My father's 1991 Chevrolet Silverado had the 85 MPH limit.

It is incorrect to say that they were "mandated".  They were *anticipated*
to
be mandated, but never were.

FloydR

I do not believe there is a fed regulation on it. I believe they do it
that way because nobody in there right mind is gonna drive 100mph.

Trucker sees another truck speeding down the hiway:
"Hey black KW how fast ya goin?"
"KW"
"KW? What the hell speed is that?"
"Hell if I know. The needle is resting over the KW logo at the bottom
of the dial."

The 85 mph speedometer regulation was proposed in 1976; adopted
during the Carter administration effective September 1, 1979;
and repealed as a result of Reagan's regulatory review effective
March 25, 1982.  I do not know whether the rule applied to
designated model years or to all cars manufactured between those
dates.

The same rule, FMVSS 127, also required tamper-evident odometers
on the theory that incorrect odometer readings were a safety hazard.
The odometer part of the rule never went into effect.

The notice of revocation of the speedometer rule stated:

   The agency's 1976 regulatory evaluation on Standard No.
   127 projected that the requirement that the limitation
   on the maximum speed shown on the speedometer scale
   would be five percent effective in reducing accidents
   involving young drivers. The projected effectiveness
   was based on the assumption that the 85 mph maximum
   speed indication would be a psychological deterrent to
   high speed driving. However, the agency has no data
   indicating that the speedometer scale limitation is
   effective to any extent in reducing the tendency to
   drive too fast and in reducing the resultant accidents
   and injuries. Also, the commenters provided no data
   indicating that the limitation had any actual effect.

My 1991 LX 5.0 also had the 140 MPH speedo. That narrows the range of
possibilities down by a year for ya. :)

And when some ZR1 owner kills someone by speeding, GM is gonna get
sued for making cars that fast and for putting in speedometers that
encourage speeding. GM is stupid.

My 1987 IROC Camaro has a 145mph speedo. I believe '87 was the first
year that was available; others were 85mph. And my 1987 Porsche 944
has a 160, which is a bit optimistic, but also used on the Turbo. Of
course, it's furrin'; the rules may not have applied to them.

Not exactly sure, but here's a clue from what I drove over the years.

My vehicles in HS and college were a 1971 Dodge Dart, a 1973 El Camino
(both with 120mph speedo's) and a 1972 GMC pickup (with a 100-mph
speedo).

Next was a 1981 Bronco with a 100 mph speedo.

Then was a 1989 GMC S-15 Jimmy with 85 speedo (though it was confirmed
to reach 103 once).

Then a 1989 Pontiac Lemans GSE.  IIRC with 120 speedo.  Redline
estimate would have been about 115 mph.

Then a 1989 Civic.  IIRC a 100 speedo.  Estimated redline around 110.

Then a 1999 F**d Ranger, 100 speedo.  It would have redlined past the
speedo limit.

Current vehicle: 2004 Jeep Wrangler, 120 speedo.  It does 60 at 2500
rpm and 75 at 3000.  Estimated redline about 120, but I haven't pushed
it past 90 (80's about as fast as is comfortable in it).

The Vettes got around the limit.  My '86 Vette has an eletronic
"gauge" that slopes up to 85, but the digital readout goes up to
whatever the car will go.

My parents' 1984 Pontiac 6000 LE, the world's greatest piece of sh.t if
there ever was one*, had a horizontal (i.e., not circular) 85-mph
speedometer in it. As others have mentioned elsewhere in this thread, it
likewise had the small circled 55 sandwiched in between the much larger
50 and 60 indications.

My father also had two company cars whose dashboards I can reasonably
recall back in those days. Both his 1986 and 1990 Ford Tempo GLs had
circular 85-mph speedos. For some reason, I'm drawing a blank on the
1993 Tempo he had after those two, but I think that the 1996 Ford
Contour they gave him next had a higher-than-85 speedo.

I'm too young to recall the dash of the 1982 Dodge Aries he was assigned
immediately before those Tempos -- all I can remember about that car was
that he let an A/C drain hose blockage remain way too long, causing
puddling on the passenger-side floor.

* You really want to hear the stories of how big a piece of sh.t the
Pontiac was? E-mail me.

My Current Vehicles: 78 Thunderbird - 85MPH Circular, 95 Cherokee -
85MPH Circular, 07 Compass - 120MPH Circular
Past Vehicles I remember: 91 Town Car - 85MPH Horizontal, 79 and 87
Mustang - 85MPH Circular, 84 Caprice - 85MPH Horizontal.

I still notice several NEW vehicles with 85MPH speedo's, but they do
appear to be a dying breed.

Why not just be a safe driver and cover the speedo with a piece of
cardboard and select your speed by fitting in with the other traffic?
(I'm a retired safety officer and do a continuous "risk assessent" as
the conditions change.)