Automatic Ecoboost Has More Acceleration Than Manual GT???

[Ardy]

From what I'm seeing here, an automatic Mustang Ecoboost has more MAX wheel torque than a manual GT. Not even considering that the ecoboost is lighter, it has greater peak acceleration.

Max acceleration (aka max wheel torque) for a car happens at peak torque in first gear.

Automatic Ecoboost: 350 x 4.696 x 3.15 = 5177 ft*lbs of torque at the wheels.

That's engine torque times first gear times rear axle.

Manual GT: 420 x 3.237 x 3.73 = 5071 ft*lbs of torque at the wheels.

I didn't even account for torque multiplication from the torque converter in the ecoboost. Or that the ecoboost is lighter. And I gave the ecoboost standard gears while I gave the GT performance pack gears.

Now this begs the question. How come the manual GT has more traction issues in first gear than the automatic ecoboost?

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Here's where I got the gear ratios from. Published by ford

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[ice445]

This is correct, but you have to look at the whole picture. Turbo cars excel at low end torque. The coyote is an NA engine with a more top end power band and doesn't make peak torque until 4500. But the ecoboost is already starting to fall off around 4500-5000RPM, just as the coyote is picking up steam. Peak torque and HP in the coyote is far higher so even though the EB will take it off the line by a little bit, it will still get passed assuming a decent driver.

The 10 speed also has a very aggressive 1st gear ratio because the computer can get into second pretty much right away, I'd wager the time the car spends in 1st gear is very low, so you'd have to do a time calculation to see which gear it would be in at the time the GT hits the end of its 1st gear.

 

[Ardy]

This is correct, but you have to look at the whole picture. Turbo cars excel at low end torque. The coyote is an NA engine with a more top end power band and doesn't make peak torque until 4500. But the ecoboost is already starting to fall off around 4500-5000RPM, just as the coyote is picking up steam. Peak torque and HP in the coyote is far higher so even though the EB will take it off the line by a little bit, it will still get passed assuming a decent driver.

The 10 speed also has a very aggressive 1st gear ratio because the computer can get into second pretty much right away, I'd wager the time the car spends in 1st gear is very low, so you'd have to do a time calculation to see which gear it would be in at the time the GT hits the end of its 1st gear.

Yes. That's correct.

But if you're talking just talking about which car can put you back in your seat more, the auto ecoboost has higher MAX acceleration.

Although the GT would still be more fun since it has higher jerk than the ecoboost because of turbo lag.

 

[ice445]

Yes. That's correct.

But if you're talking just talking about which car can put you back in your seat more, the auto ecoboost has higher MAX acceleration.

Although the GT would still be more fun since it has higher jerk than the ecoboost because of turbo lag.

Yep, you're right. It's better to compare it to a 2015-2017 GT because the gearing in the D4 revision of the MT-82 has been massively lengthened for some unknown reason, probably fuel economy to offset the extra horsepower. Or you can just change the gearing on the new cars to 4.09 final drive ratio since that's about the same as the 3.73 on the older cars. Or you can compare auto to auto, but the Ecoboost still has a very impressive ability to generate a big amount of torque in a very short amount of time. Definitely a great motor.

 

[bluebeastsrt]

I’ve read right on this forum. That the EB can lift the front tires off the ground at “part throttle”.

 

[shogun32]

Help me sleep!!!

how about not wigging out over something that is irrelevant?

 

[WildHorse]

Help me sleep!!!

Explain

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.

 

[Elp_jc]

Well, the stupid table says 'Getrag', instread of Ford MT-82. Hopefully the figures are correct. Interesting GT350s have 1:00 until 5th (vs 4th). And all trannies basically same highest gear ratio (0.6xx).

 

[ice445]

Well, the stupid table says 'Getrag', instread of Ford MT-82. Hopefully the figures are correct. Interesting GT350s have 1:00 until 5th (vs 4th). And all trannies basically same highest gear ratio (0.6xx).

Well I mean, the MT-82 is a Getrag design, just with some in house changes.

 

[Ardy]

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.

Higher horsepower happens at higher revs and means you can increase gear ratio and manipulate engine torque to increase acceleration.

Peak acceleration is determined by engine torque, not horsepower.

It's Acceleration=(Torque/Wheel Radius)/Mass

Horsepower is not in the equation

Yes the 1000 whp 100 lbs-ft car will win. But not if you put the same gears on it as you did on the 100 whp 1000 lbs-ft. If you did, then the 100 whp 1000 lbs-ft will win.

Also, remember we're talking about MAX acceleration. Not racing.

 

[Ardy]

how about not wigging out over something that is irrelevant?

First off, it's not irrelevant at all.

Second, that was just for comedic purposes.

Reasons why it's not irrelevant: Having more wheel torque should make the ecoboost a better drift car since it can break traction and spin the wheel easier. At least in 1st gear. But it's not. Why?

I'm guessing due to jerk. An NA car can shock the wheel loose while a turbo car eases power to the wheels which causes weight transfer to the back and makes it harder to let the wheels loose.

Important you see.

 

[Ardy]

my MT82 GT raped a A10 ecoboost from a dig

I never said the GT will lose. I said the maximum force that it puts you back in your seat in greater in an automatic ecoboost than in a manual GT.

Well I didn't even "say". I "questioned" others to confirm whether my understanding is right.

 

[Ardy]

I’ve read right on this forum. That the EB can lift the front tires off the ground at “part throttle”.

LMAO.

I wonder how close it would get if you could somehow launch the auto at 5k without spinning and at full throttle.

 

[shogun32]

Having more wheel torque should make the ecoboost a better drift car since it can break traction and spin the wheel easier. At least in 1st gear. But it's not.

who says so? Also you're "freaking out" 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.

You posted in the 'General' section, not the 'drifting' section. If you want to spin the wheels use a harder compound tire, higher PSI, different spring/bar settings.

An NA car can shock the wheel loose while a turbo car eases power to the wheels

What are you going on about? An automatic transmission by definition has much reduced drive-line shock compared to dropping the clutch on a manual. It has nothing to do with turbo vs na aside from turbo cars frequently have a big surge in torque at low'ish RPM whereas NA don't and best torque occurs at higher RPMs relatively speaking.

Unless you like picking up pieces of drivetrain, the key to spinning wheels is to apply enough torque (or lighten the contact patch) to break adhesion. Maybe I'm not watching the right videos but generally speaking drifting guys aren't breaking tires loose from a standstill.

 

[ice445]

I never said the GT will lose. I said the maximum force that it puts you back in your seat in greater in an automatic ecoboost than in a manual GT.

Well I didn't even "say". I "questioned" others to confirm whether my understanding is right.

You still need to calculate time into the equation instead of just theoretical maximum wheel torques, that will give a better picture because then you can see the percentage of time that the ecoboost is making more maximum torque compared to the GT. If it's only doing it for like 1 second or only in first gear (which is extremely short) then it's not going to affect the butt dyno nearly as much.

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