The SteamSpeed STX 71R BB Turbo for FA20 (2015+ WRX) Is Here!

We’ve had customers constantly asking for this for at least a year. This post is going to make a lot of people happy¬†😁😁😁.

If you have been waiting for our ball bearing version of our 2015+ WRX turbo. The wait is over. Introducing to the world, the SteamSpeed STX 71R BB turbo for FA20.

Here are some pics:

What you are seeing here is the ball bearing version of our STX 71 turbo in our FA20 compressor and turbine housings in the flesh..ur…metal.

The tricky thing about making this BB product was adapting the Garrett GT cartridge to work seamlessly with the other OEM parts like the oil sump. For these, we will be sourcing the CHRAs from Garrett Japan, but we replace the compressor wheel with one of our own design.

What is the benefit of JB vs BB? This is the question we get asked all of the time along with, is it worth the extra cost? We use the same compressor wheel for both BB and JB. We recommend BB:
– In the cases where the customer intends to be more aggressive with the turbo and therefore demand more out of the CHRA. The BB CHRA will be more durable.
– Where the transient boost is a factor
– Where there are problems with backpressure

We have now had 100s of turbos installed in FA20 over the past 9 months or so. A picture has begun to emerge of how to make power with the FA motors, and the limitations are starting to be well understood. On e85, our turbos can make well over 400 whp using the 67 wheel, and over 550 using the 71. These results are much higher than the STI versions of the same turbo. However, on pump gas, they often make less power than the STI versions. Why? The FA20 responds great to octane, and really suffers with low octane. The EJ25 is less impacted by octane.

The other big factor that hampers power with the FA20 is backpressure in the exhaust system pre turbine wheel. The OEM manifold is really restrictive. The twin scroll turbine housing also doesn’t flow as well as and as efficiently say a T3 housing. All of this results high backpressure, and in some cases very high pressure ratios in the turbine section. A good manifold will unlock power in the mid and top ranges with our turbo. Cams are also an option, but backpressure is a real problem for the turbo to be efficient. As you may know, if the turbo isn’t being efficient, it isn’t making the power it could.
This is where the BB CHRA can provide a real boon for FA20 owners. A BB CHRA can stay efficient even when there is a ton of back pressure. JB turbos stay efficient only nearer to the idea ranges of backpressure. Also, if there is a lot of backpressure, like with the FA20, the BB CHRA will be more durable and last longer than a JB CHRA.

For EJ25s, back pressure and octane is isn’t such a big deal as it is with the FA20. It isn’t hard for most tuners to make great power with either our JB or BB turbos for STI. We expect that our BB FA20 turbos will make it so that customers will be able to get better dyno results with less effort from the tuners because they are more efficient against sub-optimal conditions. We expect to see higher average numbers with the BB version, and require our customers to have less supporting mods to get there. Imagine what your WRX will be like with one of these guys installed.

What do you what to know about these guys? What are your initial thoughts?