Why don't they put turbos on more vehicles?

[SteveSRT8]

Lots of us are wary of anything with excessive features/parts.

Despite the fact that turbos are now widely used there are still issues with them for many drivers. Some are just ignorant, but any time you add more mechanical complexity you are ratcheting your odds of failure upwards. Turbos add a lot of failure points, it's playing the odds for the long haul.

I built my first turbo'd car in the early 80's, a twin turbo Chevy. It ran quite reliably and made great power, but to this day I still like the smooth progressive swell of power from a properly tuned N/A engine.

But I would definitely consider a blown car that gave me the proper 'feel' as modern engine controls have added greatly to the appeal...

 

[greenjp]

Originally Posted By: y_p_w
Originally Posted By: greenjp
When I bought my Saab back in 2003 a turbo gas engine was a rarity of sorts, pretty much just Saab, Volvo, and some performance models from the likes of Subaru (nearly all diesels have been turbo for decades). Nowadays there's a turbo option for nearly every model. Saab was ahead of their time RIP.

jeff

Huh? There have been lots of turbos over the years in passenger cars. There were all the Diamond Star cars like the Mitsubishi Eclipse. A lot of Buicks had been turbocharged since the 1980s. There were the notorious Chrysler turbocharged cars of the 80s. Heck - I remember the Renault Fuego Turbo and the Chevy Sprint Turbo made by Suzuki. The Ford Thunderbird Turbo won several awards in the late 80s.

Or the craziest was maybe the GMC Syclone.
...
Saab was not necessarily ahead of its time. Nearly all other carmakers tried turbos in some form or another but often bailed on them. They just happened to stick with a technology that had inherent reliability issues until water cooling made it more reliable.

Key words in my post were "rarity of a sorts." Yes there were some turbo cars over the years, usually special performance models, but as you note they were for the most part given up on. Saab started using them in the 80s (I think, maybe a few in the 70s) and never stopped. Walk into a Saab dealership circa 2000 and every car was turbocharged, even the base models. That was a rarity. They understood the power & fuel economy benefits which in today's regulatory and fuel price environment are even more important. Now turbos are found in the Chevy Cruze, nearly every BMW, and offered in lieu of a V6 by some companies. Like I said, ahead of their time. Lot of good it did 'em!

The answer to the OP's question is "they already do."

jeff

 

[whip]

Lots of negative views about turbos. I wonder how the new Mustang being turbocharged is going to go over? Especially with the old school folks.

 

[d00df00d]

To make something clear:

Just adding a turbocharger does NOT make the engine more fuel efficient. What it does is allow a smaller engine to do the same job as a bigger one, and that's where most of the efficiency comes from (e.g. using a 2-liter turbocharged 4-cylinder instead of a 3-liter non-turbocharged 6-cylinder).

The only possible exception would be if the engine is so weak that you have to work it really hard just to get from A to B. In that case, adding a turbocharger might help fuel economy. But then again, so might a bigger engine.

 

[d00df00d]

Also: Not speaking for anyone else here, but my distaste for turbos has little to do with reliability. I just can't stand how turbocharged engines respond to the gas pedal.

 

[Mykl]

Originally Posted By: d00df00d
Also: Not speaking for anyone else here, but my distaste for turbos has little to do with reliability. I just can't stand how turbocharged engines respond to the gas pedal.


I think that's largely dependent on the car though. From what I've driven it seems like BMW is the best at making turbo engines that don't feel like you're stepping on a cushion of boost you get on the gas. I test drove a new Mini Cooper S a few years ago and it didn't feel turbocharged, it was so responsive that it just felt like a powerful engine.

On the other end of the scale you could always feel a touch of lag in the Subarus I've owned. But the stock turbos on those aren't exactly top shelf.

 

[threeputtpar]

After owning the A6 for 5+ years now, I don't think that I can daily drive a non-turbo car ever again. When I drive the Honda, it feels like it only has one malnourished hamster on the wheel running the car as compared to the Audi. The Honda finally gets some grunt around 4500rpms, but who drives that way on a daily basis?

And as for reliability, I have two turbos that I have to worry about. I stick to the 5k mile OCI with approved oil and they have 160k miles on them with no sign of impending doom. I've been running 15-16 psi for the last 15k miles, too. Stock is 9psi.

Audi/VW have been doing turbos since the mid 90s, IIRC, so I think they have it down pretty well that I don't have to worry about the repair bills.

 

[whip]

I guess I'm in the minority. I enjoy a vehicle with character. Things like turbo lag or a car with touchy handling make the cars unique. A car that does everything well, like a Toyota, is kind of boring.

 

[thr_wedge]

Originally Posted By: d00df00d
Also: Not speaking for anyone else here, but my distaste for turbos has little to do with reliability. I just can't stand how turbocharged engines respond to the gas pedal.


This is a little more car dependent. My 2005 Subaru LGT 2.5L Turbo was very responsive. My 2007 Mazda CX7 2.3L DI turbo was so peaky it was ridiculous.

Both had me living in constant fear of a blown turbo, sludge, etc. Premium fuel requirements. Mediocre to bad fuel econ.

When we replaced the CX7, NA and regular fuel were a must. Now we have a 5.4L v8 vehicle that weighs 2x the CX7 and our fuel econ city only dropped 2mpg.

 

[d00df00d]

Originally Posted By: Mykl
Originally Posted By: d00df00d
Also: Not speaking for anyone else here, but my distaste for turbos has little to do with reliability. I just can't stand how turbocharged engines respond to the gas pedal.


I think that's largely dependent on the car though. From what I've driven it seems like BMW is the best at making turbo engines that don't feel like you're stepping on a cushion of boost you get on the gas. I test drove a new Mini Cooper S a few years ago and it didn't feel turbocharged, it was so responsive that it just felt like a powerful engine.

The BMW N54 (twin-turbo inline-6) is by far the most responsive turbo engine I've ever experienced, and it was still a bit dull (in terms of throttle response) until high-ish RPMs. Everything else I've ever driven, including an R56 Mini Cooper S and the new N20 single-turbo I4 (e.g. in the current 328i), has been intolerable to me.

If it doesn't bother you, then more power to you. I actually slightly envy you, because having a taste this strict really hinders my enjoyment of a lot of very good cars.

 

[hattaresguy]

That's why BMW uses a couple smaller turbos vs a single larger one. They make the motor run more like a NA one.

Smaller turbo's are one solution, variable veins are another, and lastly modern motors are controlled by pretty sophisticated computers.

Back in the day you had to control boost and fuel with vacuum and adjusted for altitude with an ALDA on diesels. That stuff caused all kinds of problems modern cars just don't have.

 

[Quattro Pete]

Originally Posted By: d00df00d
The BMW N54 (twin-turbo inline-6) is by far the most responsive turbo engine I've ever experienced,

They now replaced it with N55 which is a twin-scroll single turbo. Have you had any experience with this one? Supposedly it's even more responsive...

Yet the N20 also has a single twin-scroll, which you found less responsive...

In any case, I'm personally not a turbo fan either.

 

[kschachn]

Plus it makes it far more complex and expensive. That's the other reason BMW does it.

That's the real reason they do a lot of what they do. Some German engineer sits down, surveys the situation and asks himself - "how can I make this as complex as possible?"

Then after they have outlined the basic system they all work together to make the fasteners and brackets as confusing as possible, always working in the most non-intuitive fashion.

Originally Posted By: hattaresguy
That's why BMW uses a couple smaller turbos vs a single larger one. They make the motor run more like a NA one.

 

[d00df00d]

Originally Posted By: hattaresguy
That's why BMW uses a couple smaller turbos vs a single larger one.

Not always. The N20 and N55 are single-turbo.

 

[ClutchDisc]

Originally Posted By: threeputtpar
The Honda finally gets some grunt around 4500rpms, but who drives that way on a daily basis?

That would be me.

 

[Wolf359]

Originally Posted By: whip
I guess I'm in the minority. I enjoy a vehicle with character. Things like turbo lag or a car with touchy handling make the cars unique. A car that does everything well, like a Toyota, is kind of boring.


Oh yeah, the lag was sorta interesting, if your RPMs were low and you need to bash the throttle, it can take a moment for it to kick in. If you were in the power band though, the turbo could chirp the tires in 2nd gear. Touchy handling was torque steer in a front wheel drive car, you had to really hold onto the wheel when punching it because it wouldn't steer straight otherwise. Was fun though, when you're in the power band, it feels really fast, the turbo 4 that I had felt faster than a V8 because the V8 had smoother acceleration, the turbo on the other hand, nothing much initially then bang, you're gone.

 

[hattaresguy]

Originally Posted By: kschachn
Plus it makes it far more complex and expensive. That's the other reason BMW does it.

That's the real reason they do a lot of what they do. Some German engineer sits down, surveys the situation and asks himself - "how can I make this as complex as possible?"

Then after they have outlined the basic system they all work together to make the fasteners and brackets as confusing as possible, always working in the most non-intuitive fashion.

Originally Posted By: hattaresguy
That's why BMW uses a couple smaller turbos vs a single larger one. They make the motor run more like a NA one.


Their is no reason that it should not be a reliable setup. Marine diesels especially Volvo have been doing it for years.

People want lots of power and they want it now, they don't like turbo lag. That's why they do it, also fuel is not free.

If fuel were free they would have just stuck with large displacement NA straight 6's.

 

[hattaresguy]

Originally Posted By: d00df00d
Originally Posted By: hattaresguy
That's why BMW uses a couple smaller turbos vs a single larger one.

Not always. The N20 and N55 are single-turbo.


I'm sure their power output isn't as linear as a dual setup, unless they use variable veins, or its just a low boost system.

Smaller turbo's take less exhaust pressure to spin so they start working sooner.

Lots of ways to get 300hp out of an I6, I prefer the old fashion way of boring it out and making it rev to the sky...but I'm old fashion and don't care about fuel burn in such a car.

 

[SteveSRT8]

Originally Posted By: d00df00d
Also: Not speaking for anyone else here, but my distaste for turbos has little to do with reliability. I just can't stand how turbocharged engines respond to the gas pedal.


Totally agreed. It would seem that this is an acquired taste.

I would point out that BMW is somewhat unique in that they somehow kept some normal throttle response in their turbo 4's and sixes, but their V8's can be felt surging and so forth even when your foot is still...

 

[dailydriver]

Originally Posted By: OVERKILL
Originally Posted By: bigjl
If you want to see hilarious 80s turbo fun.

Google Renault 5 GT Turbo, the fwd version not the rwd rally car.

From memory about 120bhp from a 1.4 engine.

Though some people put the bigger 1721cc lump in for 200bhp plus.

A Renault 5 weighs about as much as a paperbag. Think in the region of 7/800kgs or1500/1600 lbs.



The Ford RS200 Cosworth was apparently INSANE.


Yes, and the 2.2 Evolution rallycross versions (up to ~800 AWHP, and MUCH MUCH lighter than ANY Mitsu, or Scoobie) were just pure CHAOS!!