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Discussion Starter #1
Shorter, talk about what torque vectoring is and how the Q4 system works.

Hope it is enjoyable and informative, always open to comments and feedback, this mainly for fun and to give me an outlet for my geek love of car tech. My friends and family get tired of hearing it...


 

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oh, maybe you'll have snow in the next one.
good stuff - and although I take issue with the 60%, at least you have a logical explanation for why it is sometimes quoted.
 

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btw, your bit about one side on the shoulder - the wife had that with ice, she could see it coming, could feel the car doing something to adapt, but no nervousness, issues, slip etc. she was quite amazed and impressed.
 

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Discussion Starter #4
The "Official" Alfa US line is 60% front torque (from the website).

You feel, "something"(I think it is the lower front axle ratio comming into play, it is similar to how it feels when the driver downshifts and you are the passenger, but not the same), just nothing strange or bad, nothing to mess up your trajectory for instance.

Glad your wife is ok and happy with how the car handled it, obviously she can drive since most people would be to scared to notice anything in that situation.

No good snow yet this season....
 

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oh yeah, she's a very in touch with the controls/sensitive driver. always aware when something feels different, always tells/asks what's going on.
she quite enjoys the sq.
yeah, the official US hook, line and sinker - THEY should be explaining the different numbers, not leaving it for you to figure out/interpret why there are.
 

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Discussion Starter #6
It seems like ALfa US is primarily marketers and customer service, who know nothing more than hwat is written on the page in front of them...like most customer service and marketing people...

All the engineering is done it Italy, still waiting to hear back from them with my list of questions.....one of which is why the difference in the two numbers... they aren't contradictory (one being torque the other HP) but still...

However it makes sense, Italy says 50/50 engine power (HP), US is 60/40 torque split.
 

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Question, how can the front axle have a "lower" ratio than the rear? It can't If the front axle had a different ratio than the rear, when engaged it would case lots of binding and the system would grenade itself. On my cherokees, the final drive in the rear axle is the same ration as the front differential (which in this case is located IN the transmission)
 

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Discussion Starter #9
^ that covers it.

You are right about the Jeep systems, and the systems in pretty much every other car. In most cars the transfer case cannot handle "overslip" and will simply send all avalible power to the slipping wheel if using an "open" differential system, or bind and break if locked.

Alfa literally re-engineered mass-market AWD and improved it by designing a system capable of handling slip within the driveline. This also allowed them to play with the axle ratios creating an extremely unique system.

As far as I know Alfa is the ONLY manufacturer using different gearing front/rear. It really is a genius piece of engineering. ..and I bet the next generation of Jeeps starts using it, modified in one from or another.

Seriously, I am pretty positive Alfa is the first manufacturer to be giving us high-end WRC tech in a consumer vehicle. Separating torque and horsepower and delivering them to different axles is definitly high end rally racing tech.
(The system allowing slip to happen, combined with the differing gear ratios is what separates the Torque and HP, with torque - or twisting strength - going to the front, and horsepower - or speed - going to the rear. This type of thing has been happening in Rally cars for a long time. In consumer vehicles, it is unheard of in my experiance)

Gotta vent for a second though... all these professional reviewers and Alfa marketers have access to this same info, but none of them understand it well enough to explain it...

So I do it for free while looking for a new job kinda BS. (Currently work in the VFX industry freelance, feast or famine and I am starving right now)...back to sending out resumes/demo reels...
 

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Have a 1,200 foot driveway that is flat. Snowed 8 inches back in late November of this year. By morning the warmer temperatures had somewhat melted the snow down to a little over 3 inches. No plow had come through. My MY17 Giulia Sport Q4 handled very well with photos to prove it. Very satisfied and it matters since i work 5-6 days per week. Located in WV in the Shenandoah Valley close to DC metro.
 

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^ that covers it.

You are right about the Jeep systems, and the systems in pretty much every other car. In most cars the transfer case cannot handle "overslip" and will simply send all avalible power to the slipping wheel if using an "open" differential system, or bind and break if locked.

Alfa literally re-engineered mass-market AWD and improved it by designing a system capable of handling slip within the driveline. This also allowed them to play with the axle ratios creating an extremely unique system.

As far as I know Alfa is the ONLY manufacturer using different gearing front/rear. It really is a genius piece of engineering. ..and I bet the next generation of Jeeps starts using it, modified in one from or another.

Seriously, I am pretty positive Alfa is the first manufacturer to be giving us high-end WRC tech in a consumer vehicle. Separating torque and horsepower and delivering them to different axles is definitly high end rally racing tech.
(The system allowing slip to happen, combined with the differing gear ratios is what separates the Torque and HP, with torque - or twisting strength - going to the front, and horsepower - or speed - going to the rear. This type of thing has been happening in Rally cars for a long time. In consumer vehicles, it is unheard of in my experiance)

Gotta vent for a second though... all these professional reviewers and Alfa marketers have access to this same info, but none of them understand it well enough to explain it...

So I do it for free while looking for a new job kinda BS. (Currently work in the VFX industry freelance, feast or famine and I am starving right now)...back to sending out resumes/demo reels...
hey, just saw this, hope you found some more steady work in the interim!
 

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Only a hit. The q4 is made by Magna with some special specific from alfa.
Magnà is a leader in the market.
Alfa use a overspeed slip solution for from wheels when engaged
 

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Only a hit. The q4 is made by Magna with some special specific from alfa.
Magnà is a leader in the market.
Alfa use a overspeed slip solution for from wheels when engaged
thanks for sharing this.

If you dont mind me asking, where do you find “hard” technical info like this? Is there more white-paper type stuff published in Italian?

really wish we who parlo Italiano too poorly could get more than merely the (very cool) qv engine designer interview and the (also cool) translated “secrets of handling” PowerPoint :(
 

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Discussion Starter #14



Most of the hardware is provided by Magna International, with the Chassis Domain Control - which handles the traction control and AWD algorithms - provided by Magneti Marelli.

Both companies are top in thier fields, with Magna being the original designer and builder of the Mercedes G-Wagon, BMW SUV line, and even the original Audi TT (as well as the Jag electric SUV). Magneti Marelli is responsible for the traction control, active suspension and locking differential control algorithms utilized by teams in The World Rally Championship until the governing body made traction control and other high-tech things like launch control illegal, to stop a growing war where winning was more dependant on how much money was spent on electronics then the skill of the driver.

Easiest way to find this stuff is to search for industry releases, direct from the company.
 

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another way is having a direct contact with the giorgio team, my way.
the 4wd solution for alfa is really well setup, on dry, wet, snow and ice. an incredible and perfect mix of hardware e software solutions and configs
 

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Discussion Starter #16
Talk to them about the algorithms buried in "A" mode then.

I am positive they hid a version of WRC traction control and power managment algorithms deep in the "A" mode programing. At high speeds (60mph+) on extremely slippery surfaces like deep, slick mud and deep, loose sand it is unreal how the car handles.
 

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Discussion Starter #18 (Edited)
Good to see. Still cant find those things. Havent looked in a while though. Funny since video, that I've either been sick or swamped with work till now.

Notice the delay..the time it takes to move when the vehicle has reduced traction. Great example here actually since the wet/semi-frozen ground means..really, none of those tires had full traction.

Pay attention to the time it takes to get the car moving.

This is a RWD car that automatically switches to AWD, and juggles power around...beautifully well, but it doesn't happen instanainiously.

150ms or more depending on the complexity of the situation...which is faster than any competing system. Watch those same tests with a Land Rover, BMW, Ford or GM, whatever they don't move off faster...some of them dont move at all when you get down to 2 or 3 wheels without traction and one wheel with compromised traction.

What this means is......

None of these systems from any manufacturer is going to save you if you hit something like ice at 80mph...and considering the nannies take longer to respond than the AWD does..those systems can't save you either. The traction problems happen faster than the system can react. A very simple yet important concept.

Dont expect "systems" to keep you out of an accident regardless of speed or conditions.

Pay attention, always be in full control of the car, or ready to take over from the ACC/cruise control. Practice how to tap the brake pedal with enough pressure to turn off the ACC but not so much the brakes cause the car to slow. Either that or (better but harder) practice turning it off at the steering wheel, while steering, without looking.

Practice it till it becomes second nature and you can do it almost instictivly. Dont wait to respond thinking the car will do it.

The driver is the only REAL safety feature...the rest just backs him/her up. Good to know we basically have the best backup avalible.
 

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"Pay attention to the time it takes to get the car moving.'

5 star rating for those that don't want to sit through other vids for comparison.
the gentle transfer of power under power is one of the reasons the car is such a joy to drive.
not sure what mode they used for this - but it varies, as it should.
 
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