Torque Physics (Turbo, VVTi, Vtec)
- Thread starter TayeezSA
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"In the Gran Turismo 6 STI, I couldn't really feel when the turbo spool or lag happened. Same goes for Vtec. Even when I slapped on turbos of different ranges I couldn't really tell the difference.
Is there anyway that this aspect can be improved upon? Maybe even working with companies like Borg Warner Turbochargers or Garrett to determine the behaviour of turbos and Honda on Vtec transition?"
@TayeezSA If they didn't have 10 different versions of the same make, maybe they can establish this by some clever programming. It is hard work.. and I'm not sure if they're up to it.
In all honestly, I do not even mind 20 - 50 cars in a proper sim, one which accurately simulates every performance and behavioral characteristic of the said car, including sounds.
Is there anyway that this aspect can be improved upon? Maybe even working with companies like Borg Warner Turbochargers or Garrett to determine the behaviour of turbos and Honda on Vtec transition?"
@TayeezSA If they didn't have 10 different versions of the same make, maybe they can establish this by some clever programming. It is hard work.. and I'm not sure if they're up to it.
In all honestly, I do not even mind 20 - 50 cars in a proper sim, one which accurately simulates every performance and behavioral characteristic of the said car, including sounds.
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- Tayeedz1
20 - 50 is oh so tiny. Though I said cars must be slashed, I didn't mean THAT much
I've noticed something actually. I looked at the vehicle stats for my experiment as said in my first post for bpth the real life and game's STI. When looking at the torque figures for the Blobeye STI , the RPM for when max torque is reached is exactly the same as in real life, ie when the turbo spools and you have that RPM surge and Turbo slam.I tried the Turbo experiment again in game and looked over some videos I had from 2012 of the real life STI. It's mostly sound and you see the tacho here and there but can be used. The Real Life car has a more noticeable torque feel as opposed to the game over the same rpm. I think @Speedster911 it shouldn't be difficult to program but rather modifying what's there in the game already. Pair that with the new sound and Bob's your Uncle.
By the way, for those that say this isn't a race affecting feature (Ello there @Tenacious D ), why is it that rally cars, and I'm speaking in real life terms here, have anti-lag? Even the GT cars with turbos have some form of Anti lag. Race affecting feature mate, plus it's more fun
I spoke to my mate as well again and he's happy that this question is getting some attention, thanks everybody! He says that Euro Truck Simulator has a great Torque Simulation. Something to learn from maybe?
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20 - 50 is oh so tiny. Though I said cars must be slashed, I didn't mean THAT much
I tried the Turbo experiment again in game and looked over some videos I had from 2012 of the real life STI. It's mostly sound and you see the tacho here and there but can be used. The Real Life car has a more noticeable torque feel as opposed to the game over the same rpm. I think @Speedster911 it shouldn't be difficult to program but rather modifying what's there in the game already. Pair that with the new sound and Bob's your Uncle.
By the way, for those that say this isn't a race affecting feature (Ello there @Tenacious D ), why is it that rally cars, and I'm speaking in real life terms here, have anti-lag? Even the GT cars with turbos have some form of Anti lag. Race affecting feature mate, plus it's more fun
I spoke to my mate as well again and he's happy that this question is getting some attention, thanks everybody! He says that Euro Truck Simulator has a great Torque Simulation. Something to learn from maybe?
Cutting down car count significantly will immediately bring in the goods - all that energy and resources can be redirected towards faithfully reproducing cars almost exactly to their real world specs. The year is 2014, PS4 is here.. if PD botches up again.. I'm just giving up on it entirely. I'm making peace with it and never looking back.
Remember the original NFS from the early 90s? That had less than 10 cars, and it was the most accurate sim at the time. Many games in the following years did not even come close to recreating handling and sound the way EA did back then.
Car count is one of the biggest mishaps and evils in the GT franchise. Cut down car count.. faithfully recreate performance handling and sound for each, then make more cars available. Any good developer, programmer and business owner would see the long term benefits.
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Turbo lag and boost threshold are two different things.
A torque curve extracted from a dyno pull will be almost representative of steady-state, so the boost level at all rpms at full throttle can be extracted from that same run.
Turbo lag is the time it takes from throttle application for the boost to build to the steady state value for that rpm.
You reduce that by reducing the mass moment of inertia of the turbo-compressor assembly, and its friction, as well as the total volume of the turbocompressor system. Generally that means smaller turbos lag less, especially with minimal plumbing.
The boost threshold is the steady-state rpm at which the engine just begins to build boost, i.e. manifold pressure exceeds atmospheric. That is determined by the turbo-compressor spec and engine size and tuning, and is all that is available to tweak in the game.
As for sound, the 97T is the only car that seems to model turbo lag; it's not in the physics, though. That strikes me as odd. It sounds a lot like a model I made, and tested in LFS; basically the exhaust gets a bit louder and there's a lot more flow noise, fading in gradually over about half a second as the "boost" builds.
The acoustics of any ducting changes as the flow through it changes; in the exhaust, that means less resonance and slightly more volume (compounded by partially bypassing the turbine via the wastegate; the turbine is effectively a muffler). The intake is the opposite: it gets much more resonant (and the resonances themselves shift noticeably), but far less of that energy can escape. That resonance affects the compressor flow, as can be heard in one of the videos earlier in the thread.
VTEC is a strange one. Honda engineered every single one of its cam-profile-crossover VTEC systems to produce continuous torque over that transition; i.e. the engine output is the same immediately on either side of the transition. This is only sensible. The thing is that because the torque is more or less constant over a wide range, the power delivery is linearly increasing with engine speed; that means as the rpm rises, it rises ever faster (actually, in later VTEC engines, the torque increased gradually past the transition, enhancing that peakiness). Couple that with a sudden and dramatic change in sound, and the impression is that VTEC kicked in, yo. Drive something like a DC2R at motorway speeds around the VTEC transition point (4th gear), and the continuous torque philosophy is obvious.
I tried to make a "VTEC transition sound" myself, and the exhaust sound doesn't really change that much; it's all about that intake (like in that S2000 video). Sadly, my intake modeling isn't very good, so it doesn't respond correctly; I'm not sure how it actually works, since the only thing that really changes is the "volume" (at the intake valve), but the real world effect is a substantial change in timbre. Also, GT doesn't have intake sounds.
A torque curve extracted from a dyno pull will be almost representative of steady-state, so the boost level at all rpms at full throttle can be extracted from that same run.
Turbo lag is the time it takes from throttle application for the boost to build to the steady state value for that rpm.
You reduce that by reducing the mass moment of inertia of the turbo-compressor assembly, and its friction, as well as the total volume of the turbocompressor system. Generally that means smaller turbos lag less, especially with minimal plumbing.
The boost threshold is the steady-state rpm at which the engine just begins to build boost, i.e. manifold pressure exceeds atmospheric. That is determined by the turbo-compressor spec and engine size and tuning, and is all that is available to tweak in the game.
As for sound, the 97T is the only car that seems to model turbo lag; it's not in the physics, though. That strikes me as odd. It sounds a lot like a model I made, and tested in LFS; basically the exhaust gets a bit louder and there's a lot more flow noise, fading in gradually over about half a second as the "boost" builds.
The acoustics of any ducting changes as the flow through it changes; in the exhaust, that means less resonance and slightly more volume (compounded by partially bypassing the turbine via the wastegate; the turbine is effectively a muffler). The intake is the opposite: it gets much more resonant (and the resonances themselves shift noticeably), but far less of that energy can escape. That resonance affects the compressor flow, as can be heard in one of the videos earlier in the thread.
VTEC is a strange one. Honda engineered every single one of its cam-profile-crossover VTEC systems to produce continuous torque over that transition; i.e. the engine output is the same immediately on either side of the transition. This is only sensible. The thing is that because the torque is more or less constant over a wide range, the power delivery is linearly increasing with engine speed; that means as the rpm rises, it rises ever faster (actually, in later VTEC engines, the torque increased gradually past the transition, enhancing that peakiness). Couple that with a sudden and dramatic change in sound, and the impression is that VTEC kicked in, yo. Drive something like a DC2R at motorway speeds around the VTEC transition point (4th gear), and the continuous torque philosophy is obvious.
I tried to make a "VTEC transition sound" myself, and the exhaust sound doesn't really change that much; it's all about that intake (like in that S2000 video). Sadly, my intake modeling isn't very good, so it doesn't respond correctly; I'm not sure how it actually works, since the only thing that really changes is the "volume" (at the intake valve), but the real world effect is a substantial change in timbre. Also, GT doesn't have intake sounds.
I remember the integra type-R vtec from 1999
below 4000 RPM, no power
at 6000, your body went inside the seat
at 7000, your head was pulled on the head coffin
great sensations
i don't remember the feelings of my lancia delta integrale as i only drove it one time 10 months ago
but the turbo start pushing at 2500 but above 5200-5500, not much anymore
below 4000 RPM, no power
at 6000, your body went inside the seat
at 7000, your head was pulled on the head coffin
great sensations
i don't remember the feelings of my lancia delta integrale as i only drove it one time 10 months ago
but the turbo start pushing at 2500 but above 5200-5500, not much anymore
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- Tayeedz1
@Griffith500 dropping some knowledge up in this 
I think GT would have to model a whole new engine and drivetrain system to achieve real life "Torque Physics" Along with the sound can bring this feature to light.
However, like I said before maybe it would be better to collaborate with companies that research and do this stuff for a living..... Like HKS, heck even Powerhouse Amuse.
I think GT would have to model a whole new engine and drivetrain system to achieve real life "Torque Physics" Along with the sound can bring this feature to light.
However, like I said before maybe it would be better to collaborate with companies that research and do this stuff for a living..... Like HKS, heck even Powerhouse Amuse.
- 4,329
@Griffith500 dropping some knowledge up in this
I think GT would have to model a whole new engine and drivetrain system to achieve real life "Torque Physics" Along with the sound can bring this feature to light.
However, like I said before maybe it would be better to collaborate with companies that research and do this stuff for a living..... Like HKS, heck even Powerhouse Amuse.
GT is one franchise that would benefit in MAJOR way by collaborating with turbo/supercharger manufacturers, exhaust/intake manufacturers and tire manufacturers.
PD needs a fresh approach. Their current approach worked uptil GT4. Even the most loyal fans have started to see through the cracks.
GT7 must be a whole lot more than just a current gen title or an update to GT6. It needs to venture into fresh territories and break new ground.
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The problem I foresee with working with vendors (which we must remember they are) of aftermarket performance parts is that, for my purposes, I'd be asking them sensitive questions about how their parts work, at a fundamental level.
That's industrially sensitive information, and it puts their marketing under severe scrutiny. They'd probably much rather you just faked it, but that's not good enough for me!
I'm sure you could find a no-nonsense company in any of the required fields, but whether their name and logo carries the same cachet is uncertain. Still, they got KW and Yokohama on-board. What more would it take to get Garrett (usually quite open) or, indeed, "someone" like Amuse, who always seem to know the difference between what a customer "wants" and what they actually need...
Whilst we're at it, Yamaha would be a great addition to the collaboration portfolio.
That's industrially sensitive information, and it puts their marketing under severe scrutiny. They'd probably much rather you just faked it, but that's not good enough for me!
I'm sure you could find a no-nonsense company in any of the required fields, but whether their name and logo carries the same cachet is uncertain. Still, they got KW and Yokohama on-board. What more would it take to get Garrett (usually quite open) or, indeed, "someone" like Amuse, who always seem to know the difference between what a customer "wants" and what they actually need...
Whilst we're at it, Yamaha would be a great addition to the collaboration portfolio.
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Right.
Yamaha would be a nice entity to go to as far as tire data is concerned.
For the engine-related manufacturers, they don't necessarily have to give away sensitive info. Just bonk PD on the head with a heavy rubber object, and tell em how to get the sound right!
But it doesn't end there. It's not limited to just engine and exhaust. They need to get the transmission sounds right too.
Physics: ditch the linearity and introduce more complex calculations to make on the edge driving more challenging. And I don't mean make it more nuanced to simply make it seem difficult, but challenging.. like you would IRL gracefully tame a 600+ HP beast.
I'm no expert, I know a lot of this is easier said than done.
See, I'm just not ready to give up on GT just yet, but I will if I must. Luckily I'm not on the dev team, I'm just a consumer. I get to choose.
Yamaha would be a nice entity to go to as far as tire data is concerned.
For the engine-related manufacturers, they don't necessarily have to give away sensitive info. Just bonk PD on the head with a heavy rubber object, and tell em how to get the sound right!
But it doesn't end there. It's not limited to just engine and exhaust. They need to get the transmission sounds right too.
Physics: ditch the linearity and introduce more complex calculations to make on the edge driving more challenging. And I don't mean make it more nuanced to simply make it seem difficult, but challenging.. like you would IRL gracefully tame a 600+ HP beast.
I'm no expert, I know a lot of this is easier said than done.
See, I'm just not ready to give up on GT just yet, but I will if I must. Luckily I'm not on the dev team, I'm just a consumer. I get to choose.
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- Tayeedz1
Yamaha indeed would be a great addition. Particularly for Engines and Sound. Yamaha did tune the heads for many a Toyota engine
This is actually turning out to be more complex than I thought, but hey, PD is willing to bridge the virtual divide so why not then?
I wonder if Kaz has seen this and thought "Hmmmmm"
This is actually turning out to be more complex than I thought, but hey, PD is willing to bridge the virtual divide so why not then?
I wonder if Kaz has seen this and thought "Hmmmmm"
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I hope he's rubbing his chin and hmmmming as we speak! Really want GT7 to lift itself up and resurrect the franchise.
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Super plus on the likes!
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PD already worked with Yamaha for the sound of the LFA, and if PD were working on their completely new method at that point, I could see Yamaha granting them a few patent licences whilst they were there (different departments, but eh).
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- Tayeedz1
Whaaaaaaaat, I didn't know that! Where's that piece of info from?No wonder the factory spec LFA sounds so good.
Makes me wonder why PD isn't using thwm for other cars then
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Err... I don't know where he got that from. Yamaha HAS worked with Lexus to give the LFA it's distinct exhaust notes. PD working with Yamaha? Don't know where that comes from.
@Griffith500 Could you please cite your source(s)?
Hahaha.. the way you said "whaaaat" reminds me of a scene from Borat, when he's with the driving instructor.
Yukshamaysh!!
@Griffith500 Could you please cite your source(s)?
Hahaha.. the way you said "whaaaat" reminds me of a scene from Borat, when he's with the driving instructor.
Yukshamaysh!!
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I can't seem to find an actual source. It was from before GT5 released, at least 4 years ago; somebody was talking about the LFA being in the game and they stated that they worked with Yamaha to get the engine sound right. I'm not the only one who remembers this, and it seems there's a similar "rumour" about FM4, too.
My Google-Fu is weak, though, and I'm bored now. It'd be so much easier if we could search the news on this site.
EDIT: the LFA was first spotted on the 3rd of November, so it'd be mentioned an interview after that, most likely.
My Google-Fu is weak, though, and I'm bored now. It'd be so much easier if we could search the news on this site.
EDIT: the LFA was first spotted on the 3rd of November, so it'd be mentioned an interview after that, most likely.
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I know this much for a fact: LEXUS collaborated with Yamaha to work on the exhaust notes (nothing to do with either game). Don't know about GT.
FM4 - one of the guys from the PGR dev team gave the direction to sound. Bonus: the FM4 LFA sounds eerily similar to the real thing.
As far as I know, there is no mention of Yamaha working with game devs to do justice to the in-game LFA sound. I'll Google it up though.
FM4 - one of the guys from the PGR dev team gave the direction to sound. Bonus: the FM4 LFA sounds eerily similar to the real thing.
As far as I know, there is no mention of Yamaha working with game devs to do justice to the in-game LFA sound. I'll Google it up though.
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Yamaha's involvement in Toyota's halo product goes a little bit deeper than that, as it always has done.
Nick Wiswell did not bring PGR4's legendary fidelity with him to T10, for whatever reason.
Here's a comparison video:
The biggest difference would of course be due to GT's lack of dedicated intake sound; in this case, though, there is a trace of the LFA's intake sound, but I think it's mixed in with the exhaust, so the controls don't work as they should.
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FM4 iteration of the LFA's sound is pretty faithful. S2 struggles, but doesn't quite get there.
One of the PGR4 sound guys worked with T10 on engine sounds. It's widely known.
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Okie dokie. 
I installed PGR4 yesterday, just to try to get into it again. I couldn't. The control is terrible. The engine sounds can be err... nice.. but the in between shifting sounds are not particularly pleasing; they sound the same for every car.
On the plus side though: I'm head over heels for those turbo sounds.
Tire screech sounds ain't bad either. Weather and night driving probably the best I've seen in any game (minus the PINK brake lights). The game was quite the looker back in it's day.
Wonder if these guys are planning on releasing a PGR game on current gen.
I installed PGR4 yesterday, just to try to get into it again. I couldn't. The control is terrible. The engine sounds can be err... nice.. but the in between shifting sounds are not particularly pleasing; they sound the same for every car.
On the plus side though: I'm head over heels for those turbo sounds.
Tire screech sounds ain't bad either. Weather and night driving probably the best I've seen in any game (minus the PINK brake lights). The game was quite the looker back in it's day.
Wonder if these guys are planning on releasing a PGR game on current gen.
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Not different departments. Yamaha Motor Company (a subsidiary company of the Yamaha Corporation) contribued to the development of the 1LR-GUE engine, but it was the musical instruments division of the main company that provided the audio tune for the triple exhaust of the LFA.
And yes, I'm a lot of fun at parties, why do you ask?
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- Tayeedz1
PGR4 sadly was the last PGR
Yamaha should partner for sound! Chucking that statement in the Sound thread
Now that the sound aspect of the Torque Physics has been covered, I wonder which game has actually perfected it?
I'm sure you can use some fancy Physical Science calculations in order to make some beastly algorithms to make some nice torque simulations.
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Welll, if we're going to be picky, I'd say the motor guys did the exhaust; it's a known procedure (like the Ferrari F355 and McLaren P1; different manifold types making the difference there), and it'll have been their software they used to predict and refine the result, and their experience with exhaust systems that prevailed. The three pipes are there for the same reasons, acoustically speaking, as they are on an F40 (which most likely led to the F355's sound...).Not different departments. Yamaha Motor Company (a subsidiary company of the Yamaha Corporation) contribued to the development of the 1LR-GUE engine, but it was the musical instruments division of the main company that provided the audio tune for the triple exhaust of the LFA.
And yes, I'm a lot of fun at parties, why do you ask?
They needed the instrument guys to help with the radiating surface of the intake manifold and the "sound tubes" into the cabin, and balance the overall blend of the exhaust and those other sources. It'll still have been the motor guys engineering the final result.
Anyway, as it turns out the patents I was thinking of aren't actually administered by Yamaha, but by a long-standing research partner.
I don't tend to get invited to parties.
PGR4 sadly was the last PGR
Yamaha should partner for sound! Chucking that statement in the Sound thread
Now that the sound aspect of the Torque Physics has been covered, I wonder which game has actually perfected it?
I'm sure you can use some fancy Physical Science calculations in order to make some beastly algorithms to make some nice torque simulations.
iRacing has a pretty cool drivetrain flex simulation, but the torque will still be from a look-up curve for the engine. I could see them taking that further in future. It's a bit more of a challenge if you're offering tuning, and many many more cars.
The fun thing about the way I think sound should be modeled, is that it automatically leads to a dynamic simulation of torque output. It'd be very interesting to see how expressive / stable a crude first attempt would be.
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@TayeezSA That really is too bad! The game has a lot of potential, especially if it takes a GA-like direction, and starts to offer more realistic driving.
@Griffith500 Exhaust sounds were done very nicely in PGR4.. you can really FEEL and hear them.
@Griffith500 Exhaust sounds were done very nicely in PGR4.. you can really FEEL and hear them.
