2.0 turbo is king?


#1

I see the new bmw 5 series has a standard motor which is 4cyl turbo? I thought it was annoying when the infiniti g37 or is it Q50 had that motor available. its also in the caddy ats/xts and buick verano? and others I am sure. its all about gas mileage. sitting at a stoplight with a 4cyl uses less gas than a 3.8L whatever. even the Camaro and mustang are back with 4cyl motors. and the ford pickups with the ecoboost V6. I suppose it is a quick route to better mileage vs going hybrid for car makers.


#2

BMWs automatically turn their engines off at stoplights and restart them when you take your foot off the brake, so the engine size doesn’t matter there.

It is a mileage thing, but it mainly helps them fudge real world numbers in the EPA tests - normal drivers are not going to see the mileage they get on the tests because normal drivers are going to accelerate hard enough that the turbo spools up, stuffs more air in, and therefore more fuel will be burned.

We have ecoboost 4’s at work mixed in with the same vehicle running a non-turbo 4, and they all get about the same mileage.


#3

so you would expect the turbo motor cars to use more fuel since the drivers drive them harder? but you say the turbo and non-turbo cars average the same mileage. quite a few carmakers use the stop/start tech now. what does the a/c do when you stop at a 3-4 minute redlight?


#4

No, because it’s not the same 4-banger. The turbo cars have a smaller engine than the NA cars - 1.6L vs 2.5.

Pretty much everyone who drives our cars considers the accelerator pedal to be an on/off switch rather than a graduated control. They’re either on the brakes or they’re stomping the gas pedal to the floor. So we get the worst possible mileage because our drivers are idiots. And, fully wound out the turbo cars and NA cars get roughly the same mileage.

I’m sure the optional 2.0L turbo motor would see worse mileage than the 1.6, but we don’t have any of those.

Keeps blowing until the residual cooling is exhausted, then starts the engine.


#5

Some of the start-stop cars have electrically driven AC compressors, or so I’ve heard.

Turbo 4 technology has been around forever. BMW introduced it in the 1973 2002 model. GM in 1962. Saab from about '84. It is there to provide power when needed and MPG’s when not.

Chrysler cars had piles of them in the 80’s to provide adequate power with good MPG’s… My wife’s 16 year old Saab has a 2.3 liter turbo 4 and gets great mileage in real life with strong performance. Our 1985 2.3 turbo 4 Merkur, however couldn’t beat the highway MPG’s of my '84 5.7 liter Corvette but did better around town.


#6

For the F-150, the comparison between the 3.5L Ecoboost and the 5.0L N/A V8 is pretty close. the Ecoboost actually has more torque, but the real world MPG is almost dead equal with the EB getting slightly worse mileage when towing. You can have Eco or Boost, but not at the same time.


#7

the 73 bmw 2002 had a turbo 4? In the us? I know they use that crap in Europe. Remember magnum pi 308gts? They had a 2.0 turbo v8 at the same time to duck under the euro 2 liter tax bracket. Same block as 3.0 v8. U just bore out the cylinders and pop in the 3.0 Pistons. Now u have a turbo 3.0 v8.


#8

Yes, BMW had a turbo 4 in 1973 offered in the US market. Ferrari built a turbo 2.0 liter V8 in 1980 called a 208 GTB. The engine had the same stroke as the 308’s 3.0 liter but had smaller pistons, not larger.

Notice I mentioned a Oldsmobile turbo V8 from 1962. Chevy also turbocharged their air cooled Corvair motor in '65 and '66. Way earlier than the Europeans. Not successful, but offered.


#9

Excellent observation @cavell. I think you are spot on. So many cars, crossovers and other vehicles I tested were 2-liter turbos I did a spotlight on some of the ones that impressed me the most (Hyundai tops that list). I am also noticing that the automakers are all dramatically improving the drivability of the 2-liter turbos (we need an acronym, maybe 2LT). I spend a lot of time in a BMW with a 2-liter turbo that is now about 5 model years old. It has its faults. This past month I drove the BMW 530i and they all seemed to be gone! I found it powerful, linear, relatively quite (the direct injection makes a diesel-like racket), and it was very fuel efficient. The new trend is smaller than 2-liter engines. Honda’s new 1.5-liter turbo is fantastic. I’m driving a Civic this week that is rated a LARGE car by the EPA due to its interior space and it is a very quick car, under 6.5-seconds to sixty. My mileage over 150 miles of mixed driving is an amazing 41 MPG. This is a fully-loaded car for $27K. A Similarly sized Hyundai Ioniq Hybrid is $32K. I got 48 MPG in that car and it was not nearly as fun. Your idea that maybe this is the way to hold off on making everything a hybrid was exactly the angle I was thinking about for a story. You beat me to it!


#10

Gives owners the compromise of quick acceleration and more engine wear, or better mpg and a longer lasting engine, based on how they drive the car. Everybody gets their way with the 4 banger turbo design, makes the car easier to sell. The current F1 race cars use a similar design, 1.6 liter 4 banger turbo engine last I heard. The F1 engine has a hybrid electric-motor too I think. That’s probably up next.


#11

Current F1 has a 1.6 liter V6, not a 4. with hybrid energy recovery on the powertrain and the turbo. The V6 is a requirement as is the hybrid feature…

Back in the early 80’s the most powerful F1 engine was a 1.5 liter 4 cylinder from BMW estimated to produce over 1200 hp in qualifying and 1000 in race trim. The blocks came out of junkyard cars with at least 60,000 miles on them. Renault’s entry those years was a 1.5 liter 90 degree turbo V6 making a bit less hp… 900 or so.