I turned my attention to the passenger side turbo today. A test fit of the Turbo Concepts turbocharger showed that I’d need to do some work with the file on this side as well. In this case the issue was with the wastegate canister and bracket.
Turbo Concepts wastegate canister
After snugging the turbocharger into place I had a couple marks for where I’d need to file out some material.
The bracket is straight forward enough, I also cleaned up a portion of the bracket that sits close to the starter just to make some additional clearance.
With the can I only removed a little bit out of concern that I could break the airtight container.
I also saw that the nipple off the wastegate can was pointed more toward the exhaust manifold than the BorgWarner K04 wastegate is.
Turbo Concepts OrientationBorgWarner RS4 K04
With these tweaks behind me I believe I am ready to move forward with installing the Turbo Concepts Turbochargers.
Prior to installing a turbocharger on my S4 I make an effort to flow test the turbine side to see how it compares with the other turbochargers that I have tested.
For this test I run a 100 CFM calibration plate since it is the closest to where these turbo products fall out, generally around 45-55 CFM at 28″ of H2O.
Turbo Concepts Stage 1 Turbocharger on Flowbench
After performing the bench calibration I place the turbocharger onto an adapter for transitioning to the flowbench. The compressor wheel is fixed in place, I hold it still with a finger, and then I slowly run the flow bench up to 28″ recording several data points along the way.
The chart above is a consolidation of the various turbochargers that I have tested thus far. Of note, the BorgWarner RS4 K04 has been the highest flowing turbocharger that I have tested.
The Turbo Concepts Stage 1 performed similar to the FrankenTurbo and Turbo Engineers products, as well as BorgWarner K03’s, still below where the K04’s placed.
While this is a test that I don’t put a lot of stock in to give insight into how the product will perform on the car, it is notable that the exhaust backpressure measured on the vehicle has been lowest with the BW K04’s, supporting the flow bench measurement.
Several months ago I mentioned that Turbo Concepts was a vendor I was interested in learning a bit more about. The information I could find at the time was looking promising based upon the marketing information, but I was hoping to find some user data on the Stage 1 offering.
Turbo Concepts DZX-271
Turbo Concepts (TC) was cooperative in providing me with some on car data, unfortunately the results were from the middle of the summer (hot temperatures), and on a Tiptronic equipped car, so the tune was not very aggressive. The information was inconclusive; it did not show the turbo’s being able to produce full boost by 2800 rpm, something the larger Stage 2 turbo is claimed to do and so a benchmark that I would expect the smaller Stage 1 turbo to equal, or exceed.
For reference, BW K04’s under favorable temperature conditions can reach 20 psi by 2800 rpm. The BW K04 is also advertised to flow about 21 lbs per minute, by comparison the TC Stage 1 product is claimed to deliver up to 28 lbs. per minute.
Outflowing the BW K04 yet retaining the same response is just what I have been after as part of my search for the best stock motor turbo. A search that has yet to uncover a turbocharger capable of equaling the responsiveness of the BW K04. The Turbo Concepts Stage 1 turbocharger is unique among turbochargers I have come across as it is targeted as a direct replacement for the RS4 K04. During my search of the K04 alternatives the information I have found shows that most of these K04-hybrid options are a decent bit larger than RS4 K04’s, and so far have failed to meet RS4 K04 responsiveness.
While inquiring about the TC Stage 1 product they had informed me that they were in the process of incorporating a revised turbine wheel design in their products and that the new turbine wheel was expected to bring an increase in responsiveness, this was encouraging news.
The Stage 1 turbochargers are now available with the latest turbine wheel and I’ve decided to see if this product lives up to the manufacturer’s claims, those being:
BorgWarner RS4/K04 responsiveness
Outflow the BorgWarner RS4/K04 by 20% (28 lbs/min)
Up to 450whp on pump gas
I also plan on assessing how it compares with the other turbochargers I have evaluated on my B5 S4.
The following are photographs of the Turbo Concepts DZX-271 Turbochargers that were delivered.
