Date: 25 Jan 2004 15:09:28 GMT From: Dave Hinz <davehinznopsamcop.net> Subject: Re: Ok, can somebody please tell me the advantages and disadvantages of turbo?
On Sun, 25 Jan 2004 05:37:03 GMT, Harvey White <madynnopsametcom.com> wrote: > On Sun, 25 Jan 2004 05:18:39 GMT, Peter <garbagenopsamsafe.com> wrote: >> >>What is the positives with turbo and are there any drawbacks? > > Positives, smaller engine needed, higher power output when turbo kicks > in. When turbo kicks in, fuel consumption goes up. Without turbo, > fuel consumption is much better. Yes - you get more power (and the correspondingly higher fuel consumption) when you're getting heavy on the "loud pedal", but when you're driving normally you continue to have the fuel efficiency of the small engine. > Disadvantages: lag in turbo power boost, since it is run from the > exhaust gasses (there are mechanisms to make this somewhat better). The recent generation of turbo that Saab uses has a "low mass" configuration so it spins up much more quickly than the turbos of the 1970's, but it's still noticable. I'm not sure it's _bad_, just that it's noticable. > Mechanical complexity, it's another piece of equipment. Car will need > more frequent oil changes, but that's only good maintenance anyway. > (not more frequent than 3000 miles). Turbo has a limited lifetime, > and will eventually require replacement. (yet another thing to > break). I'm not sure I agree with this statement. The turbos are robust; it's not a normal wear item that you have to plan to replace or anything. My '88 900 Turbo still had (has?) the original turbo in it, when I traded it in at 247,000 miles, and the only "unusual" thing I did was use synthetic oil throughout my ownership of the car. Hearing about a turbo failure in a saab isn't by any means a common thing, going by this group's history and so on. >>Since Saab seems to be the only manufacturer with turbos, the question >>is why? > > They're not. Mercedes has them, Subaru has had them, Volkswagen (I > think) might have had them. Mitsubishi, Ford, Mazda have had them > (Ford Probe GT, 1989 to about 1993 or so, GT model). Mitsubishi > Eclipse, mostly any GX, I think. Also, turbos are widely used in the diesel trucking industry, for pretty much the same reasons - better fuel efficiency and power. Dave Hinz