Why doesn't every car have a turbo?


#1

Ever since I found out what a turbo is, sometime in the '60s, I’ve wondered why every car didn’t have one. Doesn’t it deliver more power for the same weight, better mileage from the same fuel? Mazda has just replaced the 6 in the CX-9 with a turbo 4 that delivers the same power. http://www.nytimes.com/2016/06/17/automobiles/autoreviews/mazdas-cx-9-a-crossover-thats-a-treat-for-parents.html

Is it too expensive? Trouble-prone? Recent advances in jet engines capture more air, compress it, increase the power for weight, the same thing.


#2

It increases the cost, decreases the reliability. It probably decreases the MPG slightly, depending on how you drive.

I’d never buy a car with one. I drive conservatively, so the turbo will rarely kick in. So I would have to carry around the turbo with it’s added weight, added friction, added cost and decreased reliability for no reason.


#3

Even though the EPA mpgs test out better with a smaller turbo engine vs. a similar power, larger non-turbo, road testing often indicates the non-turbo gets better mpgs. The current Mazda 6 gets much better mpgs in Consumer Reports tests than the similar turbo-engine Fusion.

Some turbos (the new VW 1.8 l, for example) do very well.


#4

Turbos add weight, add complexity, add cost and increase power. IF you keep it off the boost as much as possible, the smaller engine will give you better fuel economy but be available if you need it.

I have owned 2 turbo cars 16 years apart, one is still with us at over 105K, the other left at 83K. One had turbo-lag you could measure with a calendar, the other has very minor lag, but its still there.

Technology has made it all better. Formula 1 cars have 1.6 liter V6 turbocharged engines approaching 50% efficiency with just the engine and more when hybrid energy recovery and boost is included. The current F1 cars set faster lap times than the 3.0 liter cars of a few years ago with half the fuel.


#5

Recent Car and Driver compared several turbos to non-turbos:


#6

“It increases the cost, decreases the reliability.”

+1
Turbos also usually mean that more expensive oil and/or more frequent oil changes are specified.

“Turbos add weight, add complexity, add cost and increase power. IF you keep it off the boost as much as possible, the smaller engine will give you better fuel economy but be available if you need it.”

The “IF factor” is all-important, IMHO.
For many folks, the temptation to feel the engine spool-up with that turbo boost will lead to more use of the turbo boost than is healthy for an engine.

I compare the addition of a turbocharger to the use of amphetamines.
Both have the potential to boost performance, but both also have the potential to drastically shorten the lifespan. Just because somebody can run faster or jump higher, or have slightly more endurance with the use of amphetamines, that doesn’t somehow make them healthy for a person, just as a turbocharger can make things…unhealthy…for an engine.

I know that I may not have the choice in the future, but for many years, my choice has been to pay the cost for a larger engine that has very good power when I need it, but that also tends to run at lower RPMs than a smaller turbo-boosted engine with the same power output.


#7

Good article @texases I went straight to the Camaro vs Mustang review. Lag is still an issue but this was with manual transmissions not downshifted. My 2 turbos were a manual and an automatic. The turbo works better with the automatic. Boot the throttle and the trans downshifts as the turbo spools up so lag is minimized.

Interesting truck test, too. Torque gave the win to the EcoBoost model, but that performance had a price in 1 MPG lower economy. But the same around town economy, interesting.


#8

If there were no EPA gas mileage standards that are ever tightening, we would have far fewer turbos. It’s both cheaper and easier to build a slightly larger engine without a turbo. High performance cars have them to get extra performance. That’s a different story.

Hyundai has stopped putting 6 cylinder engines in their smaller and mid size cars and will have turbo boosted 4 cylinder engines to get the acceptable performance. There is an overall gain in fuel mileage.

So, why don’t all cars have turbos? Because car makers would rather not offer them in normal cars, but will be forced to offer them more and more as fuel economy standards tighten in the future.


#9

Just to go out on a limb, I think the only reason folks are going to the 4 banger turbo is to meet EPA requirements. Otherwise a V6 makes much more sense. The tail wagging the dog once again. Expense, reliability, maintenance, repair costs, but you can squeeze a few more MPGs.


#10

Regulatory compliance is job one. So manufacturers are moving toward smaller engines and tying to get acceptable performance from them. At added cost and reduced reliability.

Send your letters of thanks to 1600 Pennsylvania Avenue, Washington DC.


#11

Turbo’s have improved in both service life and reduced turbo lag. How the turbo is tuned makes a huge difference. In past years turbo’s were on racing and performance cars and the boost pressure’s were very high. A turbo in a more sedate family car uses reduced boost pressures and are designed to add boost at much lower rpm’s.

Basically a turbo could be on every motor. Yet, in the US there is still a bias to larger displacement motors for more torque, that’s what drivers are used to and they want the surge of power right away.

A small turbo motor that is using turbo boost much of the time will use as much or more fuel that and a larger motor without a turbo. Proper sizing of the motor, the transmission, and final drive ratios are also be factors in the final mpg number.

Some folks buy a turbo and expect great mpg, but they get deep into the gas a lot. When you use a lot of power for faster acceleration or higher speed cruising whether or not you have a turbo makes little difference.


#12

Have to agree with the general mindset here ,its rather interesting on the chevy Cruze ,the 1.4 and 1.8 have the same HP but the little guy generates more torque at speed ,however a turbo is good for high altitude life (like in the Rockies ) the Ford eco boost trucks kick butt at higher altitude ,but as the others said they add complexity and expense (turbo life is much better nowadays ) I always noticed on the older diesel engines the turbo charged caterpillars at constant speed and warmed up seem to be cleaner running,you have to appreciate how much air a turbo can pump ,we had a compressor with a 3306 engine and it was missing a plug in the intake manifold,it was amazing how much air the turbo could blow through that open hole(they even use turbo pumps to pump dry cement ,believe it or not) A turbo is a great device ,but like other things should be used wisely it has the effect of drastically increasing the virtual displacement of an engine .


#13

Why doesn’t every car have a turbo? I would hazard a guess that not every car needs one.

The Chevy Sonic hatchback with turbo I test drove was really neat.


#14

DO NOT SEND LETTERS TO 1600 PENNSYLVANIA AVE.!

Send them instead to the Obama Presidential LIbrary in Chicago when it opens. No sense in clogging the mailbox of the next president with bones you want to pick with the current president. There will be plenty of issues you may want to bring to the attention of the next president, no matter who He or She is.


#15

I agree with everyone else… The reason they arent or havent been on every vehicle in the past was expense primarily… You need to beef up almost every rotational part inside an engine to be able to handle a turbo…or rather to tame the Turbo.

Today we really do live in a “Golden Age” of engines and power… Many different things have all come together these days… Computer Controls, Lower Costs of mass production, more accurate machine processes… If there were ever a time for the Turbo to become commonplace (As it is rapidly becoming) That time is NOW…

But Yes to all of the above answers from the guys… Cost Complexity, Reliability…etc…these were all much larger back in the day…as a Turbo was semi Exotic… Just like anything…costs come down and all the technology of today helps everywhere else in Turbo Land… Good Times we are living in eh ?

Blackbird


#16

Also keep in mind the EU has CO2 emission regulations that are ever tightening. Since CO2 is a byproduct of all combustion, it is effectively the same as an MPG standard. Hence the turbo 4’s from VW/Audi, BMW and now Mercedes Benz. The turbo 4’s take the place of 6 cylinders in the BMW and Mercs.


#17

Because there are situations where linear power delivery is a must. Would you really want to find out what turbo lag feels like while going around a curve on a bike? I don’t


#18

A friend owned a 2-stroke Kawasaki in the early 70s. He didn’t think it had much giddyup until he downshifted one day and the bike ended up at about 5000 RPM when he let the clutch out. It took off from under him and it was all he could do to just hold on.


#19
Because there are situations where linear power delivery is a must

Electronics make that very possible. You can make the torque curve flatter and wider than most normally aspirated cars. Electrically boosted turbos are coming to eliminate lag entirely as are turbo and supercharging on the same engine.


#20
jtsanders A friend owned a 2-stroke Kawasaki in the early 70s. He didn't think it had much giddyup until he downshifted one day and the bike ended up at about 5000 RPM when he let the clutch out. It took off from under him and it was all he could do to just hold on.

I had one of those too. The engine just totally came alive at around 5000-5500 rpm and pulled strong up to around 7500 rpm and then it was over just as suddenly as it began. The joke was that these bikes could pass anything but a gas station.
But when it was in its power band, the throttling was actually quite linear. I had no problem riding long wheelies controlling the angle of the wheelie by the throttle opening.
It wasn’t that those bikes were uncontrollable, it was just that you had to be in the correct gear or some kid on a Honda 350 would leave you in his dust.