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2018 Stelvio Ti Sport Vesuvio Grey
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Who are y'all racing?

Just drive it how it wants to be driven - I noticed this a bit when new, and then I stopped flooring it off the line. This car likes a light, precise touch with everything, including the throttle. Brakes? Yep. Steering? Turn signals? Closing the hood? Yep yep yep.
The only time this is an issue for me is during heavy traffic around where I live. There are 3 lanes in both directions but the 3rd lane also serves as extra parking at night and mid day. So, often times I will find myself going over to the third lane with small openings between parked cars and then I need to gun it when the light turns green to get out in front of traffic before the 3rd lane is blocked again by another parked car(s).

You are right about needing a light touch though; especially the turn signals if you want to rely on the auto shut off.
 

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Figure out the timing on how to tip in the throttle just enough to have the wheels begin to spin.. after which point the gas can be mashed and the car launched.

Start slow, learn the timing, you'll get fast.

By start to spin I mean 1/4 rotation on the tires or less. Doesn't take much more then the weight of your toes on the pedal. Starting with very light pressure and quickly increasing it becomes as second nature as just slamming a foot down.
 

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Trade offs have always existed.
I have 2 older same era 500cc motorcycles, cable throttles with carbs. One has massive torque from idle, but signs off around 5000 rpm.
The other has next to nothing below 5000, but makes a heck of a lot more power from 7 to 12,000 rpm. Neither really responds well to just whacking the throttle fully open. For a few reasons.
As noted in 1st post, if you had a supercharger and a turbo ... then you'd stiil be wanting more boost or higher revs - and then longer engine life and better fuel economy.
 

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Any turbo car will have some lag from a stop. Nature of the beast. You can mitigate it by brake boosting, but who wants to do that all the time? And unless you're stop light racing every light why bother? If you want instant torque from a stop go get an EV. 😈
 

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There's been a lot of forum discussion about boost lag on the Stelvio 2.0 when the need arises for quick off the line acceleration.

Many of you have determined the Stelvio's boost lag is unacceptable and needs to be "fixed" via installing a GoPedal or some level of tune in an effort to make this characteristic disappear; all with little effect due to the basic engineering limitations of how quickly a turbo can spool up to provide a decent level of boost.

As I've written in other threads, virtually all manufacturers have figured out that boosted 2.0 liter engines are the sweet spot for power, MPGs, and emissions control, and even a taxation sweet spot in the EU where engine displacement determines what you pay.

0.5 liter per cylinder combustion chamber design has been pretty much perfected and works great for the most part. And yet, all boosted 2.0 engines seem to have the same issue with boost lag. (Yep, a couple manufacturers have done some creative things with one small diameter turbo and one large diameter turbo or a combo of supercharger and turbo in Volvo's case.)

Even the 340 HP Twin Turbo V-6 in my '17 Macan S had an initial throttle tip-in flat spot, very similar to what we see in the Stelvio. It is what it is with turbos, even when they're designed by the genius engineers at Porsche.

We need to recognize that automotive turbos spin at 200,000+ rpms at peak boost. I'm sure some engineer out there could tell us the linear relationship between turbo rpm and boost. Lets just recognize that at idle, that turbo impeller on your Stelvio is spinning very slowly and takes about a second or so to spool up.

Still, 122 cubic inches is 122 cubic inches and nothing will wake up that tiny little motor except for boost of some type, either from a turbo or supercharger. Of course, the problem with superchargers is they have a huge parasitic power cost that makes them unsuitable for small displacement engines. You'll see them on big V-8s though since there's enough inherent torque where it doesn't make much difference on Hellcats, etc.

So, what about the boost lag on the Stelvio?

I've been experimenting a bit with throttle tip-in technique and came to the conclusion that I can eliminate the lag by just doing some old school two foot driving; Something I learned back when I had crappy malaise era cars that didn't idle properly.

Left foot on the brake, right foot on the throttle, and bring up the RPMs just enough that you feel movement against brake pressure and let the brake go as you accelerate away. No lag whatsoever.

Using brake torque to bring up RPMs is nothing new or special by any means. Most of you have done similar things with other torque converter equipped cars. It doesn't have to be violent and you don't need a lot of RPMs to build a bit of boost and make the lag go away. It's just something that's really easy to do for those occasions when you have to go NOW.

I would encourage you to practice a bit and find that sweet spot of brake and throttle where you can do it smoothly.

I'd love to hear your results.
Porsche charges a lot of $$$ for installing what they call “launch control” in your car that pops a message in the dashboard that says that….its basically the same thing…..0 to 60 times decrease by a little bit…..half a second?
 

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Porsche charges a lot of $$$ for installing what they call “launch control” in your car that pops a message in the dashboard that says that….its basically the same thing…..0 to 60 times decrease by a little bit…..half a second?
I had launch control on my Audi Q5 TDI; that was how you would engage it ( i.e. brake boosting) but it would actually switch the TCU programming to much more aggressive. It was pretty damn cool.
 

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Discussion Starter · #34 ·
Porsche charges a lot of $$$ for installing what they call “launch control” in your car that pops a message in the dashboard that says that….its basically the same thing…..0 to 60 times decrease by a little bit…..half a second?
Every Macan has “sport mode” as standard equipment which is very similar to Dynamic mode on a Stelvio. “Sport Plus” was an option for Macan that allows for a higher RPM launch by changing programming on the PDK. In the first generation it improved 0-60 by maybe .2.

The new Macan has a much more aggressive launch in Sport + which allows 5200 RPMs at launch with the 4cyl. as per Car and Diver. It got into the 4.9 0-60 range after roll-out as per their recent test if I’m remembering correctly.

I believe the twin clutch PDK is capable of more radical operating parameters than the torque converter conventional ZF.
 

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Yup I think it went from 5.2 to 5.0 secs.....I have it in a Macan S but I think I have used it 3 or 4 times. I wonder how many "launches" the PDK can take......The Macan S PDK was not as beefier as the PDK in the Macan Turbo.
To drive in Sport Plus was not very comfortable since the RPM went all the way to 4000 before the PDK changed gears, the only thing nice about it was that the struts were firmer and the car lowered a little bit. But you could do that manually too.
 

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And if you keep the AS/S on...
As @Alfie said ...that makes things worse.

Definitely had a few times the engine shut off just as I was about to go from a stop sign and yeah......the delay caused by the restart is horrible. Turn the AS/S off.
Just get the automatic disabler. Simple install and only $60. Never have to turn it off again. First thing I purchased for mine and installed it the second day I had my car.
 

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I don't think it's turbo lag at all. It's a relatively small turbo that craps out at higher rpms. It's also a twin scroll turbo which are designed to reduce turbo lag. I believe it has to do with the TCU programming. Currently, I am in a Ford Mustang convertible as a loaner while my Stelvio is at the dealer for servicing and warranty work. There is essentially zero lag off the line on the Mustang. It also has a turbo 4 cylinder, albeit slightly larger at 2.3 liters.
 

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I don't think it's turbo lag at all. It's a relatively small turbo that craps out at higher rpms. It's also a twin scroll turbo which are designed to reduce turbo lag. I believe it has to do with the TCU programming. Currently, I am in a Ford Mustang convertible as a loaner while my Stelvio is at the dealer for servicing and warranty work. There is essentially zero lag off the line on the Mustang. It also has a turbo 4 cylinder, albeit slightly larger at 2.3 liters.
Absolutely

Its not turbo lag.

Even the naturally aspirated power is delayed for that .5 to 1 second on tip in.

Thats throttle lag.

Turbo lag on our cars is almost non existent. You can make 20psi at 2000rpm.
 
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