[Vwdiesel] Turbo talks -- ( more qestions ) ????

[LBaird119 at aol.com]

In a message dated 1/29/2004 4:00:12 PM Pacific Standard Time, 
h_hagar at prcn.org writes:

> Does turbo charging shorten engine life ?.
> Answer --- resounding yes yes yes. Simple grocery store logic. So if you 
> bolt on a turbo using your NA engine --expect shorter life.

 From "Diesel Fundamentals, service, repair" page 124:
  However, on one four-stroke engine, brake (hp) was increased 37.5%
over the (NA) engine.  On another engine, the increase was 56%.  Such 
increase is largely due to: 1) More complete scavenging. 2) Adequate air
to support complete combustion. 3) Improved mechanical efficiency of the 
engine.  There is no appreciable increase in friction hp with the increase in 

output."

  Page 127: (on efficiency and power increase)
  It will be noted that at 2100 rpm of the (NA) engine, the hp is 240 hp, 
while
that of the supercharged engine is 320 hp.  When aftercooling is added 
brake hp is increased to nearly 380hp.
  Improvement in torque and fuel consumption per brake hp hour are also 
impressive.  At 2100 rpm fuel consumption for that particular engine (NA) 
was .425 lb/hp hour and the supercharger was .38.  Only a slight improvement
was attained by aftercooling.
  Torque improvement for this same engine was 675 for the (NA) engine, 
875 for the supercharged engine, and 1025 ft. lb. for the supercharged and 
aftercooled engine."

 1980 LA Times: (on Motor Trend/BAE cross country turbo Rabbit run)
"Volkswagen also said it questioned the wisdom of turbocharging the 
Rabbit because, a spokesman said, Volkswagen believes the turbo 
device puts an extra strain on the small diesel engine that might 
cause a variety of types of damage.
  BAE emphatically denied Volkswagen's contention.  BAE's president,
 Robert McClure, said five Rabbits equipped with the company's 
turbochargers have now logged 150,000 miles each with no appreciable 
extra engine wear."

  he goes on to say they offer replacemet warranty to cover costs that vw may 

refuse to cover.  (something not done much yet, at that time.)

  There's mention in another article about same or better wear 
characteristics 
likely due to the more even loading of the piston rings.  Something I read 
at Jake's, I believe said that the better scavenging and cooler combustion 
temperatures contribute to LONGER engine, or at least component life than 
in a NA engine.  Cooler rings, less soot buildup, less lugging.
  I've yet to read any article that contributes shorter engine life to 
turbocharging.
Lot's of hearsay that it does with NO examples cited but nothing tested or 
even printed.  The only example I've seen was a nearly holed piston.  Sure 
the turbo contributed to the severity of it IMO but the CAUSE was a bad 
injector.
     Loren