Barina SRi Updates
I am a subscriber and
love your work.I have recently bought a new Barina SRi (I
read your 2002 review - New Car Test - Barina SRi) and would like to know what technical changes were made for the
post-2004 model -
I know they tweaked the steering, deleted traction control and upgraded to 16
inch alloys. I tried talking to Holden but they said they could not give me
any press release
information and
that I should try
a motoring
editor.
Bruce Carter
Australia
Aside from the changes you mention, the only other major alteration to the
’04 model was the introduction of brake
assist.
Re SR20DET Guide #1
In your SR20DET article The SR20DET Guide you say...
"Inside, the GTi-R engine has numerous improvements over
conventional SR20DETs. The
bottom-end boasts piston oil jets, a larger capacity oil pump with a water-to-oil cooler as well as
stronger main cap bolts
and conrods. The top-end features beefier head bolts, sodium filled exhaust valves, a revised exhaust cam
profile, solid lifters, an
improved head design and different piston crowns providing a static compression ratio of 8.3:1
(down from 8.5:1). "
The SR20DET from my S14 had piston oil jets, sodium filled
exhaust valves and a
water-to-oil cooler. I believe all SR20DETs have the squirters and
sodium valves but the S15
(5 speed) engine that replaced mine doesn't have a water-to-oil cooler.
Avner Bronfeld
Israel
Thanks for that – interesting stuff. Can any other readers identify the
internal differences between the regular SR20DET and the GTi-R
version?
Re SR20DET Guide #2
Re your SR20DET Guide...
Being a past Pulsar GTi-R owner this article captured my eye immediately, so I had a look (as I always do at lunch time) and I noticed you omitted one SR20 engine variant.
Although not a SR20DET as such, you forgot to mention the last of
the SR20 turbo
engines – the SR20VET, as
fitted to the Japanese-spec Nissan X-Trail
(GT, I think). From
memory, this motor puts
out around 206kW and has
Nissan's NEO VVT technology.
Gino Espinosa
Australia
You’re right. As far as we can determine, the SR20VET (fitted to the 2001 J-spec
X-Trail GT) uses a relatively high 9:1 static compression ratio and NEO VVL
(variable valve lift) to generate a massive 206kW and 309Nm. Unfortunately, we are yet
to see this engine at the import wreckers.
NVH Shootout?
I was wondering about the possibility of a "NVH shootout"
- a quest to find the smoothest, quietest and most refined driving car.
I'm sure Julian Edgar’s Lexus LS400
would be a likely participant!
Peter Parianos
Australia
Such a test would be very difficult – you’d really need to have all cars
together at once for SPL measurement and subjective testing. The Lexus would be easily outclassed by some current cars.
Speed Signal Problems
I have just purchased a Nissan Skyline R33 (1993) which was originally
an automatic. It has been changed to a manual, but
the problem is that the
speedo only shows about half the speed you’re really doing. In addition, the odometer and trip meter
readings are out. Can you help us sort this
problem out and let us know what is required to fix
it?
Greg Dixon
Australia
We suggest altering the vehicle’s road
speed signal using the Silicon Chip Digital
Speedo Corrector (as sold through Jaycar outlets.)
Electronic Kits Separable?
I just bought High
Performance Electronic Projects for Cars Book Review - Performance Electronics for Cars. I know that
I can buy the kits from the AutoSpeed shop and build
them myself, but the problem with that approach is
that I might have to pay 60 percent import tax.
I did some research and found out that all the
electronic components
that I need can
be purchased
here – however, I noticed that for the PIC projects I
need the assembler program
that goes inside it. So my question is... Can I get these assembler files for all projects or
do I have to buy the complete
kit?
I know that there are advantages to buying the complete
kit approach (the PC board will be much cleaner that the one I will build) but, still - to have
the book and not be able to build yourself the
kit (by purchasing the
parts myself
over here) is a bit
frustrating.
For a long time I wanted to sign up to AutoSpeed and I’ve now been able to
do it. Congratulations for the nice papers you
guys put together - always
very technical. Keep doing
the good work.
Carlos Dagher
Brazil
The assembly code is not available so you will need to purchase the complete
kit. Glad
you like the articles!
Diesel Myth
Hi there! I am driving a diesel vehicle and there is a myth going around saying that it is not advisable
to drive until your
fuel tank is near empty. This is because diesel
(being a lower quality
fuel) leaves deposits in
the fuel tank and driving ‘til near empty
will pick it up in the
fuel pump. This is the
common cause of fuel pump damage.
But is that true? The
pump’s fuel inlet is
located at the bottom of the tank and thus everything will be picked
up - no matter
if the tank is full or empty.
Please enlighten us and smash the myth!
Lee EK
Singapore
We can’t offer a definitive answer, but we believe a low diesel fuel level and
high humidity encourages the growth of algae. This might be the reason for this ‘myth’.
More on Plumbing
Reading your article Plumbing Basics, Part 3 brought back memories of adding an intercooler to my 1986 Mazda 626GT. The
intercooler was mounted
almost horizontally (30
degrees) beneath the battery - a scoop directed
airpassing beneath the
car into the core. A
single length of 1 3/4 x
24inch BellowsFlex hose
was used to connect the turbo to the intercooler
and a second length of 1 7/8 x 36 inch hose
connected to the
throttle body. There
were no sharp bends or
material transitions to disturb the laminar flow
along the way - just a
smooth continuous hose. How many other systems can say that?
BellowsFlex (yellow stripe) and other similar brands come in many sizes and,
despite having an interior spring coil, the interior wall is smooth. The
inner liner is oil-resistant
Nytrile B, capable of withstanding pressures of 30-50 psi and has a working temperature of 110
degrees Celsius. At the time I payed
US$3 a
foot (about 30cm). Turbo and High Tech
magazine also published my
626GT as a Readers Car
in May, 1989.
P.S. - I've built your
fusion IC which will be installed along with a BPT engine/tranny in
a ‘88 Mazda
323GTX this winter. I'll
write you when it's running! Thanks for all your thought-provoking
articles!
George Barrett
USA
Interesting stuff. Let us know how you go
with the fusion IC!
More on Prius Fuel System
I would like to say well done on the modifications to increase fuel pressures in
the Prius. I would just like to put forward a
simpler idea that
I believe would increase
the fuel pressure - but
possibly not as much as
you achieved. Does the Prius have a constant voltage sent to the fuel pump? If so, I’m sure you
could increase the flow and pressure to the fuel rail by increasing the voltage to the pump up
to, say, 20V. This might not sound safe for
the pump windings but I’m
sure for street cars (since boost is not held on for long compared to a race car) that the increased heat in the windings should not be an
issue. Furthermore,
products already exist from MSD that use a boost signal to ‘overvoltage’ the
pump, such as this one... www.msdignition.com
(the 22V 10 amp output one).You
could add some additional circuitry to cut out the oxygen sensor signal or make the fuel pressure
increase in a step change from baseline. Furthermore, you
could use the Silicon
Chip PIC based micro-controllers and adjustable fuel tables to
modify the voltage coming out of the voltage
booster to the fuel pump.
Jim Katsis
Australia
Check out the article Modifying Returnless Fuel Systems, Part 1 - the MSD Fuel Pump
Voltage Booster is mentioned there. Certainly, these
units can be used to bump up pump
output, but you’re still limited to the fuel
pressure which is dictated by the pressure reg. We needed a way to increase fuel
pressure from around 44- 50 psi to around 85 psi - a big
difference.