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Automatic Ecoboost Has More Acceleration Than Manual GT???

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Ardy

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An automatic transmission by definition has much reduced drive-line shock
Yeah that’s what I said too. I said the NA manual can shock the wheels.

It has nothing to do with turbo vs na
What can happen if you try to ease into the throttle when trying to drift. Understeer rather than oversteer. Because of weight transfer. X hp NA will do you much better than same X hp Turbo. Now this is my hypotheses, never actually got to drive two exact cars with exact hp one being turbo and one being NA.
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Ardy

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over a 2% difference based on theoretical numbers and further assuming the driver of the respective car is precisely surfing the RPM range that corresponds to the stated maximum torque. Have some perspective.
Yes I understand your point. I’m talking about the theory/physics.
 

Vlad Soare

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You should also keep in mind that:
1. The difference is quite small (107 ft*lbs is merely 2% of the total torque), so it's most probably impossible to feel.
2. That difference only exists for a very, very short time.
Also, a manual is faster to launch than an automatic, unless the automatic has some form of launch control (which in the Mustang it hasn't).
So overall I don't think the Ecoboost will ever feel like launching faster than a GT. But it will probably be very close, which for a 2.3 is really no small feat. The Ecoboost is one hell of an engine, no doubt about that.
 

shogun32

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What can happen if you try to ease into the throttle when trying to drift. Understeer rather than oversteer. Because of weight transfer.
Ahh no. Under vs Over is a matter of traction. Drive both cars at precisely the RPM range that corresponds to 350ft/lb of engine torque (assumes rest of drive line is identical and therefore wheel torque is also identical) and they will behave the same. You may need to ballast the cars to likewise get the weight balance to match up.

NA vs Turbo is irrelevant. And yes my EB feels faster off the line than my GT does. Part of that is weight of course but also I don't launch either car at 350ft/lb RPM ranges either. They are both stick. The A10 feels quite a bit more urgent. But I don't like autos.
 

Balr14

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Newtons 3rd law: my MT82 GT raped a A10 ecoboost from a dig. That's science. Anyways, which is faster: 100 whp 1000 lbs-ft or 1000 whp 100 lbs-ft? Same car, same gear ratios, same driver, same weather. Easy. Higher horsepower car will always win, no matter the torque.
Not true. If you don't have enough torque to overcome mass, you can't achieve adequate speed for horsepower to matter. Torque is why turbo diesel trucks run 10s.
 

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Balr14

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Peak Acceleration always occurs at peak power. End of story.
True. But, it may take far longer to achieve max acceleration without adequate torque to overcome mass. That's why speedsters on the salt flats need a push to get up to an adequate speed.
 

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That's why speedsters on the salt flats need a push to get up to an adequate speed.
They also run around a 2.50:1 ring and pinion, & powerglide transmissions, with the torque converter removed. That's why they need a push.
 

Idaho2018GTPremium

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Peak Acceleration always occurs at peak power. End of story.
No, nope, no sir. Peak acceleration occurs at peak engine torque in a given gear. Haven't I explained this to you multiple times before in other threads? The reason we stay in a given gear long enough to reach peak hp, and then wait to shift, is because the wheel torque with the gear multiplication is higher at the high rpm than the wheel torque at the next gear up. This is because the multiplication due to gearing is higher than the drop in corresponding torque in the engine at high rpms.

Look at this theoretical example for a fake car: Peak engine hp is 7000 rpm, peak torque occurs at 4000 rpm:

Engine produces 350 ft lbs at 7000 rpm, with 3:1 trans gearing and 3:1 rear diff. gearing = 3,150 ft-lbs at the rear wheels in 1st gear

450 ft-lbs at 4000 rpm with 3:1 trans. gearing and 3:1 rear diff. gearing = 4,050 ft-lbs at the rear wheels. This will accelerate the car quicker than 350 ft-lbs, even though the peak power is at 7k rpm.

Now why do we shift at engine speeds beyond peak torque? This is why: 450 ft lbs at 4000 rpm with 2:1 trans. gearing and 3:1 rear diff. gearing = 2,700 ft-lbs at the rear wheels in 2nd gear. Less torque at the rear wheels = less acceleration.

The only reason the car accelerates harder in 1st gear at 7000 rpm than in 2nd gear at 4000 rpm is because of the torque multiplication of the gearing. The gearing provides torque multiplication at a higher rate than the engine torque curve falls off, thus, we stay in gear as long as possible, until the engine falls flat, or we reach the redline.
 

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No, nope, no sir. Peak acceleration occurs at peak engine torque in a given gear.
It does not. Peak acceleration occurs at peak power. If your peak torque happens at 4k and your peak power at 7k you're saying you're not accelerating from 4-7k? Come on now.
 

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It does not. Peak acceleration occurs at peak power. If your peak torque happens at 4k and your peak power at 7k you're saying you're not accelerating from 4-7k? Come on now.
I feel like hes got alot of numbers and explains himself really well, but you are very good at say nuh uh. This is an equal fight. Ding Ding.
 

Balr14

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They also run around a 2.50:1 ring and pinion, & powerglide transmissions, with the torque converter removed. That's why they need a push.
So they have no torque, hence they can't move. My point is you need both horsepower and torque.
 

shogun32

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So they have no torque,
wait, what? Are you saying land speed racers have no torque? Have you looked at the kind of engines they run? They need a push because they are geared so freaking tall that they would fry the clutch on rollout slipping it and slipping it forever before they were up to minimum speed that the clutch could be engaged. Try launching a 2-stroke 125cc race bike some time. They replace the clutch plates all the damn time because to launch one of these things they have to put 9000 on the tach and keep it there while slipping the bajeezus out the clutch so the RPMs (and available torque) doesn't crash to nothing. LSR vehicles have a similar dynamic but it's an artifact of gearing and not lack of torque.
 

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My point is you need both horsepower and torque.
Yes, Your are 100% correct for ground vehicles where the power is transferred to wheels.
 

Idaho2018GTPremium

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It does not. Peak acceleration occurs at peak power. If your peak torque happens at 4k and your peak power at 7k you're saying you're not accelerating from 4-7k? Come on now.
No man, you're not listening or simply not comprehending what I am saying (probably the latter). Of course the car is accelerating as long as the velocity is changing. But the rate of change of acceleration, called "jerk", is changing, and it follows the engine torque curve, and is affected by friction and wind resistance. Jerk is actually decreasing as engine torque drops. In other words, the rate of acceleration reduces as engine torque reduces.

I gave you proof that acceleration coincides with engine torque by showing you some theoretical rear wheel torque numbers. On a flat surface, rear wheel torque is the only thing that increases the speed of the car. Rear wheel torque is a linear relationship with the engine torque curve; only rear wheel torque is amplified by the gearing by a constant ratio.

Where are your numbers to back up your claim that peak acceleration occurs at peak hp, rather than peak torque?
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