Oh Paul you old tease ...
If your existing springs are perfect then you can use the measurements off
them in the program, but if your existing springs are perfect you wouldn't
need to! Because the spring free length and tension is what changes over
time you would have to use a combination of some measurements, original
curve data, extrapolation from graphs based on a handful of examples,
subtract the effects of the primary spring to get the secondary spring data,
convert from Imperial to metric, before you can use the program. Then to
get the spring you have to cough-up 70 of your hard earned quids just to get
Southern springs to set up a machine to produce the first half-dozen ... and
that is just for one of the two springs! Given the 20+ different curves
just for MGBs and the consequential low market for each spring, even given
that a few might be common to more than one curve, I would want cash in the
bank from prospective purchasers before I placed any orders with Southern.
And after all that measurement of old units, extrapolation from graphs based
on a handful of examples, conversion of numbers etc. I just wonder how close
the end results would be. Even then, as I have said many times, fuels and
most engines are today very different from when the curves were first
determined, and consequently significantly different from the ideal curve
for the engine today. You would be better off doing what Marcel Chichak
advises in one of his papers and that is spending your money on a rolling
road instead and getting a curve for your car. Or getting John Twist to do
the tweaking from a handful of 'standard' springs to get the original curve.
Personally I'd like to have a knock-sensing retard system and do away with
the existing centrifugal and vacuum mechanisms altogether, and end up with a
system that not only takes account of all possible variations in fuel,
engine, load, throttle opening, revs, and even altitude!
PaulH.
----- Original Message -----
From: <ptegler@cablespeed.com>
To: "Paul Hunt" <paul.hunt1@blueyonder.co.uk>; <mgs@Autox.Team.Net>;
<difejo@optonline.net>
Sent: Wednesday, September 29, 2004 2:59 PM
Subject: Distributor advance springs - pick your own
> ... From there, you'll see what the lengths and strengths of the springs
> need to be...
Check out the new British Cars Forum:
http://www.team.net/the-local/tiki-view_forum.php?forumId=8
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