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Discussion Starter · #1 ·
I have always driven cars with a manual transmission, and so I am just now getting used to my new QV with the automatic transmission. Everything seems fine with the transmission, but compared to a manual the throttle response seems to lag when starting from a dead stop. Once it gets going the motor has loads of power, but it's just in the first few moments when the gas pedal is pressed that the response is sluggish. I tried all of the driving modes and the result is the same. Has anyone else noticed this with their QV? I am used to the instant throttle response that comes with a manual transmission, and I'm a little disappointed in comparison.

I don' think this is being caused by turbo lag. Instead, it seems like the computer is a little slow in responding when the gas pedal is pushed. My old car has a normally aspirated 3 liter engine with 220 HP, and it responds instantly when the gas pedal is pressed. (BTW, I noticed the same lag in throttle response with the Maserati Ghibli.)

I think there are companies that make after-market throttle boosters, so maybe something like that would improve the throttle response. Does anyone know if a booster is available yet for the QV?
 

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Interesting observation......

in a "automatic" transmission (like my PDK 911 CS) it is a bit different to launch the vehicle......

did you try holding the brake down with your left foot while using your right foot to bring the revs up to say 3000-4000 RPM and then let your left foot off the brake and squeeze the gas? I bet you get a much quicker throttle response..... just make sure you do it in an open, non-traffic area......
 

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Discussion Starter · #3 ·
Interesting observation......

in a "automatic" transmission (like my PDK 911 CS) it is a bit different to launch the vehicle......

did you try holding the brake down with your left foot while using your right foot to bring the revs up to say 3000-4000 RPM and then let your left foot off the brake and squeeze the gas? I bet you get a much quicker throttle response..... just make sure you do it in an open, non-traffic area......
I'll give it a try. But even if it works I would still prefer to have a more natural response without having to use both pedals at the same time. When I say "GO", I want it to go without any delay!
 

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What you describe sounds like turbo lag. I have a LR Evoque that does the same thing. Going over speed bumps is maddening, waiting for that turbo to kick in.
A turbo engine will never feel as responsive off the line as a NA one. Though minuscule, even my Bi-turbo McLaren 12C has some lag at very low revs.
Unfortunately, I suspect the solution is not as simple as a software update. Hope to be wrong. Any 2.0 owners experience the same thing? I haven't been able to test drive yet. Maybe next week.
 

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What you describe sounds like turbo lag. I have a LR Evoque that does the same thing. Going over speed bumps is maddening, waiting for that turbo to kick in.
A turbo engine will never feel as responsive off the line as a NA one. Though minuscule, even my Bi-turbo McLaren 12C has some lag at very low revs.
Unfortunately, I suspect the solution is not as simple as a software update. Hope to be wrong. Any 2.0 owners experience the same thing? I haven't been able to test drive yet. Maybe next week.
There are three factors at play here, they are issues with both Giulias, and almost every turbo car.

1. Throttle response. This is the rate and amount of movement the throttle plate(s) gives you for a given amount of pedal depression. This can be enhanced in the lower range of operation with either an ECU tune or a pedal box of some type.

2. Boost Threshold. This is often confused with turbo lag. This is the RPM below which the engine doesn't generate enough exhaust gas flow to spin the turbo fast enough to create meaningful amounts of boost. In other words, if your turbos won't spin up below 2500rpm, that's the boost threshold. This threshold can be slightly lowered with an ECU tune designed to address this, and power can be increased below this range with a tune, which minimizes the issue.

3. Turbo lag, this is the amount of time it takes the turbo to spin up from the time you pushed down on the throttle when at an RPM that's above the boost threshold. This really isn't much of a problem in any Italian car I have driven, and there isn't much you can do about it in practical terms.

Greg
 

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My experience is the same. A lag when starting from a standstill in all drive modes. Frustrating
I do not think it is turbo lag. I drove a VW Jetta GLI with 200 HP and a 6 speed manual. 120,000 miles. Absolutely no lag. Very responsive. And it is also a 2.0 liter turbo engine.


I believe the lag is somehow related to the transmission, not to the turbo, as manual turbo cars seem to be more responsive.
 

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Interesting observation......

in a "automatic" transmission (like my PDK 911 CS) it is a bit different to launch the vehicle......

did you try holding the brake down with your left foot while using your right foot to bring the revs up to say 3000-4000 RPM and then let your left foot off the brake and squeeze the gas? I bet you get a much quicker throttle response..... just make sure you do it in an open, non-traffic area......
I just about fell off the couch laughing.
 

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There are three factors at play here, they are issues with both Giulias, and almost every turbo car.

1. Throttle response. This is the rate and amount of movement the throttle plate(s) gives you for a given amount of pedal depression. This can be enhanced in the lower range of operation with either an ECU tune or a pedal box of some type.

2. Boost Threshold. This is often confused with turbo lag. This is the RPM below which the engine doesn't generate enough exhaust gas flow to spin the turbo fast enough to create meaningful amounts of boost. In other words, if your turbos won't spin up below 2500rpm, that's the boost threshold. This threshold can be slightly lowered with an ECU tune designed to address this, and power can be increased below this range with a tune, which minimizes the issue.

3. Turbo lag, this is the amount of time it takes the turbo to spin up from the time you pushed down on the throttle when at an RPM that's above the boost threshold. This really isn't much of a problem in any Italian car I have driven, and there isn't much you can do about it in practical terms.

Greg
I bet it's issue #1. Excited to see what you all come up with. I've been too occupied with day to day ops to work on the fun stuff. Scheduled customers install of a eurodrive tuner/Ecu and intake on a 124 and v2/stage 2 ecu on a 4C next week though.
 

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Discussion Starter · #14 ·
I am very dissapointed with the throttle response in my QV. I do not think it would even be possible to lay rubber from a dead stop with the engine starting from idle. Launching the car would probably be a lot more satisfying with a manual transmission.

It's just ridiculous that I have a 505 HP motor and I can't even execute a "jack rabbit start" on a green light. I purchased a Go Pedal and I'm hoping that it will fix the problem. But I'm skeptical that it's going to work.

Another way to describe the throttle delay would be to compare it to the start button. When you push the start button there is a delay before the engine actually starts, and similarly when you push the gas pedal from a dead stop with the engine at idle, there is a delay before the engine actually starts to accelerate.
 

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A lot of the "Lag" is due to the traction control system stepping in even in Race mode, the system is not completely off in lower gear scenarios. I notice a small amount of wheel spin in 1st gear and in 2nd gear the car will step out and leave two nice little "foot prints" in the pavement. We have seen this when playing with certain parameters of the ECU.
 
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Discussion Starter · #16 ·
A lot of the "Lag" is due to the traction control system stepping in even in Race mode, the system is not completely off in lower gear scenarios. I notice a small amount of wheel spin in 1st gear and in 2nd gear the car will step out and leave two nice little "foot prints" in the pavement. We have seen this when playing with certain parameters of the ECU.
I'm starting to think that there might be something with my engine control unit, because I do not notice any wheel spin when I launch the car from standing start. In race mode I did get the back end to go a little bit squirrelly, but that only happened after I had already gained some speed and was making a right-hand turn. It's the first moment when I step on the gas that the throttle seems to be very lackluster. After it's rolled a few feet forward it will take off really good.
 

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A lot of the "Lag" is due to the traction control system stepping in even in Race mode, the system is not completely off in lower gear scenarios. I notice a small amount of wheel spin in 1st gear and in 2nd gear the car will step out and leave two nice little "foot prints" in the pavement. We have seen this when playing with certain parameters of the ECU.

Nice to see a vendor working on this already. Thank you!

Question. Having two ECUs will complicates things a bit and will it force higher costs?
 

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Chris Harris made note of it in his 2016 review (although in rapid fire while speaking). He said something like, "The Alfa just does not get moving like other cars..."
 

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Still trying to understand if we are talking the Ti here or the Quad...


For the Quad after watching/reading countless reviews I have never heard anyone mention anything about lack of throttle response - Again this is for the Quad.


I was just re-watching the Top Gear and Grand Tour episodes and they are frying the tires from a stop in all scenarios without any mention of lag - anywhere in the RPM band.


Am I missing something?
 
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