[TR] Distributor bits

Carl TR cfmtr3a at verizon.net
Thu Mar 11 17:36:07 MST 2010

I was able to fix the clamp - will need to get an appropriate bolt/nut to 
replace the bent one- but otherwise it works.  (I used a long machine 
screw/nut and was able to tighten it down.)

The vacuum unit is toast. BPNW has them listed on their site.  But - I 
vaguely remembered a thread about distributor issues when installed on 86mm 
engines.  A search of the archives found:
Re: TR3A ignition timing
      from [Thomas Meise]

      To:  drew at pixar.com, triumphs at Autox.Team.Net
      Subject:  Re: TR3A ignition timing
      From:  Thomas Meise <tm at mk3.teuto.de>
      Date:  Tue, 14 Apr 1998 18:15:03 +0200

At 15:09 13.04.98 -0700, drew at pixar.com wrote:
>Well, looks like the shocks are looking good and I'm thinking about 
>(playing around with) the ignition timing. Does anyone know what the dwell
>angle for a 3A is? The manual says the point gap should be set to .015"
>but I've never felt comfortable with feeler gages. I seem to recall that
>the manual say to set the timing to 0 deg. BTDC and then to move the
>vacuum advance venier one mark BTDC which should yield 4 deg BTDC. Anyone
>have any other suggestions for setting the timing? There's been a bit
>of discussion on just advancing the timing until you get pinging under
>load above 3000 RPM. Is this what people refer to as setting the timing
>"by ear?" Is there a tutorial around anywhere on setting the timing?
>Thanks for any info,
>Drew Rogge
>drew at pixar.com

The dwell angle should be 60 +- 3.

First thing to do is to make sure that the right distributor is fitted.
The ignition timing depends on type of your engine specification. In case
of an 86 mm engine the summary of static, advance due centrifugal control 
vacuum unit should not exceed 26-27 degrees.

If there4s a wrong distributor fitted to your engine don4t wonder if it
doesn4t work. The distributor for the 83 mm engine has a advance timing due 
weights and
springs of max. 15 degrees. That4s  max. 30 degrees timing on the 
You must add static timing (4 degrees) and the advance due vacuum unit (
max. 15 degrees). That4s too much advance for an 86 mm engine .

The Lucas Part No. for 83 mm engine: 40403, 40480, 40698, 40783, 40850
                       86 mm       : 40735, 40795

So - how do I determine 1) if I have the right dizzy and 2) if not a source? 
Then I can re-think the vacuum unit.

Thanks again

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