say for argument sake that’s 300 grams. What happens when you run a larger turbo than stock, under boost it can start to pull much more air in faster than expected which “can” exceed the max 300 grams measured. To give you an idea, my car with the new turbo at 16psi of boost was at 280 of the maximum 300 grams that could be metered (NOTE: numbers are just a hypothetical example).
So what was happening with the car, is that it really didn’t know what to do with all the extra air coming in, the ECU/Sensor hits its limits, and the car bogs with power dropping off the table.
A trick that is used to try and get around this issue is to use a Big MAF. This increases the diameter of the tubing where the sensor goes, which in turn slows down the speed of the air going past the sensor. You then can make adjustments to your fueling under boost based on your tuning for the extra air while having the ECU still believe it is within the maximum limits.
Some people have gone as far as up to a 100mm Big MAF when using large turbos. The bigger the turbo the more amount of air consumed at a higher velocity past the sensor, thus reaching the limits quicker.
However, there’s a downfall to the Big MAF route. Which is around trying to get the car to idle. Tricking the system at boost works great, but now you have VERY slow moving air past the sensor at idle, and trying to get a car to idele with 800cc injectors with what the ECU/Sensor thinks is low amounts of air coming in is really tricky.
Now the tricky part is that if you go with a standalone unit like the Vipec, you have emissions issues here in Ontario where the factory ECU needs to be retained. Luckily Cobb has now released Speed Density tuning with its Access Port. I’ll likely be going that route in the spring.
Back From the Shop
Brought the car back from the shop today. I’ll need to move to a vipec system in the spring. Basically the power is dropping off at around 4500-5000 rpm.
Once she starts making some power there’s too much air being pulled through the MAF and it can’t keep up with metering the air. Even at 16psi it was pulling nearly 80%+ capacity of the upper limit of the MAF. Even with my big MAF and EcuTek. I’m now running the Ultimate Racing T3/T04E, which is basically a journal bearing GT30.
The car does feel great, and you can start to feel it build some power, but then it just drops off. We’ll give it a go again for tuning in the spring. The car is now put away for the winter. I don’t have any pictures of the new setup because it was all dark out tonight with poor lighting. Frank has a few that I’ll try and get from him and post up.
I’m happy with the look of the engine bay though.. lots of polishing to do in the spring, a new tune and we’ll be all done with the car.
The TMBLER 