:-) I've simply purchased 'shorter' springs and tweaked them myself.
It was relatively straight forward. Fro mthe Lucas tuning manual
you have most of the info needed to calc. the basic spring requirements.
I use a pair if needle nose pliers and/or cutters to 'expand' a coil or two
and I was in business. I bought like 10 springs or so. I've now gone
through about 6 sets. (two wasted in experieiments over doing it)
I've used these in both Lucas AND Delco distributors to change
curves with great success!
Paul Tegler
ptegler@cablespeed.com
www.teglerizer.com
----- Original Message -----
From: "Paul Hunt" <paul.hunt1@blueyonder.co.uk>
To: <ptegler@cablespeed.com>; <mgs@Autox.Team.Net>
Sent: Thursday, September 30, 2004 6:15 AM
Subject: Re: Distributor advance springs - pick your own
> 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.
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