Band of International Boost Thieves Thwarted!

[Dan Stokes]

Those of you not at The Ohio Mile won't be aware of this but we were unable to attain the goal of 15 PSI of boost on the ol' Benz Diesel in Mutt. After much headscratching and guidance from Tim at Tim's Turbos (he built the turbo on Mutt - it features a T03 compressor and trimmed wheels) we came up with a test plan that I carried out at Carolina Dyno here in Wilmington. BTW - nice facility and helpful folks. They have a 4 wheel (not needed for Mutt) Superflow with Eddy current absorbers so they can do steady state testing such as required for this program.

The plan:

1) Do a pull with no boost reference from the intake manifold to the wastegate. This should yield all the boost that the turbo can produce.

Test results: 20 PSI at 4400 RPM, 30ish PSI (the gage was pegged) exhaust pressure, ~660 EGT

2) Hook up the Vibrant boost controller and adjust to 15 PSI boost pressure.

Test Results: Unable to get more than 8ish PSI under any circumstances. Exhaust pressure was about 12-14 PSI, EGT pretty constant at ~660.

We determined that the Vibrant controller was Kaput. Actually, never any good as it was new for this build. After some rummaging at Carolina Dyno they found a (seemingly) new Turbosmart controller. Not sure exactly how this one works, but.......

3) Replace the controller and do a pull.

Test results: After minor adjustments we attained 15 PSI and more is available if I want to push it later. It WORKS!!!!! EGT still about 660 F and exhaust pressure at 20ish. PSI.

And Tim - Thanks SO much. Feel free to post this in your "Attaboy" section on the website.

Happy Guy!!

Dan