This page will detail the installation of a T3/T4 turbo
in an omni. After doing much research, and talking with
Chris at Turbos Unleashed
I decided to go with a Turbonetics
T3/T4 Hybrid turbo with a TO4E compressor housing, and a 50 trim compressor
wheel. The Turbine side has a Stage II wheel which
was recommened due to realivly quick spooling, while
still alowing for a great deal of exhaust gas flow. This compressor wheel should
be able to support close to 500HP at the flywheel.
I will be quite happy with 300-350HP on race gas.
Note that I do have a ported head, intake, and exhaust manifolds.
I dont think that I would go with a turbo this size
unless this was the case. I had a T4 wheel in the stock
compressor cover with at stage II turbine wheel last
summer, and it did not spool up until about 4200 RPM.
This was without a custom cal, but none the less it gives you
an idea of how the power band is pushed to the right.
The following images show the initial mock up for the
waste gate actuator bracket that I will be making. This
one was used to rough out where I will place the bends
so that the large waste gate that I have will bolt up
to the stock swing valve flapper. Although Brackets are available
from Turbos Unleashed for a mere pittance, I decided to
make my own since I will be making just about everything
else for the car. In retrospect, I can already tell you that
the $15 is well worth it.
Here are some pics of the actual bracket that I will
be using. I will probably trim it up some around the
wase gate, but not too much as that might compromise
its regidity. The arm is adjustable, however I will
most likly not need to shorten it, as the lowest
boost I could get out of the turbo that it was on
when I had my turbo coupe was 12PSI. I think it should
be capable of holding all the boost I can throw at it.
NOTE: The compressor housing had to be clocked ever so slightly
to avoid contact with the starter, and a new bracked had to be
fabricated. I would again recommend picking up the $15 bracket from
turbos unleashed unless you too are going for the bragging
rights of making absoulutly everything possble on you Omni.
This shot shows the turbo attached to the head.
Note the oil feed line is forced to face roughly parallel
with the long edge of the head due to the fact that
Turbonetics turbos come with a oil filter attached to
the cartridge. This caused the line to hit the intake
maifold in any other postion. As a result the oil feed
line that I purchased is about 4in. too short to reach
the oil distribution block that is attached to the engine
block. I will be using a section of line and XRP fittings
that I picked up at J&H hydraulics in Madison Heights MI. Their number is
248-543-8324. They are very reasonable and knowledgable.
NOTE: I had to clock the turbo so that the oil train tube
would hook up to the center section of the turbo. This caused the oil feed fitting at the center section to hit the intake, and would not allow the
turbo the be properly clocked. I had already made up my section of braided line, but That was
worthless unless I would be able to clock the turbo to make the drain tube line up.
I solved this newest delema by using a 90* 1/8 NPT to -4AN fitting right into the top of the
oil filter which came attached to the center section of the housing. this actually allowed the clearance
for the line to be routed the way it was intended, and the extra piece of line was not needed.
Note that I decided to grind the area higlighted due
to seeing the close fitting nature of this area on The
UPDATE: I have driven the car for about 150mi. with the new setup, and
I love it. See the Black Death
page for the overall specifics. Boost comes on at right around
2500RPM, and it pulls hard until the clutch starts slipping which is a real downer.
The wastegate bracket that I ended up making works quite well
altough the minimum boost setting is almost 15PSI.
It was a great deal of trouble and frustration installing my
first hybrid turbo, but it was well worth it, as the car is
putting out noticably more power than last year much sooner.
To se pictures of the IC piping, and a good view of the turbo in the car check out the Spearco IC install page.