Ignition Rotor weight springs.

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Barnfind
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Ignition Rotor weight springs.

Post by Barnfind »

Hello.
I recently found one of the ignition weight springs broken. Do any of you know a source for those? I have been llokng at Superformance rebuild kit, but springs are not shown.
Thanks..
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fdus172
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Re: Ignition Rotor weight springs.

Post by fdus172 »

Look closely at the picture with the Superformance kit - springs are included...

RickWohleber
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alh
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Re: Ignition Rotor weight springs.

Post by alh »

Springs are not "plug & play", you need to have access to a range of springs and a distributor testing machine to set up the advance mechanism properly. Just installing a set of springs without a testing machine could either lead to a too retarded timing (less engine output, slower throttle response) or to a too advanced timing (knocking, piston damage).
Barnfind
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Re: Ignition Rotor weight springs.

Post by Barnfind »

alh wrote:Springs are not "plug & play", you need to have access to a range of springs and a distributor testing machine to set up the advance mechanism properly. Just installing a set of springs without a testing machine could either lead to a too retarded timing (less engine output, slower throttle response) or to a too advanced timing (knocking, piston damage).
Interesting..

Obviously the same springs won't be exactly the same, buy will they differe so much?

I have a strobe light with timing and rpm, which helps for a basic test.. If the disteibutor follows the timing curve should be ok?

Regards.
Barnfind
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Re: Ignition Rotor weight springs.

Post by Barnfind »

fdus172 wrote:Look closely at the picture with the Superformance kit - springs are included...

RickWohleber
I see many small bits, but not the springs. Maybe the resolution of my screen is not high enough.

Thanks!
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alh
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Re: Ignition Rotor weight springs.

Post by alh »

Barnfind wrote:Obviously the same springs won't be exactly the same, buy will they differe so much?
I have a strobe light with timing and rpm, which helps for a basic test.. If the disteibutor follows the timing curve should be ok?
The springs need to fit the weight and wear of the advance weights and the condition of the distributor and weight axles. The springs have two lengths per side (inside and outside springs) but are usually all different in strength, catering to different areas of the advance curve. When adapting the springs you usually start with one or two springs for the initial advance up to around 2000 RPM, then with the third and four spring up to maximum advance. Depending on the wear you also need very thin washers to adjust the spring length.

To verify the advance curve, an adjustable strobe light with timing and RPM is fine.
Barnfind
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Re: Ignition Rotor weight springs.

Post by Barnfind »

I will have a closer look when I'm back.
could you post the advance curve for a 2400?

Regards..
Barnfind
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Re: Ignition Rotor weight springs.

Post by Barnfind »

Ok. I have documented a bit, and looks like my distributor has been altered. It has been reconverted to "normal" distributor style, with 2 springs. Now all that you said makes sense to me..
New parts are on the way. :)
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alh
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Re: Ignition Rotor weight springs.

Post by alh »

Barnfind wrote:I will have a closer look when I'm back.
could you post the advance curve for a 2400?

Regards..
Sure, here you are... the dotted line is measured without advance, the full line with 10º advance.
Both values are shown at the crankshaft.
Magneti Marelli S125 Advance Curve, Dino 2000/2400 Engine
Magneti Marelli S125 Advance Curve, Dino 2000/2400 Engine
Barnfind
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Re: Ignition Rotor weight springs.

Post by Barnfind »

Thanks a lot!
More work to do on the car..
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