Super charged vs. standard engine?

I am considering a Mini-Cooper and wondering what the pros and cons are
regarding these two engine types. Of course I know the fundamental things,
like lower gas mileage, more horse power with the super charge engine. What
about maintenance, engine life, repairs, etc.,. I don't have any experience
to draw on so any technical advice would be appreciated.
-Larry

As with a turbocharged car that extra power isn't free. It does come
at the cost of much lower mpg and higher engine wear if you have to be
the first across the intersection all the time. But those
generalizations apply to a normally aspirated engine too. OTOH if you
drive like most other drivers and stay with the flow of traffic I don't
think you will notice a big difference in milage and added engine wear
will be negligible.

A supercharger, like a turbocharger will eventually wear out and have
to be replaced. But you can say that about several other automotive
accessories too. So if you need (or want) the extra power that comes
from a supercharger then go for it.

Both of my cars have turbochargers, and I find the the added power to
be very helpful at times. I would drive both the standard and
supercharged version of the Cooper and base a decision on what seems to
work the best for you and whether it is worth thre extra $$. The
supercharger probably comes as a part of a package, so you will be
getting (and paying for) several other goodies as well.

The Cooper is a very attractive car in either configuration imho.

Thanks for your insight. I gather from your remarks that having a super
charged engine does not add any significant maintenance factor or should I
say reliability problems over a standard engine.

I will test drive both versions when I get an opportunity but just wanted a
heads up from the technical group and not rely on dealer sales staff.
-Larry


in article , John S. at
wrote on 7/19/05 12:27 PM:

> As with a turbocharged car that extra power isn't free. It does come
> at the cost of much lower mpg and higher engine wear if you have to be
> the first across the intersection all the time. But those
> generalizations apply to a normally aspirated engine too. OTOH if you
> drive like most other drivers and stay with the flow of traffic I don't
> think you will notice a big difference in milage and added engine wear
> will be negligible.
>
> A supercharger, like a turbocharger will eventually wear out and have
> to be replaced. But you can say that about several other automotive
> accessories too. So if you need (or want) the extra power that comes
> from a supercharger then go for it.
>
> Both of my cars have turbochargers, and I find the the added power to
> be very helpful at times. I would drive both the standard and
> supercharged version of the Cooper and base a decision on what seems to
> work the best for you and whether it is worth thre extra $$. The
> supercharger probably comes as a part of a package, so you will be
> getting (and paying for) several other goodies as well.
>
> The Cooper is a very attractive car in either configuration imho.
>

larry g. olsen wrote:

> Thanks for your insight. I gather from your remarks that having a super
> charged engine does not add any significant maintenance factor or should I
> say reliability problems over a standard engine.

With any kind of forced induction, bearings going south are probably
the most common failure. They can go bad prematurely if they overheat
and/or there's oil contamination/wear/starvation.

Pay attention to engine oil. Oil lubricates and (partially) cools the
bearings. Regular changes using a high quality oil should reduce the
chance of oil related failure, such as blocked oil passages, corrosion,
abrasive, etc.

I believe Mini only recommends high performance synthetic oils.

Replacing a worn supercharger is probably less than rebuilding an
engine. Even so - most of the newer ones are supposed to be more
reliable than in years past; most newer superchargers are also water
cooled which reduces bearing overheating. Take good care of it with
regular oil changes, and it'll take good care of you.

> I will test drive both versions when I get an opportunity but just wanted a
> heads up from the technical group and not rely on dealer sales staff.
> -Larry

Have fun.

larry g. olsen wrote:
> Thanks for your insight. I gather from your remarks that having a super
> charged engine does not add any significant maintenance factor or should I
> say reliability problems over a standard engine.

You are welcome. Those Coopers just look like they would be a lot of
fun to drive. I took an Austin Mini from London to Penzance and return
once, and it was a blast. The sensation of speed was amplified in that
tiny car that was just inches off the ground.

As long as you keep the maintenance up you should not have any
problems, but that goes for any engine.

A supercharger or turbocharger does essentially the same thing and both
result in more power for the car without changing the physical size of
the powerplant much. At one time both type of compressor had
reliability and performance problems, but those days are way behind
now. Both are reliable accessories.

As someone else noted the turbo runs in engine oil, so just be perform
regular oil changes and use synthetic. I've always changed oil every
3,000 to 3,500 miles no matter the car, and I've used synthetic in my
cars since 1996. I see the difference at 200,000 miles when the engine
still runs smoothly, gets good milage and when you look down into the
oil gallery there is no evidence of sludging. Frequent oil changes are
a cheap alternative to a prematurely wornout engine.

In article .com>,
says...

>As someone else noted the turbo runs in engine oil, so just be perform
>regular oil changes and use synthetic. I've always changed oil every
>3,000 to 3,500 miles no matter the car, and I've used synthetic in my
>cars since 1996. I see the difference at 200,000 miles when the engine
>still runs smoothly, gets good milage and when you look down into the
>oil gallery there is no evidence of sludging. Frequent oil changes are
>a cheap alternative to a prematurely wornout engine.

Synthetic is not needed to get long life out of a turbo. I had a Dodge Omni
GLH turbo. I sold the car with 153k miles on it without touching the turbo.
I used whatever brand name oil was on sale and changed it every 3k miles.
I also let the car idle for a minute or so before I shut it down. That the
core was water cooled also helped.
----------------
Alex

really enjoyed my 96 Pontiac Bonne V6
traded it at 120K miles and it was still running like new
very strong - lots of torque
admit that I sold it before the supercharger failed fearing the $2k repair
cost
I believe it was an Eaton s.c. in it.
Pretty neat, a low profile screw type air pump.

"John S." > wrote in message
ups.com...
> As with a turbocharged car that extra power isn't free. It does come
> at the cost of much lower mpg and higher engine wear if you have to be
> the first across the intersection all the time. But those
> generalizations apply to a normally aspirated engine too. OTOH if you
> drive like most other drivers and stay with the flow of traffic I don't
> think you will notice a big difference in milage and added engine wear
> will be negligible.
>
> A supercharger, like a turbocharger will eventually wear out and have
> to be replaced. But you can say that about several other automotive
> accessories too. So if you need (or want) the extra power that comes
> from a supercharger then go for it.
>
> Both of my cars have turbochargers, and I find the the added power to
> be very helpful at times. I would drive both the standard and
> supercharged version of the Cooper and base a decision on what seems to
> work the best for you and whether it is worth thre extra $$. The
> supercharger probably comes as a part of a package, so you will be
> getting (and paying for) several other goodies as well.
>
> The Cooper is a very attractive car in either configuration imho.
>

John S. wrote:
> As with a turbocharged car that extra power isn't free. It does come
> at the cost of much lower mpg and higher engine wear if you have to be
> the first across the intersection all the time. But those
> generalizations apply to a normally aspirated engine too. OTOH if you
> drive like most other drivers and stay with the flow of traffic I don't
> think you will notice a big difference in milage and added engine wear
> will be negligible.
>
>
A supercharged car can actually save a bit of gas in normal driving. An
engine is not efficient at low throttle settings. In fact, it would be
most efficient at wide open if it were not for power enrichment
programming to aid drivability.

If we have two engines, one with large displacement giving a certain
horsepower, and another that is smaller, but turbocharged, then in
normal driving at partial power- say ordinary street driving, the
turbocharged car is running at a higher percentage of throttle, and
hence a little more efficient.

This is the same rationale that makes hybrids so efficient. Use a small
engine and run it at a higher percentage of its power capability. Also,
especially in a series hybrid, the IC engine does not need power
enrichment because the electric motor does not create drivability problems.

Don Stauffer wrote:
> John S. wrote:
> > As with a turbocharged car that extra power isn't free. It does come
> > at the cost of much lower mpg and higher engine wear if you have to be
> > the first across the intersection all the time. But those
> > generalizations apply to a normally aspirated engine too. OTOH if you
> > drive like most other drivers and stay with the flow of traffic I don't
> > think you will notice a big difference in milage and added engine wear
> > will be negligible.
> >
> >
> A supercharged car can actually save a bit of gas in normal driving. An
> engine is not efficient at low throttle settings. In fact, it would be
> most efficient at wide open if it were not for power enrichment
> programming to aid drivability.

I thought a supercharger was demand based, i.e. not running at light
throttle openings

>
> If we have two engines, one with large displacement giving a certain
> horsepower, and another that is smaller, but turbocharged, then in
> normal driving at partial power- say ordinary street driving, the
> turbocharged car is running at a higher percentage of throttle, and
> hence a little more efficient.

Efficient as measured by mpg?

>
> This is the same rationale that makes hybrids so efficient. Use a small
> engine and run it at a higher percentage of its power capability. Also,
> especially in a series hybrid, the IC engine does not need power
> enrichment because the electric motor does not create drivability problems.

In article .com>,
says...

>I thought a supercharger was demand based, i.e. not running at light
>throttle openings

No, that more accurately describes a turbocharger. Until you get enough
exhaust gas flow, it is basically doing nothing. To get more exhaust gas
flow, you need to step on the throtle some more.

-----------------
Alex