re: Turbo lag and supe lag

[Jay Negrin <jmnegrin@domain.elided>]

Biba commented:

In #1065 Michael Smith makes a good case for the turbo vs a
supercharger.

Okay, a bit embarrassed to admit, but I've never driven a car with
either one. I suspect everything he says is undoubtedly correct. There
must be good reasons why most auto makers use turbos rather than
superchargers.

And now my two cents worth (if it really is worth that much...)

Turbo lag is well dcoumented.  The higher the boost the longer the lag
time, in conventional systems.

Conventional logic also says that superchargers don't have (turbo) lag,
as they are "always on".  Simply, more revs equals more bhp.

Wait a minute, says I.

I had the occasion to take an extended drive in a VW G-lader Corrado.
1800 cc's of supercharged "fury"; something like 158 bhp, if memory
serves.  Had something like lag, although not from waiting to build
boost, sort of.  I think that VW lowered the compression on the motor so
it would survive a boosted life-style.  Until the boost came on, I'm
guessing at about 2000 - 2500 rpm, it was life with a LOW compression
1800 cc 4-banger.  Can we spell aenemic?  Once on the boil, as our
friends who speak the Queen's English might say, all was pretty good in
the motor dep't.  Until then, the lights were barely on, and it seemed
that most folks weren't at home to answer the call anyway.

But wait, it gets better.  To better stand the rigors of a blown life in
the fast lane, the mfg most likely went the route of stouter rotating
motor parts, including pistons and con rods.  As a result, the redline
was a paltry 5800 rpm.  That means, to me, a rather compressed working
range for the motor.  Needless to say, I was not impressed with the
driveline.  The chassis was OK for a front driver, but that is another
matter entirely.

Needless to say, I am sure if I have the dynamics wrong, someone will
correct me.  But from where I sit, that is what I surmised.  Anyone??

I am not really a fan of either super charging or turbo charging,
although it is hard to argue with the relative benefits of each.  I'll
take my spirits normally aspirated, thank you very much.

76 Alfetta GT - normally aspirated, and proud of those 26 year-old
horses, or how ever many of them have survived to date
97 VW (yup) VR6 GTI
81 Yamahammer SR500 - THUMP !
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