You have an article on your site Butterfly Effect
- "Active Exhaust Systems' latest electronically-controlled exhaust
butterfly..." How can I get more information on this valve and a price for
Contact Active Exhaust Systems Australia at firstname.lastname@example.org or
HyperFlow Technologies at http://www.hyperflow.com.au/
you know of any electronic products that show intake airflow in cfm, etc?
There is a variety of ECU reading software that will give you engine airflow
data - assuming you own a relatively late-model vehicle. For more details, check
out Reading Your Car's Brain - Part 1
and Reading Your Car's Brain - Part 2
More on EWPs
A newspaper appeared last week stating that Davies Craig has won a contract
to supply electric water pumps to the manufacturer of the forthcoming Connaught
GT coupe in Britain. Apparently, there will be several more production cars with
these Davies Craig pumps fitted as OEM due over the next twelve months. BMW
already uses an EWP in its 3-litre engines, but Davies Craig believes that it
breaches their patents.
Are you able to offer us readers a brief rundown on what happened when you
tested the EWPs? Surely there must have been some positive points - otherwise
why would car manufacturers pursue the R & D into it? Perhaps see if you can
do an article on retro-fitting a BMW unit?
We have not had any more experiences with EWPs since our original article in
2000 (Testing the Davies Craig Electric Water Pump - Part 1)
and we are unable to present any of our test data.
Re Electric PS Search
In reference to your "Response" column this week - Response.
There was a query about electric power steering. I know that 1989 model Suzuki
Alto Works I.E. have a setup that looks very similar to the picture. Cars
equipped with this feature have a ‘power steering’ sticker on the rear hatch
glass, a control box under the driver’s seat and a heavily different loom to non
power steer cars
Some Extra Nuts and Bolts Info
I've just read your article All You Need to Know About Nuts & Bolts
It was generally a very informative article, however I did notice a few
omissions that might require some clarification. I run the mechanical
engineering department in the company I work for and thought I might throw in
You have gone to some trouble to describe the differences between the
imperial fasteners "grades" yet you only mention metric "class" 8.8 steel
fasteners. Metric fasteners are generally available in class 4.6 - a lower
tensile strength grade. Class 8.8 fasteners are commonly available and are
regarded as the lowest grade acceptable for structural applications. Class 10.9
is also available as the high tensile variant. As can be noted from the table in
your article, class 8.8 is quite different to imperial grade 8 - the numbers
must not be confused in structural applications!
It is worth noting that some types of fasteners are only available in certain
classes - for example, socket head shoulder screws from quality manufacturers
(such as James Glenn and Unbrako) are typically class 10.9 only. Likewise, you
didn't identify preferred sizes. I recall in a recent article Julian noted that
he was forced to rework because he chose to use M8 x 1.0 rather than M8 x 1.25
Technical drawing books such as "Technical Drawing" by A.W. Boundy, or
"Technical Drawing - General Principles (as 1100.101-1992)" released by SAI have
tables detailing which metric thread sizes are preferred within Australia.
In general, unless it is required for engineering or functional purposes,
*never* use fine pitch threads as it will be very difficult to obtain fasteners.
Sizes that are commonly used in general mechanical engineering include M4 x 0.7,
M5 x 0.8, M6 x 1.0, M8 x 1.25, M10 x 1.5, M12 x 1.75, M16 x 2.0. M7, M14 and M18
are generally not used.
BTW, if you are not already aware, the best global repository for all
information on threads is "Machinery's Handbook". This covers everything
from Metric to UNC, UNF, Whitworth, Acme and even Panzer thread information.
In All You Need to Know About Nuts & Bolts,
the links for the imperial and metric thread gauges point to the same place. I
want the metric one, please.
Thanks for that - problem now fixed.
Love the Lamp
the Zero Cost High Tech Interior Lamp
Thanks for yet another great idea - it's often the little stuff like this
that keeps me more than happy with the value of my subscription...
Although, I did not actually use my old scanner to make an interior light,
your article made me realise I could quite easily gut, rewire, and transform my
scanner into a light box for viewing slides and negatives, etc. (I'm mostly
done, I just need to figure out how to frost the glass.)
In use, the scanner lamp throws out a really nice light - it has me itching
to raid some second-hand stores in search of more old scanners as I can think of
several more things I'd like to make with them. I'm currently thinking a compact
portable work light - perfect when working under the dash and there isn’t enough
room for the usual oversized auto lamp.
The only thing I came across with my lamp that differed from yours was that,
when using it with a mains powered DC pack, my light wanted the full 24 volt
500ma supply from the original scanner - anything less gave a very dull
Excessive Drivetrain Loss?
In relation to the article of the 3.0-litre turbo Supra engine - 7MG Mega Motor!...
The power at the wheels is stated as being 570hp. The flywheel figure is
quoted as being calculated at 850hp (or even closer to 900hp). Surely, the car
would not be losing 280+ horsepower through the drivetrain?
Fergus O' Connell
The old fashioned auto trans would be responsible for a sizeable percentage
power loss but, equally, the car is difficult to run on the chassis dyno due to
tyre slippage – so the 280+ hp loss is an estimate based on these factors.