Hi,
A V2 compressor wheel
profile machined into the original comp cover will give you aprox 300 - 350 RWHP at 1 bar of
boost given fuel is aprox. 11.5 AFR
under load, exhaust 3", etc match. The wheel is heavily back-cut. (see pix on website) I use 2 springs on the
backplate to strengthen the thrust.
On a bench drill I just drill a large enough hole to still leave a seat
for the flapper to sit on, I also keep
drilling untill I drill through the
scroll in the centre of the housing. Using a porting tool I further
enlarge the hole until its as large as
possible but still retains a smallish seat. A
larger flapper "disc" can be welded on but I've found its not necessary
in most cases as the above seems to fix
the problem. There are other options for
more power but the above will adequately fill your requirements very economically. If you find there is too much
torque for your buggy you could try a
Series 5 turbine housing which will transfer the power into the higher rev range but most people seem to love the
torque. The Series 5 housing has 2
flapper holes (Hitachi realised they had a problem) & the mods are therefore not necessary to the flapper hole,
but the housing is more offset &
consequently your engine pipe etc will move to the side a bit. You need
to lay the 2 housings side by side to
see what I mean or if you can't email me
back & I'll take a pix for you. I would stick to the Sreies 4 &
consider trying the Series 5 later if
necessary.
I charge $630 (+ 10% GST
AU only) for the above including reconditioning the turbocharger but freight is obviously an
issue from here as they are quite heavy.
Hopefully someone nearby can help you at a reasonable cost. I sometimes also get the comp cover "power
ported" or called "extrude honed" in the
States rather than change covers & backplates which helps
further increase air flow & helps
reduce inlet temperatures. Not so expensive here compared to the States I think, aprox. $180. You should also drill & tap a 1/8
Gas (NPT) thread hole into either the
turbine housing housing or exhaust manifold & test exhaustt
manifold pressure which should roughly =
boost pressure. You can put a 1/8 steel plug
back in the hold after finished testing. If you find exhaust
manifold pressure is too high (email me
with results if you like) you can machine a
bit of housing away around the turbine outlet blades, try about a
millimetre to gauge the differance.
Pressure drop across the intercooler shouldn't be more than 2 psi, a simple test & a
permanent pyrometer is a good idea with
the probe mounted about 2" behind the turbo in the engine pipe as
rotaries can tend to run too hot. I
don't like to see much more than 850c for
reliability although many race at 950c. The pyrometer can also be used
to help you tune the engine as we used
to use pyro's for this years ago before
Air Fuel Ratio Metres (AFR's) were invented. Finally you'll notice on the website
pix I machine the exhaust housing outlet
in a funnel shape (all above work done on a lathe except drilling flapper hole), to further help exit exhaust
gas, the angle I use is 7 degrees which
will still leave enough room for the dump pipe to seal although you may have to modify the gasket
& dump pipe should you find there
diameters
are small than the turbine outlet diameter after modifying.
Hope this helps & if you have any
further questions please fell free to ask.
Regards
Max Heywood ATS/Turbonetics
20a Assembly Drive,
Tullamarine, Vic.,
Australia, 3043.
Phone- 613 93351254
Fax- 613 93351264
www.turbonetics.com.au
----- Original Message
-----
From: "Schemmel, Grant"
<Grant.Schemmel@Aeroflex.com>
To:
<sales@turbonetics.com.au>
Sent: Wednesday, May 19, 2004 3:30
AM
Subject: 13B turbo
modification
> Dear Sirs:
>
> I was referred to your website
from a rotary newsgroup. I have a '90 13b
turbo engine which I plan to install
in an off-road vehicle, that will see
sustained 5000 - 8000 rpm use, low
rpm operation will not be a factor. I'm
hoping to set up the engine up to run
at around 220 - 250 HP. I understand
from the newsgroup that the stock
factory turbo will have a tendency to over
boost or creep. I also see from your
website that you offer turbo
modifications to take care of
this.
>
> So, could you give me an idea as
to the pricing of your services on an
existing turbo?
>
> Thanks!
>
> Grant Schemmel
> Penrose, CO USA
>