RE: The Displacement Conundrum

[Thi VanAusdal <tvanausdal@xxxxxxxxxxxxx>]

Scott hits it on the head.
 
> For the big 6 cylinder engines (M30?), I seem to recall that the
> displacement was slightly lower than the badge indicated, but I'm not
> positive.  So, the 533i, 633CSi, and 733i had 3.2 liter engines, & the
> 535i, 635CSi, and 735i had 3.4 liter engines.  However, they were
close
> enough to reality, so we'll let that go.  Or, I could be 
> wrong.  Oh, and the 745i?  It was a turbocharged 3.5 liter.

Yes, they were 3210 and 3430 cc, respectively.  The idea of the 745i
was that the turbo motor is taxed at 1.4x the displacement in some
countries, corresponding to the increase in power.  Thus 3.5t >>"4.5".

> With the E30, the ID was changed on the 4 cyl car to 318i.  
> But, the 325e
> had a 2.7 liter engine.  I'm not sure why.

Likewise, the 325e's 2.7 liter was 'detuned' by using a milder cam and
such and thus put out power like a 2.5 motor.  Ironically, it puts out
gobs of torque and can move the car (with realistic gearing like 3.25:1)
rather smartly.  Anyway, it was called a 325e (and the 528e was 525e in
Europe).  The 528e was NOT called 525e because it was introduced first
and the Americans had just suffered a badge decrease in '79 from 530
to 528; it was felt another drop to 525 was just too hard to sell.

Recent displacement increases without model badge changes are likely
for model recognition purposes.  Go figure.

> More recently the V8s received displacement increases, but the IDs
> didn't change.  The 530i engine displacement was increased 
> (to ???) but
> is still called a 530i.  I think.  But it isn't available new 
> any more in the U.S. 
> The 540i engine went to 5.4 liters.
> 
> The 4 cylinder E36 cars all got 1.9 liter engines a few years ago, but
> they're still called 318i, 318is and 318ti.

How about a FAQ, someone (else)?

 - thi v.

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