Torque Curve
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My assumption is yes, but I don't know if this is from a Dyno read out, or just engine testing.
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I have never seen a 3.6R torque in the real world that looks like the one shown. I am part of a tuning group and I have seen quite a few 3.6R that are tuned, even some with headers. They are not a flat, at least not at wheels they are not.
I am interested what virtual dynos from logging or a real world family Ascent on the dyno will show.
An all encompassing "get to know the Ascent" training. It was one of 50 or so slides on a power point presentation. I've since reached out to ask if it was on an actual dyno or how the testing was done but he didn't know.
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That's a reading directly from the flywheel, no doubt. From the flywheel thru the CVT is another story, may not be flat like that. I thought maybe since you're in the training, they may provide something verbally in regards to the actual performance at the wheel.
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No, I was in (effectively) the same training, just at a different location. 277 lb ft at 2,000 RPM on up, and flat, as opposed to the surge peak of others.
One isn't better than the other, its just a different kind of acceleration.
The advantage of the new Turbo engine is more torque (get up and go) while using less gas.
A flatter torque curve gives a more linear increase in power (smoother) as the revs increase. Remember, torque is per rev.
A peaky torque curve tends to bring on the power later and more abruptly as the revs increase. With the latter, need to get the revs up to peak torque to get the best acceleration. With CVTs, that will make for a louder and more droney engine.
Turbo engines allow for a flatter torque curve, as they generally have higher torque at lower rpms than their N/A counterparts (of similar HP).
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Yep, my guess, especially since the 3.6R curve s there for comparison.
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11,117 Posts
Glad you grabbed the shot! I lost the pic I had, and people kept telling me it wasn't flat from 2,000-4,800.I took this picture at a training a couple weeks ago and asked if I could share it. Then I completely forgot about it
Don't know why it is sidways
Here it is:
Doesn't get much flatter than that!!! :grin: :tango_face_wink:
I cleaned it up and rotated it.
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Actually, I was confused. If it's flat, then it's flat.
Since the Ascent has 8 gear ratios, here are the torque values (assumed no loss) if engine is @2000rpm+:
GEAR RATIO - Torque at gear @ gear speed (traveling speed)
Gear 1 (3.227) - 893ft-lbs @ 619rpm (12mph+)
Gear 2 (2.100) - 581ft-lbs @ 952rpm (18mph+)
Gear 3 (1.535) - 425ft-lbs @ 1303rpm (25mph+)
Gear 4 (1.191) - 329ft-lbs @ 1679rpm (32mph+)
Gear 5 (0.933) - 258ft-lbs @ 2143rpm (42mph+)
Gear 6 (0.749) - 207ft-lbs @ 2670rpm (52mph+)
Gear 7 (0.602) - 166ft-lbs @ 3322rpm (65mph+)
Gear 8 (0.467) - 129ft-lbs @ 4282rpm (84mph+)
values were calculated
The 3.6R would drop in ft-lbs as the RPM increases. For Ascent in 1st gear, you get 893ft-lbs of torque from 2000-4800rpm.
Since the Ascent has 8 gear ratios, here are the torque values (assumed no loss) if engine is @2000rpm+:
GEAR RATIO - Torque at gear @ gear speed (traveling speed)
Gear 1 (3.227) - 893ft-lbs @ 619rpm (12mph+)
Gear 2 (2.100) - 581ft-lbs @ 952rpm (18mph+)
Gear 3 (1.535) - 425ft-lbs @ 1303rpm (25mph+)
Gear 4 (1.191) - 329ft-lbs @ 1679rpm (32mph+)
Gear 5 (0.933) - 258ft-lbs @ 2143rpm (42mph+)
Gear 6 (0.749) - 207ft-lbs @ 2670rpm (52mph+)
Gear 7 (0.602) - 166ft-lbs @ 3322rpm (65mph+)
Gear 8 (0.467) - 129ft-lbs @ 4282rpm (84mph+)
values were calculated
The 3.6R would drop in ft-lbs as the RPM increases. For Ascent in 1st gear, you get 893ft-lbs of torque from 2000-4800rpm.
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Not you... I interact with a ton of people all over the place on many car (and computer and Star Trek and filming) related things, and I've been flat out told it's definitely not flat, and likely dies off very quickly.
Keep in mind the Ascent has no set gear ratios under numerous circumstances where torque would be needed. When I pushed hard uphill, it acted very much like a CVT, finding the engine's sweet spot and slowly and smoothly sliding the gearing in whatever direction was appropriate - no shift points. That makes a lot of sense for when the car is under load, whether due to hill climbing at full throttle or due to towing.
Or, to say that differently, I watched the rpm stay rather static while the gearing "slid" to accelerate the car.
I dunno how that would affect your calculations. I also have no idea what combinations of criteria would cause the CVT to act that way - I didn't have enough time to play that extensively. But, once I break mine in (well, once I get it and then break it in), I will report back.
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1,406 Posts
you know, there was the uphill towing limit of 45mph topic
Since the 1:1 ratio yield the 277ft-lbs (~45mph), I wonder if that's related. Because going about 50mph+ will yield lower torque
Since the 1:1 ratio yield the 277ft-lbs (~45mph), I wonder if that's related. Because going about 50mph+ will yield lower torque
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