Turbo Lag.

  • Thread starter KVelocity
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Is it finally time PD implements this? I mean if Gran Turismo is the real driving simulator it claims to be wouldn't it be only right to implement this?

Only if they provide the option to purchase an anti-lag kit, so that it will give me all the power, all of the time! >:0)
 
Indeed, and thanks, but not to drag this out unnecessarily, I was trying to ascertain whether you use the same distinction between this "hole" (being below the boost threshold) and the true lag / delay in building boost above the boost threshold (i.e. in throttle transitions).

Purely because it seems GT accounts for boost threshold in the torque curves, but not for lag itself.
Well, if you drive in the....ehm....I think it's the cockpit view, then you should see a graphic which shows the turbo boost. Now, if you play around with the throttle you see that there's at least visually a certain lag. Do this while driving in the highest gear.
I'm not sure if it's only visually or even affects the performance, I just can't really feel it, probably because it goes to full boost way too quickly.
 
Well, if you drive in the....ehm....I think it's the cockpit view, then you should see a graphic which shows the turbo boost. Now, if you play around with the throttle you see that there's at least visually a certain lag. Do this while driving in the highest gear.
I'm not sure if it's only visually or even affects the performance, I just can't really feel it, probably because it goes to full boost way too quickly.

Yeah, the boost gauge does seem to move very quickly, and although my butt-o-meter is disconnected from the experience, it definitely doesn't feel like there's any appreciable lag to me either. In earlier games that wasn't the case, certainly in GT2 there was considerable lag - but then the boost thresholds were often higher, too, so it's probably more indicative of the higher tuning levels allowed in that game.

So, I guess the problem is the "sensible" tuning that PD has introduced (and whitewashed turbo characteristics across all cars, regardless of year of manufacture etc.). I think a good compromise would be to accelerate drivetrain / engine wear with successively extreme tuning, and maybe allow race fuel (or some other such detonation prevention "device"), too, to make extreme power more of a compromise than a no-brainer.
 
I might sound a bit stupid here but does the Suzuki Escudo in GT5 have a very high boost threshold, or lots of turbo lag?
 
I haven't driven the Escudo too much, but I feel it's a high boost threshold ...

Same with the Ferrari F40, Tommy Kaira ZZII and a few others (like a high-rpm turbo on a Samba Bus :crazy:)
 
I might sound a bit stupid here but does the Suzuki Escudo in GT5 have a very high boost threshold, or lots of turbo lag?

Nothing has lag in GT5. Every turbo car in GT5 acts like it's NA.

In GT5 this is what happens:

Turbine responds instantly to throttle and achieves max speed/boost for a given RPM instantly. To get around this, all you need to do it place transmission gears close enough so that you're basically always in the powerband. Once you do this the "lag" (it's not lag) disappears.

In reality, when you floored the pedal the turbo would lag in its response, and it would be especially noticeable around peak power. So the blue throttle bar displayed in GT5 would instantly fill up when you hit the gas, but the boost gauge would take a second or two to max out. That is turbo lag.

Summary,

GT5: Turbo reacts as quickly as the blue throttle bar, there is no turbo lag, there is only the power band. Powerband issues can be fixed with transmission. Boost gauge means nothing

Real life: Turbo lags behind throttle/engine, there is turbo lag, and playing with the transmission won't fix it. Boost gauge provides valuable performance information.


There is no turbo lag in this video - watch the boost gauge



No lag, coming out of corners after releasing the throttle is trivial. The boost gauge jump is tied to RPM which is wrong.
 
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Is it finally time PD implements this? I mean if Gran Turismo is the real driving simulator it claims to be wouldn't it be only right to implement this?
GT1 had turbo lag. Join us in 2012, will you?

Reading above I'm seeing this has changed into "the boost gauge is the determining factor".
It is not.

The boost gauge is a gimmick, not unlike the "G-Meter", or physical specifications, or many other things in GT5. The accurate reflector would be racing a high-rpm turbo car against itself, and short-shifting one 2K early. The lag is there, it just doesn't show on the gauge.
 
Reading above I'm seeing this has changed into "the boost gauge is the determining factor".
It's not. The power produced by the engine is tied directly to RPM, as if there is no turbo to spool up.

For whatever reason the boost gauge is not acting properly, either because it's showing the actual responsiveness of the turbo (which shows no lag), or because it doesn't really show anything at all as you suggest.
 
GT1 had turbo lag. Join us in 2012, will you?

Reading above I'm seeing this has changed into "the boost gauge is the determining factor".
It is not.

The boost gauge is a gimmick, not unlike the "G-Meter", or physical specifications, or many other things in GT5. The accurate reflector would be racing a high-rpm turbo car against itself, and short-shifting one 2K early. The lag is there, it just doesn't show on the gauge.

How is short shifting going to achieve anything else than reflecting the peaky powerband of a high RPM turbo?

Also, don't look at the boost gauge, look at the instant increase in speed.

If you took a real life F40 or XJ220, floored it at 5000 rpm, there would be a delay before the car "took off".
In GT5 you get full torque instantly, as long as you keep the car above boost threshold!
 
dr_slump
Drive an Option Stream Z

Btw, the cars in GT5 have way less power than the examples you just brought. If you think a, geez I don't like this example, 700hp supra should have the same turbo lag as a 1200hp one when this was only realised trough boost, then you're completely mistaken.

It always depends on how extreme an engine is tuned, and the most in GT5 are still decent (of course is it already very high).

No I think a 700 hp supra should lag less and make less power ,then a 1200 hp supra that has horrible lag but would kill a Bugatti in a straight line Irl.i kno gt5 cars have way less hp...they shouldn't
 
To be honest I haven't noticed anything obvious. I kinda think I get a little lag when I'm in anything with a V-TECH but, that's most likely waiting for the V-TECH to kick in. Believe me, you will notice it.
 
That's not lag, exactly. That's being at an operating point where the turbine isn't being pushed enough. You have to break a minimum pressure / throughput in order for a given turbine to "activate" and be able to drive the compressor and begin building boost. Once that starts to happen, you set off a chain reaction until friction slows things down / destroys everything or you crack open the wastegate to keep speeds under control. The time it takes to go from that initial state to the steady "on-boost" state is the lag.

For example, cruising at part throttle well in the "power band" will only be producing a small amount of boost, but if you suddenly open the throttle, the boost won't be there instantaneously. That chain reaction of exhaust pressure driving turbine, driving compressor, increasing cylinder pressure and hence exhaust pressure etc. needs to occur first. That is lag, the time it takes for the engine to get where it should be for the given inputs.

Driving the car off the turbine map (etc.), so to say, is not lag, in the same way that driving a very highly tuned NA engine off-cam is not lag. The engine just isn't making as much torque at that point, and never will no matter how long you wait.


That said, the lack of true lag in the game is, in my opinion, a combination of the relatively reserved turbo tuning in the game (low hp) and modern low-lag turbo-compressors. The power-band modeling is there, it's just not as extreme as it used to be (again, "sensible" tuning).



all the "technical" terms you have used for stuff may or may not be right im not sure and im not going to look it up,In NO WAY am i knocking on you but have you ever driven a car with a turbo on it big enough to lag?You can call it lag,turbo hole,hyper speed response time or whatever you want but i have had multiple cars IRL that put down 500+ hp to the wheels and 90% of them lagged more then any car in this game.I understand what you mean by lag is from the point a turbo is at the lowest rpm that it even spools enough air to add pressure to the point where it is fully spooled.In real life this is usually shown on a boost gauge at idle your gauge if you dont have a cheap one will show vacuum pressure or negative numbers as you drive if you accelerate slowly it will go from -10,-9,-8,7 ect to 0 from there until the max boost that turbo is set up to produce is turbo lag.I agree with that most of teh cars in the game are not producing enough power to really have lag from a turbo, but they should have both more power and lag more in the higher hp cars.
 
To be honest I haven't noticed anything obvious. I kinda think I get a little lag when I'm in anything with a V-TECH but, that's most likely waiting for the V-TECH to kick in. Believe me, you will notice it.

v-tec compared to turbo lag? wow....anyways I think most of the people here are mistaking a power band that makes alot of power at high rpms and not much in the lower rpms for turbo lag,which is what PD tried to do.Ive had multiple 500+hp forced induction cars 6cyls and 8's and they had more lag then 90% of the cars on this game.I have a notchback mustang with a 427ci lsx stroker and it lags more then a 600-700hp 2.0L srt4 neon on this game which it shouldnt.
 
greedygenius
v-tec compared to turbo lag? wow....anyways I think most of the people here are mistaking a power band that makes alot of power at high rpms and not much in the lower rpms for turbo lag,which is what PD tried to do.Ive had multiple 500+hp forced induction cars 6cyls and 8's and they had more lag then 90% of the cars on this game.I have a notchback mustang with a 427ci lsx stroker and it lags more then a 600-700hp 2.0L srt4 neon on this game which it shouldnt.

Negative my friend I think YOU are wrong!! I think the whole idea of the thread was because of the OBVIOUS power change that you notice when turbos kick in from turbo lag. The reason I made my comment which is about a TURBO powered car, is because these particular vehicles are some of the few that I have found that you do find this sensation of NOTICEABLE power that is not there from the initial press of the accelerator.
 
You don't necessarily have to have a high power, large turbo engine to experience large amounts of lag. Any car made in the days before electronic boost control and variable geometry nozzles (See: Chrysler Turbo-I K engines, 80's Saabs) would have plenty of it regardless of how much power they provided. That's why manufacturers went out of their way to come up with "oddball" systems to get around it (like turbine pre-spooling in the Porsche 930).
 
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Saab's are well known for having turbo lag older Porsche's were tagged with this stigma as well. I'm not sure if it has translated over to GT5 as far the Porsche.
 
I always thought there was some turbo lag. I just remember in past GTs at least, I prefer NA cars over turbo due to the simple fact that I felt some kind of lag on the Turbo'd cars.

Isn't one of the reason's why there is three different turbo kit levels (low, mid, high) is because of where the lag lies?

Also, if the Option Stream Z doesn't mean turbo lag, then I honestly don't know what it is. That thing has one of the worst acceleration of any car in the game.
 
Turbo "lag" as per proper definition is a delay in engine response only loosely proportional to rpm. In general the bigger the turbo(s) is, the higher the lag because it will take more time for it to spool up and generate boost.

What you're referring about is boost threshold. It's not a delay: no matter how much time you wait at, say, 3000 rpm: if the turbo is sized to start giving significant boost at 5000 rpm, there will never be much power there.
 
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