My First Audi from an STi... I have a question.
02-24-2019, 05:12 PM
#1
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My First Audi from an STi... I have a question.
Hi all,
I hope you all are having a wonderful Sunday evening. So I want to start by saying...wow...Audi has made a wonderful car, and I cant even begin to imagine an RS3. So I work for Subaru in sales, and have driven every year and power range of STi over the past 10 years and still own 2. A 1999 GC8 2-door coupe with 07 STi guts and 581 awhp. I built that car from the ground up over two years. I also have a 2005 STi my wife drives, her baby really, with 400 awhp, made with some bolt ons and a tune. This has been all I have ever known. So enter this 2016 S3, came in on trade, leasee, who bought the car after the lease ended just to find hes having a kid in a month...sells the car...I have been daily driving a 2008 STi, and it was tired, and broken, and I saw this S3...and I knew it was my next car...anyways...I have now driven that car for a week, it has 22k miles, and is mint, in and out. I dont think I will go back to a new STi...ever...
so here is my question, sometimes when I get on it in my new S3 from a dig or cornering, its back end wiggles, not uncontrollably, but I was wondering if this is a normal handling charecteristic of planting its power? My rear tires are a bit more worn than the fronts. Any experiences like mine?
thanks for reading!!
02-25-2019, 05:45 AM
#3
2019 RS3 ordered 1-5-2019
OP (Original Poster),
Not a clue on your question really other than maybe since it's a 2016 a New set of the Right-Tires, possibly.
Tires always make a HUGE difference in cars .............
Good-Luck & Enjoy,
Terry
Not a clue on your question really other than maybe since it's a 2016 a New set of the Right-Tires, possibly.
Tires always make a HUGE difference in cars .............
Good-Luck & Enjoy,
Terry
02-25-2019, 06:17 AM
#4
AudiWorld Super User
Mine does a bit of wiggle too, but not until I did a ton of mods to it. "that's how you know its working" Its just the rear diff shuffling the power as far as I know. Mine only does it on launch control with all 4 tires spinning a bit and it begins to hook up (Stage II, rear traction tweak and Lots of chassis/suspension mods). I've had a couple Soobs, and we liked them but not even close to the same class of car... Just remember, Subaru backwards is u-rab-us! (Just kidding).
Its just the rear diff shuffling the power as far as I know. Mine only does it on launch control with all 4 tires spinning a bit and it begins to hook up (Stage II, rear traction tweak and Lots of chassis/suspension mods). I've had a couple Soobs, and we liked them but not even close to the same class of car... Just remember, Subaru backwards is u-rab-us! (Just kidding).
02-25-2019, 07:58 AM
#5
REALLY nice color S3 ! Good wheels too. As to it's rear wiggle under hard acceleration-- It is surprising that you would have this in a straight line but it IS possible. Especially if traction control, stability control is on and applying braking to wheels where it senses slippage. Your S3 is a different type of AWD. The Haldex drive unit in front of the rear diff is engaged anytime the computers sense front wheel slippage or even hard acceleration. This in effect gives you up to 100% of torque available at the rear when the fronts are slipping. (the front and rear axles do not have a center differential and the Haldex clutches lock them together.) I guess this could make your car more sensitive to worn rear tires. At least in the wet. Hard to imagine breaking them loose in the dry though unless cornering also.
02-25-2019, 01:11 PM
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REALLY nice color S3 ! Good wheels too. As to it's rear wiggle under hard acceleration-- It is surprising that you would have this in a straight line but it IS possible. Especially if traction control, stability control is on and applying braking to wheels where it senses slippage. Your S3 is a different type of AWD. The Haldex drive unit in front of the rear diff is engaged anytime the computers sense front wheel slippage or even hard acceleration. This in effect gives you up to 100% of torque available at the rear when the fronts are slipping. (the front and rear axles do not have a center differential and the Haldex clutches lock them together.) I guess this could make your car more sensitive to worn rear tires. At least in the wet. Hard to imagine breaking them loose in the dry though unless cornering also.
02-26-2019, 12:21 PM
#7
There is a difference with MY 2016 and MY 2017+ S3 units. In the 2016 and later models every data point coming into the central ECU unit was looked at separately, but in the newer models, they are looked at together and then adjustments are made on the fly. For example, in a Haldex-based all-wheel-drive setup, no more than 50 percent of the torque can be sent to the rear wheels. However, Audi made changes to the Haldex system, and now the rear differential is capable of handling up to 100 percent of the power. This allows for far less understeer, much more aggressive handling, and some actual rear-end rotation. You're a car enthusiast - I would suggest test driving a MY 17+ to detect the changes.While the 2016 units are just fine...this little tidbit can make a huge difference. Enjoy the new S3! While Subaru's are great cars, they are vastly different from Audi's even though both have rally racing roots.
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02-26-2019, 12:58 PM
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There is a difference with MY 2016 and MY 2017+ S3 units. In the 2016 and later models every data point coming into the central ECU unit was looked at separately, but in the newer models, they are looked at together and then adjustments are made on the fly. For example, in a Haldex-based all-wheel-drive setup, no more than 50 percent of the torque can be sent to the rear wheels. However, Audi made changes to the Haldex system, and now the rear differential is capable of handling up to 100 percent of the power. This allows for far less understeer, much more aggressive handling, and some actual rear-end rotation. You're a car enthusiast - I would suggest test driving a MY 17+ to detect the changes.While the 2016 units are just fine...this little tidbit can make a huge difference. Enjoy the new S3! While Subaru's are great cars, they are vastly different from Audi's even though both have rally racing roots.
Last edited by ntstambo2; 02-26-2019 at 01:00 PM.
02-26-2019, 01:09 PM
#9
FWIW, EVERYBODY describes torque splits in percentages. That is appropriate for AWD vehicles that have a center differential because they can have different ratio spider gears or Torsen gears to the front and rear output shafts. Haldex is different though. The Haldex clutches lock the front and rear axles together. ALL the torque 100% is always AVAILABLE at the front axle and UP TO 100% is AVAILABLE at the rear,, What the ECU decides is how hard to engage the rear axle and WHEN. If traction is equal front and rear and no tires slip but acceleration is hard enough to lock the Haldex clutches then yes— That’s 50-50. If you round a sharp low speed corner accelerating hard and lift a front wheel in a Haldex car, power to the rear will not be reduced because there is no center differential. In longitudinal engine Audis like my S5 a spinning front tire WILL reduce power to the rear axle. That is the reason for rear biased torque splits.
It’s a different system but the end result is remarkably similar in result.
It’s a different system but the end result is remarkably similar in result.
Last edited by J. Patterson; 02-26-2019 at 05:43 PM.
02-26-2019, 02:32 PM
#10
AudiWorld Super User
FWIW, EVERYBODY describes torque splits in percentages. That is appropriate for AWD vehicles that have a center differential because they can have different ratio spider gears or Torsen gears to the front and rear output shafts. Haldex is different though. The Haldex clutches lock the front and rear axles together. ALL the torque 100% is always AVAILABLE at the front axle and UP TO 100% is AVAILABLE at the rear,, What the ECU decides is how hard to engage the rear axle and WHEN. If traction is equal front and rear and no tires slip but acceleration is hard enough to lock the Haldex clutches then yes— That’s 50-50. If you round a sharp low speed corner acellerating hard and lift a front wheel in a Haldex car, power to the rear will not be reduced because there is no center differential. In longitudinal engine Audis like my S5 a spinning front tire WILL reduce power to the rear axle. That is the reason for rear biased torque splits.
It’s a different system but the end result is remarkably similar in result.
It’s a different system but the end result is remarkably similar in result.