Andy,
This is a follow up on Ray's suggestion to dynamically time your Pertronix
ignition at full advance. According to my workshop manual, 32 degrees full
advance is specified for the TD. No engine speed is given. In the section
on TFs, however, 25 degrees is stated for the TF at 3100 RPM. Based on
this, I think you would be OK if you timed your TD at 32 degrees, 3100 RPM.
To get the proper distance from the TDC mark on the pulley (for 32 degrees),
measure the diameter of your pulley and multiply by .278. If you have one
of the new fancy timing lights (spelled expensive), you can read the degrees
directly without measuring the pulley.
Although the method of timing described by Ray is better, your original
scheme shouldn't have been that far off. I doubt if very much advance would
have kicked in at 800 RPM. To play it safe, follow Ray's advice and time at
full advance.
Ben Prince
54 TF 1500
----- Original Message -----
From: Ray McCrary <spook01@home.com>
To: Andrew Moyce <amoyce@pol.net>; <mg-t@autox.team.net>
Sent: Friday, June 23, 2000 8:13 PM
Subject: Re: Timing the Pertronix ignition
> Why not just adjust the timing so that total crank degrees of timing is
> achieved, and let the idle timing take care of itself?
> By this I mean that you know that it takes a total of, say, 32 degrees
total
> (crank) advance at 3000 rpm to achieve maximum performance. You set the
> distributor to give 32 degrees at 3000 rpm, and let the timing at idle
fall
> where it will.
> BTW, the 32 degrees is just an arbitrary figure that I have used on other
> engines; you will have to determine total advance on the MG distributor
from
> a Lucas manual or other info source.
> Best,
> Ray McCrary
> "Speed is Life;
> of course Luck and Altitude
> are helpful, too."
> ----- Original Message -----
> From: "Andrew Moyce" <amoyce@pol.net>
> To: <mg-t@autox.team.net>
> Sent: Friday, June 23, 2000 7:19 PM
> Subject: Re: Timing the Pertronix ignition
>
>
> > I'm still having some minor timing problems with the Pertronix. I
> > haven't been able to static time, using either light off or light on
> > as an end point, so have to resort to timing light. The problem,
> > I've been told, is that above 6 or 700 rpm the spring weights come
> > into play, so the setting will be a little retarded.
> > I currently have it set (idling at about 800) at a few minutes
> > before 11 o'clock . . . assuming TDC is 12 o'clock. Runs okay, but
> > I'm getting gear lever rattle on acceleration. The rattle wasn't
> > there when I had the timing set closer to 11:15 or 11:30. Should I
> > go back there?
> >
> > Andy Moyce
> > 52 TD
> >
>
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