TTE 550 Another Contender

The longer I wait the more interesting things become.

Another option that I’ve recently been made aware of is a product from The Turbo Engineers, an outfit in Germany.  While they have a large product line the turbocharger that caught my attention was the TTE 550 (image below).

The Turbo Engineers TTE 550 B5 S4/RS4 Turbocharger
TTE 550

This turbocharger pair is based off of the BorgWarner K04 with modified RS6 internals.  It’s a pairing of components that I have heard good things about and one that I think provides a great upgrade path to someone with K04’s that would like to max out their stock motor, or even push a little closer to the 500 whp range.

For less than the cost of new turbochargers TTE modifies the used BW K04’s, milling the compressor housing so that RS6 internals can fit into the K04 housings.  This means the turbo’s go right back where they came from in the engine compartment without need to purchase RS6 turbine housing compatible DP’s.

TTE offers a number of additional modifications for this turbo such as:

  • Ported exhaust entry
  • Gasket matched exhaust flange
  • Ported boost outlet
  • Ported compressor inlet
  • Compressor cover painted in black Hi-Temp coating
  • Actuator painted red in Hi-Temp coating
  • Lightened Turbine wheels

I’d like to find some additional performance results from users of this turbo, but the data supplied from the manufacturer looks promising.

My list of turbocharger candidates now looks like:

  • BorgWarner K04
  • FrankenTurbo F21
  • ProjectB5 RS6-X
  • SRM Billet K04
  • TTE 550

Next: FrankenTurbo F21 Mixed Flow

PTP Turbo Blanket

My first foray into the market of turbocharger blankets was with the PTP Turbo Blanket intended for use on my Audi S4’s BorgWarner K03 turbochargers.

PTP Turbo Blanket

I figured that the turbine housing of the K03 was probably not significantly different than that other turbochargers I might soon consider using, BorgWarner K04’s, FrankenTurbo F21’s, SRM RS4 Hybrid, ProjectB5 RS4-X, etc, since all used the K04 hotside so that if I were to upgrade I might be able to reuse the PTP Turbo Blanket

After measuring the circumference around the turbine housing of the K03’s and a set of K04’s I found that they only differed by approximately 0.75″ which I believe is sufficiently close to not matter to how the turbocharger blanket performs.

Unfortunately the turbocharger blanket model I selected was not a good fit with the K03’s on the S4, more specifically in the area where the exhaust manifold attaches to the turbine housing.  After monkeying around with trying to get the blanket to fit I decided that major surgery, such as cutting the blanket to get it to fit, was out of the question and I would  return the model I had selected to PTP Turbo Blanket and investigate other models that they carry.

I also inquired with PTP Turbo about a custom blanket, which is something they offer, but they advised me that to produce a blanket for a single vehicle the cost would probably be unreasonable.

At this point I decided to expand my search to other product suppliers to see if another might carry something better suited to the BorgWarner K03’s.



Arriving today are a set of Silly Rabbit Motorsport SMIC’s in the RS4 configuration.  Thanks to SRM for attaching an Aquamist water-methanol injection bung to the upper end tank so that I can inject at the intercooler.

Stay tuned for flow test results…

Silly Rabbit Motorsport RS4 Plus SMIC Intercooler srm_rs4_smic_4 srm_rs4_smic_2 srm_rs4_smic_3