[Mgs] Overdrive Numbers

[Max Heim]

It probably makes more difference if you try to average 80+ mph (on I-5 in
California, for instance). At that speed the non-OD MG is well out of its
powerband and struggling (assuming the driver can even tolerate the howl).


--

Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the primer red one with chrome wires


on 1/15/08 2:52 PM, Aaron Whiteman at awhitema at panix.com wrote:

> On Jan 15, 2008, at 2:32 PM, Charles & Peggy Robinson wrote:
> 
>>    Tell John Twist.  He thinks overdrives are strictly "feel good"
>> add-ons.
> 
> That corresponds to my anecdotal experience.
> 
> Dads 1978 MGB got 28-31 MPG @ 70 mph on extended trips.  It had no
> overdrive and ran all day at 4000 rpm (or more, I don't remember the
> exact figure).
> 
> My 1975 MGB gets 26-30 MPG on the same trips.  It has overdrive and
> runs at say 3500 rpm.
> 
> The '78 had a 25D distributor and a downdraft weber and was recently
> rebuilt (less than 20K miles).  The '75 has a 45D with pertronix and
> dual SUs, but is pretty tired.  I need to get over and buy dad's car,
> if only for the engine.
> 
> My experience says the OD doesn't matter one bit regarding mileage,
> but when my OD broke and would not engage, it was disquieting for me
> to listen to the engine at the higher revs--even though I knew it was
> just fine.