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
>