NB SP $5 T-Piece Modification

[SPy vs. SPy]

open bonnet

observe pipe that runs from intake plenum to bypass valve (BOV) (the small one)

observe pipe that runs from output of turbo and waste gate (slightly thicker than the other one)

to do it, tap t-piece between intake and bypass (BOV) run middle bit back to waste gate of turbo.

plug up line on the pressure sensing side of the turbo output i.e the other end of the old waste gate line.

close bonnet

drive around block with extra 1-2lbs boost

Expect 3000 different answers as to whether this is recommended or not.

Bigdog and Dave have had this for eons, I believe Dave's runs aftermarket Chip setup, with a few more lbs thrown in.

Black SPy has had this for eons plus other goodness, part of which has failed at some point taking with it Number 3 piston, currently awaiting rebuild.

SPy

[bigdog]

Note T piece on vacuum line:

Line from manifold at top is plugged with bolt and hidden under strut brace, wastegate line runs to T piece in pic above.


5 mins to do and 146RWKW as a result

[Garry]

Why not do it properly and get an EBC? The boost in my car comes on much smoother and therefore it's much easier to drive in the wet than it was without it, even running more boost than the t-piece gave me. You can also tailer the boost to the correct amount for you tune rather than get pot luck with the t-piece.

I tried the t-piece on my car and didn't like it. Apart from my car pinging the boost came on much more abruptly than without it.

Of course an EBC will set you back several hundred dollars and the t-piece costs around $5.

If you do decide to go the t-piece then pay special attention for any pinging. And make sure you get the plumping right or severe engine damage may result.

[kazjim]

With the Turbo Mini, i actually built a "Dial a Rebuild"

basically, i ran a t-piece as described above, but then i ran a line to a vernier needle valve (From a hydraulics shop), and then ran the other side of the valve to a restrictor (1.5mm carby jet!) and from there to a filter in the air-box....

Basically without the restrictor the valve was not able to make large enough changes in airflow to make the wastegate changes required .... the restrictor stopped all the compressor air from running out the valve and the wastegate never opening !

you will need to experiment with the restictor size, but using this method i was able to go between 6PSI (Stock wastegate spring) and 20+PSI (wide open valve)

And the best part was that the delivery appeared to smooth out, and the boost came on even stronger higher up in the revs !

the second build of that engine i trialled a TurboXS Boost controller, and to be honest, even though the TurboXS one cost a LOT more, the home made was a lot more effective !

Cheers
J

[Daz]

My original post on it is here.

There is 11 pages of debate and the photo/install detail is on page 5. Cant believe that's 2.5 years ago !

I was going to install an Apexi boost controller, already forked out ($600?) the money for it and decided to try this first. I never looked back, the car ran perfect, no pinging (it never sees <98 fuel though) and the boost controller was on ebay the next day !