A tale of two turbos - Ford 2.3 vs Chevy 2.0

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I have previously posted on the 2017 Chevy Malibu with a 2.0 Turbo. I decided to look at its torque horsepower curve vs the torque horsepower of a 2023 Ford Explorer 2.3 Turbo which was also mentioned in a recent posting.

It’s a no brainer that the 2.3 has 50 more horsepower and more torque but somehow Chevy made the torque curve flat across 3,000 rpm, while Ford’s peaks and fades again. I’m not sure how that’s done, perhaps an adjustable scroll turbo?

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I bet they have more in the motor, but are pulling power to flatten the curve. Pretty simply to do: it probably pulls throttle to something less than 100%.
 
Some of it is the cylinder head ports/cams/exhaust manifold/turbo size choice. Also that the turbo was large enough to carry the torque curve flat way into 5000 rpm without dropping, "the hold" to 5000 rpm was all done with tuning and a large enough turbo. Then the rest and "most of the choice" is how it was "tuned" in the ECU with fuel mapping, ignition timing mapping, and cam phase mapping.
 
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However GM is doing it, it must be relatively simple. Doesn't look like the turbo uses electronic boost control or variable geometry. They can control torque via throttle plate plate position, timing, etc. etc.
 
I bet they have more in the motor, but are pulling power to flatten the curve. Pretty simply to do: it probably pulls throttle to something less than 100%.
Yep. The table-flat curve is simply engine management, pulling boost/fuel/timing to maintain a preset maximum level. Remove the nannies and the table will again become a curve similar to the Ford. It’s most likely done to keep the transmission alive.
 
I bet they have more in the motor, but are pulling power to flatten the curve. Pretty simply to do: it probably pulls throttle to something less than 100%.
This. The computer is limiting it there - that's why it’s so flat. Whether that’s for driveability, durability, or both, we will never know.
 
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Yep. The table-flat curve is simply engine management, pulling boost/fuel/timing to maintain a preset maximum level. Remove the nannies and the table will again become a peak. It’s most likely done to keep the transmission alive.
Very possible about driveline life. The trucks use “torque management”, although sometimes I think that’s to help with traction issues too. Limit off the line torque, less work for TC (traction control system) to deal with.

This is a bit of a SWAG on my part, but I think flat torque curves may appeal to some drivers. It lends itself to “smooth” power delivery, as opposed to a sudden (but short) peak. People can feel when the power lets off like that, but unless if they are timing 0-60 runs, it becomes wildly subjective. On a test drive, usually at some point, one gives it the beans. If the power suddenly comes on, then lets off, one can feel that—it won’t matter that the rest of the torque curve can be high, it’s the spike in g’s that is noticed.
 
Very possible about driveline life. The trucks use “torque management”, although sometimes I think that’s to help with traction issues too. Limit off the line torque, less work for TC (traction control system) to deal with.

This is a bit of a SWAG on my part, but I think flat torque curves may appeal to some drivers. It lends itself to “smooth” power delivery, as opposed to a sudden (but short) peak. People can feel when the power lets off like that, but unless if they are timing 0-60 runs, it becomes wildly subjective. On a test drive, usually at some point, one gives it the beans. If the power suddenly comes on, then lets off, one can feel that—it won’t matter that the rest of the torque curve can be high, it’s the spike in g’s that is noticed.
I can tell you that torque management and ECM can definitely neuter the feel of the engine. Going from stock to an 87 “tow” tune adds ~45HP/70TQ and makes the truck much more responsive. Plugging in the E30 tune (which forgoes towing but sheds a majority of torque management) the truck becomes an absolute beast (~10.6s 0-100 times).

The truck will bark the tires on shifts both to 2nd and 3rd, and the truck has the responsiveness of a much lighter vehicle. Sure, the ethanol tune picks up nearly 200HP at the wheels (max gain), but the torque surges from ~470 stock at the crank to over 600lb-ft at the tires. When combined with the fact that 5 Star takes a page out of the Raptor’s modes to keep the turbos spun up, lag is nearly eliminated, but mileage suffers from both ethanol content and the fact skip-shift is eliminated and the tune holds gears longer. But it’s worth every penny! 😉
 
I just found this from the GM Authority in posting #4.

View attachment 137727
I like the 2.0 LTG in my 17 Regal GS, it has a smooth steady pull when you nail it or merging on the highway, wondering what a tune would really do to this pocket rocket. :D

 
I like the 2.0 LTG in my 17 Regal GS, it has a smooth steady pull when you nail it or merging on the highway, wondering what a tune would really do to this pocket rocket. :D

Yeah the one in Malibu has been great. The twin scroll turbo certainly helps with performance. GM has a 1300 HP one. ZZP makes a ton of aftermarket stuff for them. I would like to mess with mine, but I drive it like 3 times a year. It is the wife's daily.
 
I like the 2.0 LTG in my 17 Regal GS, it has a smooth steady pull when you nail it or merging on the highway, wondering what a tune would really do to this pocket rocket. :D

It’s probably a blast. The other tiny four in this thread can easily top 400whp, so I’d imagine 325-350 for yours if the tranny would take it. 2018 Focus RS below:
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It’s probably a blast. The other tiny four in this thread can easily top 400whp, so I’d imagine 325-350 for yours if the tranny would take it. 2018 Focus RS below:
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It is a 6T70 GM rates it at 315 and 300 FT/lbs of toque. There is a 75 and 80 as well, not sure what the Buick has. I know the Malibu has the 70. Lots of guys running 400 WHP with the 70 and no issues. The 6T70 is also a Ford 6F50, 6F55 and 6F35 with some differences. It was co-developed starting in 02. I can't remember but I think the first use was 2007-2008? They use the thing in literally millions of cars. It is a pretty good unit. With no serviceable filter unless you crack the case. Fluid change gets 6 quarts out of a 9 quart capacity unit. Supposed to have a 250,000 mile service life.

Edit: Let me just say I am not running it up to 400 HP, I am not sure I would trust it. I am not even sure what I would do with a 400 HP Malibu.
 
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