Turbo lag and hybrid system simulation.

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3,725
Australia
Brisbane, Australia
Chameleon9000
Is there any evidence of either of these systems being properly (or at least partially) simulated in GTS? I'm interested to know for sure because I feel like these systems are pretty important to simulate in order to make the cars that use them feel more authentic and fun to drive.

Personally, some cars with large turbo chargers kind of feel like they "slingshot" out of the corners, but I don't know if its a placebo or not. :lol:
 
798
Canada
Vancouver
Nando_deBem
Is there any evidence of either of these systems being properly (or at least partially) simulated in GTS? I'm interested to know for sure because I feel like these systems are pretty important to simulate in order to make the cars that use them feel more authentic and fun to drive.

Personally, some cars with large turbo chargers kind of feel like they "slingshot" out of the corners, but I don't know if its a placebo or not. :lol:

You can check the turbo’s pressure on the hud.
For hybrid, some cars have it in the actual car’s hud, some don’t... like the LMP1 Porsche. It’s still modeled. You can feel it kicking in out of corners if you floor it, as the steering wheel will become lighter and you’ll understeer. You’ll also notice lack of power if you deplet your battery.
 
652
Italy
Under some Risotto
But Sport doesn't have an instrument or something like the one in GT6, right? I don't know why PD didn't include it (I don't drive the hybrids in the game that often :D)
 

GTV0819

(Banned)
6,084
Papua New Guinea
Papua New Guinea
Hi fellas. Let me dig up this thread if you don't mind.

Does turbo lag exists already in GT Sport? Was about to make a new thread regarding this one but good thing I have found this thread so I guess there's no point in creating a new one about it anymore.

I've read previous threads here before regarding turbo lag in the past games. Many players here say that it's not existent at all but some would point out that it did really exist. I just don't know if it's true. It is really a debatable topic, after all.

In GT5, some prime examples would be the Escudo and the Option Stream Z. If you would see the HP/Torque graph of these two cars in their respective settings, you would notice that both of them have a rather peaky powerband, translating to a very poor response from standstill even with a full throttle on. However, as the speed goes up comes the powerful surge from their turbocharged engines which would provide them godlike acceleration. Since the graph already speaks out for itself, I believe this is what they call boost threshold, although other people describe it as "turbo lag".

If I'm not mistaken, turbo lag happens when you are in the optimum RPM of the engine where the turbo would operate at its best, yet when you mash the throttle to the floor in that range, there's an hesitation for a few seconds before it would start to spool up. Am I correct?

I'm asking this because I don't have the game yet but I do have GT5/6 and in those games, I hardly feel that there is turbo lag. Maybe it's implemented properly already in GT Sport or maybe not. That's why I want to know and ask for your experience on this one.

BTW, the Ferrari F40 was also said to have turbo lag (in previous games) but probably that's boost threshold because of the combination of the tall gearing of its transmission and the turbocharged engine itself. Thanks
 
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1,374
United Kingdom
Oxford, UK
doc-shipman
You've described both elements of turbo lag. Turbo lag is the phenomenon of the turbo spooling before it can deliver power. This either happens because you are outside of the power band, or because you have hoofed the throttle in the power band, but under lift off conditions.

If you have partial throttle, in the rev band of peak boost, then the turbo is spooled and you won't experience turbo lag - at least not the levels that will be noticeably in anything remotely modern.

I haven't done any specific testing, but having driven older turbo-charged cars in GT Sport I can confirm that turbos - and turbo lag - are very much programmed in to each car, as they have been since the very early days of Gran Turismo (IIRC GT1 had turbo lag)
 

GTV0819

(Banned)
6,084
Papua New Guinea
Papua New Guinea
You've described both elements of turbo lag. Turbo lag is the phenomenon of the turbo spooling before it can deliver power. This either happens because you are outside of the power band, or because you have hoofed the throttle in the power band, but under lift off conditions.

If you have partial throttle, in the rev band of peak boost, then the turbo is spooled and you won't experience turbo lag - at least not the levels that will be noticeably in anything remotely modern.

I haven't done any specific testing, but having driven older turbo-charged cars in GT Sport I can confirm that turbos - and turbo lag - are very much programmed in to each car, as they have been since the very early days of Gran Turismo (IIRC GT1 had turbo lag)
What do you mean by both elements? Both boost threshold and turbo lag are different in terms of their behavior.

In GT5, essentially every car that comes with a turbo or slapped with it always has an instantaneous boost whenever you floor the throttle, meaning turbo lag is pretty much non-existant in-game. Basing on the turbo gauge in the display, it will fill up instantly base on the input of the throttle, even if it's below the threshold. For example, if you floor it halfway, then the gauge will also fill halfway and keeping it steady will not continuously fill it up until full. In other words, the gauge's bar is parallel to the throttle input, which shouldn't be the case at all.

Granting that the gauge is accurate (or maybe not), the way it fills up may differ for each turbocharged cars in the game and even if it does fill up fully at full throttle, some cars would still require a certain RPM for them to have good acceleration, which can be fixed by downshifting if they are below the engine's optimum powerband. The engine's power is sort of fixed to the RPM, which can be even seen in the power/torque graph. That is boost threshold.

Turbo lag is when you're already at operating speeds and you open the throttle, yet there's temporary hesitation before it kicks in. I have read that it acts that way regardless of what RPM you're currently in, even at the turbo engine's optimum range. This is what I understand and gathered about how turbo lag works.

So I'm guessing if PD already got this right in GT Sport, then I would be amazed about it.
 

FoRiZon

(Banned)
8,645
Singapore
Singapore
But Sport doesn't have an instrument or something like the one in GT6, right? I don't know why PD didn't include it (I don't drive the hybrids in the game that often :D)
Yes and it already feel weird.

It has a battery meter on the HUD on GT5 and GT6 but nada on GTSport?
 
1,374
United Kingdom
Oxford, UK
doc-shipman
What do you mean by both elements? Both boost threshold and turbo lag are different in terms of their behavior.

...

Turbo lag is when you're already at operating speeds and you open the throttle, yet there's temporary hesitation before it kicks in. I have read that it acts that way regardless of what RPM you're currently in, even at the turbo engine's optimum range. This is what I understand and gathered about how turbo lag works.

You have still described turbo lag both times, just in two different ways. They are both throttle-lag, caused by the turbo spooling up.

Turbo lag is a symptom, which can be caused by multiple things relating to a turbo spooling.

And, as said before, turbo lag has existed in most of the Gran Turismo games. I don't care what the little boost gauge on the HUD reads, I care about the physical outputs from a car running a turbo - these exist and thus turbo lag is modeled in Gran Turismo Sport.

Drive the rocket bunny BRZ drift car, it has turbo lag. Or the F-1500 as said above.
 

GTV0819

(Banned)
6,084
Papua New Guinea
Papua New Guinea
You have still described turbo lag both times, just in two different ways. They are both throttle-lag, caused by the turbo spooling up.

Turbo lag is a symptom, which can be caused by multiple things relating to a turbo spooling.

And, as said before, turbo lag has existed in most of the Gran Turismo games. I don't care what the little boost gauge on the HUD reads, I care about the physical outputs from a car running a turbo - these exist and thus turbo lag is modeled in Gran Turismo Sport.

Drive the rocket bunny BRZ drift car, it has turbo lag. Or the F-1500 as said above.
Oh I see. It sounds to me that you seem to try to deny my point by refusing to read what I'm trying to say and telling me that's it's still turbo lag. Or maybe because you simply have no idea about what is boost threshold at all. Well, I suppose that's fine. However.

And what the hell is throttle-lag anyway? Are you sure it even exists in-game? I'm not particular in GT Sport so have to really see it yet but like I said, boost seems to be instant in any turbocharged car in GT5/GT6 anyway when you nail the throttle so there would be essentially no lag at all since the turbo would spool up instantly. Go play and check if you want to. I seriously hope that turbocharged cars in GT Sport don't behave that way because it will be a poor simulation of the said thing once again.

Others also mention that GT1 seems to get it right better but imagine how many decades old that game is already.
 
210
United States
Massachusetts
The bigger the turbocharger, the longer it takes to build boost pressure.

In real life, engines run under constant vacuum. When any turbocharging/ supercharging (i.e "forced-induction") system is installed, it changes this vacuum into positive atmospheric pressure *under load* thus the term "boost" is used. Most ordinary cars run at -20 to -30 psi at idle. A stock vehicle tuned to the strict emissions standards of today, with a LPT (light pressure turbo) you might see a gain of +5 to +8psi (and 8 is high) at full throttle, when the turbo exceeds it's airflow, boost drops, gear changes. Repeat.

Again, the bigger the turbo, the longer the spool to change these pressures, thus "lagging" the time it would ordinarily take for air to reach the combustion chamber.

Without knowing exactly how engines are modeled in GT this (thread) is all speculation at best.

But imho yes, turbo lag is definitely present in GT Sport. And done quite well. A prime example is the Gran turismo formula car, the F-100 or whatever it's named.
It's probably not discernable to the average GTS driver because so few people have actually driven real life cars with huge spooling times.
 
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GTV0819

(Banned)
6,084
Papua New Guinea
Papua New Guinea
The bigger the turbocharger, the longer it takes to build boost pressure.

In real life engines run under a constant vacuum. When any turbocharging/ supercharging system is installed it changes this vacuum into positive atmospheric pressure *under load* thus the term "boost." Most ordinary cars run at idle at -20 to -30 psi. A stock vehicle tuned to strict emissions standards with an LPT (light pressure turbo) you might see a gain of +5 to +8psi at full throttle, when the turbo exceeds it's airflow, boost drops, gear changes. Repeat.

Again, the bigger the turbo, the longer the spool to change these pressures, thus "lagging" the time it would ordinarily take for air to reach the combustion chamber.

Without knowing exactly how engines are modeled in GT this (thread) is all speculation at best.
It would be really intriguing if PD would properly apply this in their racing games but sadly, that's still not the case at all. As far as I know, turbo lag only occurs once the engine is past the boost threshold, not below it. People though would still often confuse turbo lag for boost threshold, even during these days. It's getting tiresome to see them talk about something they don't really know about.
 

TonyJZX

(Banned)
3,945
Australia
Australia
I've been told that some hybrid systems do not need a button to deploy. Its just automatic with your accelerator.

I feel like many of us spent so much time driving the TS030 on GT6 that we are used to the way it should operate.
 
63
Honduras
Honduras
I've been told that some hybrid systems do not need a button to deploy. Its just automatic with your accelerator.

I feel like many of us spent so much time driving the TS030 on GT6 that we are used to the way it should operate.

I guess everyone knows it deploys automatically with acceleration but there should be a button so you could deploy it yourself:grumpy:
 
2,014
United States
Azle, Texas, USA
GTP_KinLM
KinLM
In regards to hybrid, yes.


In regards to turbo lag, no.

I drive an 07 STI as a daily driver. Not a “giant” turbo car, but still much more so than modern cars with economy oriented tiny turbos.

It also has the power plant from the Industrial Revol- I mean from the mid 1990s, despite being a “newer” car. So the power plant is a very good test bed for turbo lag and boost threshold.

In the STI, even if I’m at the dead peak RPM for the engine (somewhere around 5300 RPM) If I go instantly from 0-100% throttle, it takes nearly a full second for the turbo to go from full vacuum to the 19psi or so that it maxes out at.

This behavior is completely absent from GTSport as far as I can tell, and it has never been modeled. This is important to model because it’s something that happens whenever you’re on the throttle at all.

Even if you’re just giving 25% throttle, in a real turbo car, it takes a few moments for the boost to climb to whatever it’s peak is for said RPM sand throttle output (note: this can still be in vacuum, too. It’s not limited to only when your car is trying to reach high boost, or even boost pressure at all.)

In GTSport, turbo PSI is completely linear to throttle output. Whatever the “PSI” is preprogrammed to be at that RPM and throttle load, is what the game gives you instantly.

You can see how this would cause inaccuracies with how a car would drive in game, especially in a scenario where, say, you’re feathering the throttle in a long corner to try and help the car rotate (the final sector of Fuji is a good example of this.)

There is also “boost threshold” which some consider to be “turbo lag”. But the two really are not the same thing at all.

Boost threshold is modeled in GTSport as it is FAR simpler to model, it only takes a modification of the power curve.

This is when not enough exhaust gas is capable of flowing through the turbo at a given RPM/engine load to make any meaningful boost and power, so the engine feels “dead” for a while.

In my STI, this is the case from idle to ~3200 RPM or so.

This is “simulated” in GTSport and always has been. But it has nothing to do with accurate turbo simulation. It’s only messing around with the power band, to simulate this area where the turbo isn’t flowing enough air.

If somebody wants a good simulation of actual turbo lag, I would suggest older Forza games (I know Forza 4 modeled this relatively well, especially on older cars) and even DiRT Rally did an alright job (though many cars in Dirt Rally we’re equipped with Anti-Lag in real life, which seems to be modeled somewhat in game).

Both of these games model the time it takes for the turbo to actually spin up, for the exhaust gases to actually start putting work energy into the turbine and increasing the air that’s being sucked in.

If you don’t think this changes how you drive a car, go give one of these games a try. It’s a totally different experience to drive a violent RWD Big turbo car that actively feels like it wants to kill you whenever you start to lean on the gas pedal.

I hope that it is eventually modeled in GT. Even though it’s becoming much less of a factor on modern cars, it’s still present. And for older cars like the F1500 and 90’s turbo supercars, it completely changes the character of the car. Anybody on here who’s driven an older turbo car of any sort will definitely know what I’m on about and can back me up on everything above.
 

TonyJZX

(Banned)
3,945
Australia
Australia
I'm sure you guys in the EU and Asia have driven turbo diesel utes and vans... you know how those 2.0 to 3.0 turbo fours drive.

However these things can be fixed with ECU devices. I come from the other side where I driven Supras Skylines etc. and these are very slightly laggy out of the box but they only ran sub 10 psi boost?

With an ECU boost controller you can tune out the lag so that when you hit 2,500rpm it comes on too strong if anything. This is coming from someone who has also owned V8s.

Modern cars have all sorts of anti lag setups like variable geometry turbos and the like but generally on larger motors say 2.5-3.5 litres running say less than 14 psi boost the lag can be very miminal.

All bets off if you have a 2JZ Supra with a T78 single turbo etc.
 

GTV0819

(Banned)
6,084
Papua New Guinea
Papua New Guinea
In regards to hybrid, yes.


In regards to turbo lag, no.

I drive an 07 STI as a daily driver. Not a “giant” turbo car, but still much more so than modern cars with economy oriented tiny turbos.

It also has the power plant from the Industrial Revol- I mean from the mid 1990s, despite being a “newer” car. So the power plant is a very good test bed for turbo lag and boost threshold.

In the STI, even if I’m at the dead peak RPM for the engine (somewhere around 5300 RPM) If I go instantly from 0-100% throttle, it takes nearly a full second for the turbo to go from full vacuum to the 19psi or so that it maxes out at.

This behavior is completely absent from GTSport as far as I can tell, and it has never been modeled. This is important to model because it’s something that happens whenever you’re on the throttle at all.

Even if you’re just giving 25% throttle, in a real turbo car, it takes a few moments for the boost to climb to whatever it’s peak is for said RPM sand throttle output (note: this can still be in vacuum, too. It’s not limited to only when your car is trying to reach high boost, or even boost pressure at all.)

In GTSport, turbo PSI is completely linear to throttle output. Whatever the “PSI” is preprogrammed to be at that RPM and throttle load, is what the game gives you instantly.

You can see how this would cause inaccuracies with how a car would drive in game, especially in a scenario where, say, you’re feathering the throttle in a long corner to try and help the car rotate (the final sector of Fuji is a good example of this.)

There is also “boost threshold” which some consider to be “turbo lag”. But the two really are not the same thing at all.

Boost threshold is modeled in GTSport as it is FAR simpler to model, it only takes a modification of the power curve.

This is when not enough exhaust gas is capable of flowing through the turbo at a given RPM/engine load to make any meaningful boost and power, so the engine feels “dead” for a while.

In my STI, this is the case from idle to ~3200 RPM or so.

This is “simulated” in GTSport and always has been. But it has nothing to do with accurate turbo simulation. It’s only messing around with the power band, to simulate this area where the turbo isn’t flowing enough air.

If somebody wants a good simulation of actual turbo lag, I would suggest older Forza games (I know Forza 4 modeled this relatively well, especially on older cars) and even DiRT Rally did an alright job (though many cars in Dirt Rally we’re equipped with Anti-Lag in real life, which seems to be modeled somewhat in game).

Both of these games model the time it takes for the turbo to actually spin up, for the exhaust gases to actually start putting work energy into the turbine and increasing the air that’s being sucked in.

If you don’t think this changes how you drive a car, go give one of these games a try. It’s a totally different experience to drive a violent RWD Big turbo car that actively feels like it wants to kill you whenever you start to lean on the gas pedal.

I hope that it is eventually modeled in GT. Even though it’s becoming much less of a factor on modern cars, it’s still present. And for older cars like the F1500 and 90’s turbo supercars, it completely changes the character of the car. Anybody on here who’s driven an older turbo car of any sort will definitely know what I’m on about and can back me up on everything above.
Very well said, sir! I'm not surprised to learn that it's still not implemented in GT Sport until now but since I already know, I know what to expect now once I get to play the game.

And yes. Boost threshold is very common in these GT games. During gameplay, it can be fixed by more or less, staying in the optimal powerband of the car through using its gears, unlike turbo lag that can occur even if you're currently at the best range of its powerband. You would still experience a delay once you press the throttle and that can't be solved by down/upshifting at all. This feeling still isn't implemented in the gameplay until now.

I wonder how it will feel once PD models a turbodiesel powered car properly in the game.
 
9,771
Sweden
Sweden
eran0004
This is “simulated” in GTSport and always has been. But it has nothing to do with accurate turbo simulation. It’s only messing around with the power band, to simulate this area where the turbo isn’t flowing enough air.

Well, it does have something to do with accurate turbo simulation, but it’s not a complete model. Technically, any turbo simulation is only messing with the power band, the difference is how many variables you feed into the algorithm and how they contribute to the mess ;)
 
1,766
Spain
valencia
Donnced
I've been told that some hybrid systems do not need a button to deploy. Its just automatic with your accelerator.

I feel like many of us spent so much time driving the TS030 on GT6 that we are used to the way it should operate.

Well... Hybrid systems aren't very good simulated in GTS... Not in the F1 car and neither in the LMP1-H race cars...
The best game that try to simulate them properly in console is assetto corsa ..
And iracing in PC.

Examples :
Assetto corsa PS4:


Iracing :


In GTS you have not even manual DRS option.. The Mercedes open it automatically in every straight .

GTS is a great game, but focusing on "casual" players
 
697
Germany
Germany
As some people mentioned here already, i did experience turbo threshold, but i never actually experienced turbo lag

Threshold is especially noticeable on the cars that have big turbos and make a lot of boost, like F-1500T formula car for example: almost 4 bars of boost and it does take some time for turbo to kick in if you're driving from low RPM's (when accelerating after a low-speed sharp hairpin for example)

As for lag, i've never experienced lag neither in GT5, nor in GT Sport (those are the two GT games i play the most): boost gauge is fully tied to throttle input, as in if you run 50% throttle, you have 50% boost

I know that GT was never meant to be a full on simulation and always had somewhat casual note to it, but absence of such an prominent thing as turbo lag is sure confusing
 
798
Canada
Vancouver
Nando_deBem
I just would like to thank everybody here for talking all this stuff about turbos. I’m not really knowledgeable in cars. I tend to focus more on the “practical” side of it, like hot lapping and racing and trying to learn the cars reactions. This thread made me feel like I need to look more into the mechanics of it.
 

LeGeNd-1

Premium
6,872
Australia
Australia
GTP_LeGeNd-1
There is no turbo lag in GTS, only turbo threshold which is described by the power/torque curve. No matter where you are in the rev range, if you press the gas in a turbo car the turbo gauge always spools instantly to max.

Want to know something crazy? The first and only time turbo lag is properly modeled in Gran Turismo is GT1:



#Only90sKidsWillKnow
 

GTV0819

(Banned)
6,084
Papua New Guinea
Papua New Guinea
There is no turbo lag in GTS, only turbo threshold which is described by the power/torque curve. No matter where you are in the rev range, if you press the gas in a turbo car the turbo gauge always spools instantly to max.

Want to know something crazy? The first and only time turbo lag is properly modeled in Gran Turismo is GT1:



#Only90sKidsWillKnow

Lol, I never thought a Supra could go that fast in that old game and yeah, that's some enormous lag out there.