My TD is as your car. The later TD's used two springs of the same length and
gauge.
steve
52 TD
Bill Eastman wrote:
> Well, I have seen one brave fellow who offered up an opinion on why
> distributors have two sizes of springs. His was the explanation that I
> have heard many times before- that the light spring controls the advance
> at low rpm while the heavy spring kicks in at high rpm. Until a few
> days ago, I too subscribed to this belief. However, after some serious
> reflection time contemplating the insides of my spare dizzy, I think
> that there is a more likely explanation.
>
> If you play with your distributor on the bench, you will notice that
> there is s fair bit of slop in the mechanical advance system- the pegs
> are not a real tight fit in the advance weight grooves. So if both
> weights flew out at exactly the same time, this slop could allow some
> wandering of the timing or, at the least, some lag in timing change when
> the engine switches from acceleration to deceleration or vice versa. By
> allowing one of the weights to always lead the other, this slop is
> removed and the timing curve becomes crisper.
>
> Which brings me to a personal dilemma. When I had my dizzy apart last
> year, I noticed that one of the springs was a loose fit on its pins when
> stationary. I assumed that this was a bad thing caused by the spring
> stretching. Now I am not so sure and I am concerned that my shortening
> of this spring could have introduced some timing instability at low
> speeds. This could help explain the slightly lumpy idle the A has
> although the new street performance cam may also contribute. How about
> the rest of you? Has anyone else noticed one loose spring in their
> dizzy?
>
> After seeing very few MG's this year, I saw a red TD in Champlain and a
> very dark red (almost maroon) A in Edina in the past two weeks. Anyone
> I know?
>
> And for those of you who may have been going home on West 694 last night
> and saw a red MGA with a bent bonnet sitting dead in the middle lane, I
> just want to say that the traffic jam was not my fault! It started when
> a 56 Chevy that was two cars in front of me died. I stopped and offered
> help. We pushed his car to the shoulder then I went back to the middle
> lane to retrieve the A. I then tried to jump the Chevy and get it
> started. It turned over like mad but no fire. The Chevy owner had a
> cell phone so I wished him luck and departed. At no time did the MGA
> refuse to run. I half expected to see "Major traffic jam caused by
> unreliable British car" in the paper this morning but, to my relief,
> there was no major media coverage. One person at work has already come
> up to me this morning with some lame comment on British cars having had
> his afternoon commute spoiled. You can be sure that I set the record
> straight.
>
> Regards,
> Bill Eastman
> 61 MGA getting much more exercise again now the heat wave has broken.
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