Posts with a significant portion of the discussion involving FrankenTurbo products
After getting my wideband O2 sensor installed I disconnected the electrical signal to the N75 so that I could check the boost pressure that the Mamba wastegates allow with just the preload.
I am glad to see a mostly consistent level of boost being held, but I had set the preload to 12 psi prior to installing the engine in the car so I was expecting to see closer to 12. I’ll next be double checking that the preload is equal between the two Mamba wastegates.
With everything back together took the car out for a shakedown drive to make sure everything was working ok. The tune is for the Turbo Concepts turbos with different wastegates and a higher preload setting. Will need to do some work on the boost control.
With a number of different turbocharger pairs sitting in boxes, and a good pair on the car, I’ve had trouble deciding what to do next with my S4.
Then there is an incomplete engine sitting in the corner of my garage that will open some opportunities on account of the 2.8 heads and built bottom end.
After several months of no progress on either I took some free time on New Years day to start preparing the car to pull out the engine.
The built engine is not ready so that option is out for now. My goal with the TiAL turbochargers is to have them made over into 770’s, so that leaves me with a choice between the BW RS6 turbo’s:
Or prototype FrankenTurbo F21 with ceramic coated turbine housings and Mamba wastegate actuators.
I’m leaning toward the F21s on account of them being an easy transition from the Turbo Concepts Stage 1 turbos that are presently on the car.
