Lawrie's answer sounds right to me. One more piece of information: Each
engine has its own unique power range. The Miata, for example, peaks, I
believe, around 1500 RPM higher than the B's powerband. The B engine is
known for having an unusal amount of low-end torque for a sports car, which
makes it very easy to handle in traffic of varying speeds.
Usually a perceptive driver can figure out the best power points through a
bit of experience. In most B's you don't gain too much by pushing the red
line, although as timing, ignition and carbs are changed, that also changes.
Let's not get into changing cams.
Jay Donoghue
72B
72B-GT
66 Mustang
In a message dated 00-11-11 01:14:19 EST, Lawrie@britcars.com writes:
<< Nina,
Yours are good driving habits - you've been shifting in the best part of a
B's engine's powerband to give adequate power combined with reasonable fuel
economy.
The Saturn's shift light has, however, a different purpose - to help owners
achieve the fuel economy advertised on the sticker that graced a window when
the car was new. I haven't driven a Saturn but my guess is that, driven the
way you drive your BGT, it would be a whole lot more fun but use a bit more
gas.
Lawrie
-----Original Message-----
From: Nina Barton <ninab@scoresheet.com>
To: mgs@autox.team.net <mgs@autox.team.net>
Date: Friday, November 10, 2000 10:03 PM
Subject: somebody explain shifting and RPM to me
>Hi List,
> I have always driven my MGB, and other cars, in the following
>manner. Start from stop, rev up to what seems an appropriate level
>(usually 3500 or so in the BGT), shift, rev up to somewhere around the same
>level, shift again, etc. I recently had problems with the troop carrier (a
>93 Saturn) which turned out to be that the bulb on the dash showing optimal
>shift for premium gas mileage had burned out. I didn't know it was there,
>as the previous owner had taped over it. It has now been uncovered, and
>besides being a pain in the a**, I notice that it suggests that I shift
>from first to second around 3000 Rpm, second to third at 2500 Rpm, and
>third to fourth at 2100 Rpm. Why? It seems like I'm not going fast enough
>in the car when the shift light comes on, much of the time, and it goes
>against my whole driving style. If one of the knowledgeable people on this
>list could explain why lugging your engine is good for the car, I'd like to
>know. Thanks, Nina
</XMP>
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