Eric,
have you done head work to the car? The brow in the combustion chamber
between the valves can get so hot that it will glow and thus cause
preignition. Obviously if the engine is cold then this point will not be
overly hot to cause problems. AFIK it is standard practice to remove this
point whenever any head work is done. Since this is your race car I would
not be surprised if this gave you problems.
james
----- Original Message -----
From: Telewest (PH) <paul.hunt1@blueyonder.co.uk>
To: Eric <eric@erickson.on.net>; MGS <mgs@autox.team.net>
Sent: 25 April, 2002 12:17 PM
Subject: Re: Think pink
> If the engine were 'cold', even if not cold enough to need choke, it is
> still much less likely to pink then when fully up to temp, even though the
> usual cause of pinking is over-advanced ignition. Over-advance can come
> about simply be being out of adjustment, if the centrifugal advance
springs
> are worn, broken or displaced causing max advance to be applied at far too
> low an engine speed, or an incorrect distributor and/or vacuum advance
> capsule. If your '98' is the same as the UK 98 you shouldn't have any
> problem pinking. Do you get running-on?
>
> ----- Original Message -----
> From: "Eric" <eric@erickson.on.net>
> To: "MGS" <mgs@autox.team.net>
> Sent: Thursday, April 25, 2002 8:07 AM
> Subject: Think pink
>
>
> > My car is tuned the way I like it for fast street stuff (if 'fast' isn't
> > too much of a stretch for a nearly stock MGB) and some track work. This
> > means, however, that she pinks badly and load on fuel under 105 octane.
> >
> > I run her on AVGAS 105/110 for best results (if I drive carefully she
> > goes OK with the 98 octane stuff they are now serving from pumps around
> > the place).
> >
> > Something I noticed the other day prompts this mail.
> >
> > When I take off in the morning and the car is cold I naturally don't
> > push her too hard until she is really up to 'driving temperature'. The
> > other morning I needed to put the foot down to avoid someone doing
> > something silly and I happened to think about her pinking - there was
> > none even though she was right down in revs (below 2000) when I put the
> > foot to the floor. Usually this would sound like I was dragging a chain
> > down the road.
> >
> > So, why would she not ping/pink/pinque (!) when cold as she does when
> > hot/running temperature?
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