Working on developing a series of intake parts for the 2.0t cars. Some have been done by others already, some haven't. I can't see myself paying over $300 for just an intake tube.
My first plan of attack is to adapt a bigger throttle body to the 2.0 intake. The 2.0 has an itty bitty 59mm throttle body. But the intake manifold has a 67mm opening.
The most logical thing to do was to adapt a 72mm v6 throttle body. Which I did today and conducted a flow test. I have not attempted to run it on the car yet because I need to source necessary couplers.
Here's a shot of the stock 2.0 throttle body next to a stock unmodified v6 tb
Because the inlet hole on the intake manifold is already almost 10mm bigger, this leads me to believe the throttle body may be a restriction. Thus far, I believe I am correct. I CNC machined a throttle body adapter with a tapered inlet. The front matches the 72mm throttle body, while the rear tapers down to 67mm to match the opening on the intake manifold.
Throttle body adapter, with oring groove for throttle body seal.
Adapter mounted to intake manifold.
I did the flow testing in house on my Super Flow flow bench. For the sake of trying to test bottle necking as much as possible I also did the flow test through the tube that attaches to the throttle body that comes back from the intercooler. Basically I tried bottle necking it down again before the TB because that tube is pretty small also. I plan on attempting to rebuild that tube in a larger size to flow more air also. Shown below is that tube taped to the larger throttle body, adapted to the stock intake manifold. I expect even better results adapting that tube with a proper silicone coupler, as it was just tapped it appeared slightly off center and it obviously wasn't optimal, but it was a good first test.
So tested stock tb through the tube, vs the bigger TB through the stock intake and stock intake tube... Just by changing the throttle body I saw a 6.5% air flow increase through all that, which is HUGE, for just changing a throttle body on something like this.
That's said, I am excited to actually try this on the car and hopeful that it will work. The silicone coupler I need is on order and I should hopefully be able to try this in the car next week if I'm lucky.
The other parts that will be rehashed in the aptly dubbed "Big Mouth" series of parts a make will be the tube that connects directly to the TB seen in the previous picture, and the tube that runs from the airbox to the turbo. It looks like a big restriction.
I'm sure you'll all start screaming "why don't you build a cold air intake?!"... Well at this point, I'm not sure that the 2.0 actually needs one. So far in my data logging completely stock, at speed, I'm seeing 2-4 degrees above ambient temps as read at the IAT sensor. I think getting rid of restrictions such as the things that I am working on, and perhaps a high flow drop in filter may just make a world of difference.
Btw, here is the intake tube from the air box to the turbo disassembled
The white thing seems to be a noise suppressor. Seems like some of the ATS guys have been pulling it out. I've read it gives a little more intake and turbo noise. People claim the car runs harder, but I don't see how, it would create a huge amount of turbulence in the intake tube if it was removed. I have debated building a solid insert to replace the white one, but I think the gains would be minimal at best. Might be good for California guys looking to fly under the radar.
Everything I do here will be Dyno tested adding one piece at a time. I'm hoping I can maintain the stock tune while doing all of this and hopefully show some nice gains. Eventually when I have to, I will start messing with tuning. But I'm hoping I can maintain the stock tune at least until I crack open the turbo.
Stay tuned!