I don't have a Pertronix in my TD, but Andy hit on a couple of issues I have.
According to the shop manual the high-lift cam requires a different dwell
setting, but darned if I can tell what cam my distributor has! The suffix
letter on my distributor is illegible, so there's no clue there.
Also, the shop manual has no mention of dynamic (strobe) timing. I've learned
the hard way that you can't trust static timing on an old worn distributor.
(Who cares what the timing is at zero rpm anyway.) To me static timing is
just what you do to get the engine started before you do the dynamic. Does
anyone have a set of timing values at different rpm's? Or better yet a curve?
(Sounds like Andy's satisfied with 5 deg @ 800 rpm, but I'd rather set it at
1500 rpm.)
In a message dated 5/31/00 4:47:59 PM !!!First Boot!!!, amoyce@pol.net writes:
> Just thought I would share my experience in installing the Pertronix
> in my TD. First problem started in selecting the correct unit. I
> looked at the illustrations in the service manual and compared those
> to my distributor cam but could not distinguish between asymmetric,
> high lift and whatever the other one was. I drove the car out to Skip
> Kelsey's, and we looked at it together and made an educated guess.
> Finally we decided on the asymmetric. When I got home and tried to
> slide the magnet over the distributor cam it wouldn't seat. It would
> slide over the cam but not far enough to allow the rotor to seat
> properly. I assumed I had the wrong unit. I exchanged it for the
> other unit (there are only two for the TD) and found that fit was
> worse.
>
> I talked to other members in the club who had installed these things.
> No one seemed to have experienced a tight fit over the cam. Finally
> with Skip's pen knife we whittled away at the plastic ridge inside the
> magnet and got it to slide down over the cam. The car started right
> up. I had about a three mile drive home before I could set the
> timing.
>
> I remember discussions long-ago about rattling in the gear shift lever
> being attributed to retarded timing, and I can attest that this was
> significant. Traveling uphill the gear shift lever sounded like
> marbles in a coffee can. I first tried to set the timing by the
> static method, but couldn't start the engine after three different
> tries. I finally resorted to a timing light, aligning the distributor
> to its original position, and then rotating it while the engine was
> running. I was surprised at how far off the timing was . . . actually
> advanced by about 80 degrees (360 degrees in a circle). With the
> timing light I set it to about five degrees advanced (rpm at 800)...
> rotating the distributor 30 or 40 degrees counter clockwise to do so.
> Now it runs like a dream. I used to think the engine was pretty
> smooth, but now it buzzes like a contented bee at all speeds. We just
> completed a 600 mile trip to Yosemite and back and it performed
> beautifully.
>
> So, installation was not smooth and easy, and I have a suspicion that
> I have the magnet misalignedd a bit on the cam, but the results are
> wonderful.
>
> Andy Moyce
> 52 TD
Bob Donahue (Still stuck in the '50s)
EMAIL - BOBMGT@AOL.COM
52 MGTD - under DIY restoration NEMGTR #11470
71 MGB - AMGBA #96-12029, NAMGBR #7-3336
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