Things progressed this weekend with the TTE550 turbochargers, but it’s been a bittersweet continuation of the project with the sudden unexpected passing of “Daz Dillinger”.  Daz is a person with whom I have partnered on several projects since we were first introduced several years ago.  It has been his knowledge and generosity that have provided the foundation upon which this project, as well as others, have been built.  I will have more to say about Daz’s work with me in a separate posting.

The first drive with the TTE550’s has been successful, although with two issues to address.  First was a high pitched siren sound when boost hit about 20 psi, something I immediately thought was a boost leak.  After hooking up the boost checker I confirmed my hunch, that yes there was a hose clamp on the upper passenger side intercooler that was not tight enough.  It was a relief to have the problem be located in such an easily accessible location.

The second issue, which is a known obstacle to overcome with the changing out of turbochargers, is that the TTE550’s use an 8 psi-preload on the wastegates, and the FT21’s used about 14 psi.  Thus the tune now will under-boost on account of the wastegate differences.