Rev-matched upshifts

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I posted this in the GT4:P forum also, but not everyone goes in there. Although I am basing this on my experiences in that version of the GT series, I think all versions of GT have this problem to address, and therefore everyone can identify.

so...

Am I the only one who is annoyed by the rev-matched upshifts?

Take an S2000 for example. You launch the car from the starting line, rip through first gear, shift at redline, and.... nothing. You coast for a good 2 1/2 seconds while the RPM's drop down to match the next gear, and then it resumes acceleration, albeit without the tiniest upset in the drivetrain. The only way you will spin in 2nd gear is if you have enough power to then overcome the traction you have in 2nd gear.

In real life, you run up through 1st gear, stab the clutch, row the shifter into second gear, and stab the gas again as you release the clutch. This quick mechanical change into the next gear only allows the RPM's to drop about 750 RPM or so, because you do it quickly. So in this case, you release the clutch with the RPM's at, say, 8,250 RPM, when infact in 2nd gear at that speed you should be at 6,000 RPM. This results in a solid chirp of the tires, a kick in the butt, and two small patches of rubber being laid down as you continue your sprint up through the gears. In real life, just about any manual transmission car with a healthy clutch can get a tiny bit of wheel spin in 2nd gear, or even 3rd gear, because of speed of the flywheel spinning giving the drivetrain a kick.

The upside of this real-life scenario over the GT4 style shift is that you can get into the next gear and resume accelerating sooner, and also, the inertia of the flywheel spinning at 8,000 RPM translates into a kick of energy sent to the back wheels upon completion of the shift. The downside to this is that you upset the drivetrain, and if you were to upshift in a corner while accelerating, you could easily enduce oversteer when the rear tires broke free. In real life, this is a big issue to deal with.

These events change when you decide to replace the flywheel (less mass = less inertia to break the tires free on a non-rev-matched shift), and when you change the clutch (the clutch grabs firmly, and instead of the revs sliding down to match the drivetrain speed, they snap down, more directly).

How to simulate this though? How do you allow the driver to shift for both maximum smoothness, or maximum acceleration?

Could you make the shift button act as the clutch also? Press in the button, hold it, and then release it to pop the clutch in the next gear? So you run up from 1st to 2nd gear, hit the button as fast as possible for quick shift, and a loud bark from the tires. Hit the first corner, upshift from 2nd to 3rd as you pass the apex, and this time hold the button for a second or two to let the revs drop and match, to prevent a jolt to the rear wheels? If you do this, do you make the 'shift' button automatically disable the throttle, or does the throttle button remain active so that you have to 'lift' in order to shift? You could use the analog feature of the button to detirmine how fast the clutch is released. should both be available, and the method changes when the car is equipped with a sequential gear box vs. a conventional gated tranny?

any others feel this way?
 
well, all I can tell you is that GT4 will be much more realistic then GT3, I'm not too sure how they did that but they did.

Honestly I don't think you'll be able to have so much control over the shifting..Maybe GT5..2007...
 
Actually i think a suitable shifting simulation without complicating things would be this;

In order to upshift, the game will not read a shift if the acceleration button is depressed. so for a proper shift, you must release the X button, then shift, then resume acceleration. A quicker, "snappier" shift will be judged by how quick your fingers can move, and a smooth shift can be done by using the pressure sensitive feature to smooth out the operation.
 
However, that's not the way race cars work. Sequential transmissions have a sensor that detects movement of the shift lever or paddle, and cuts fuel flow to the engine automatically (and momentarily) during the shift. The driver's throttle foot stays down the whole time.

That would work for street cars, though.
 
I don't care about simulating the lift between shifts, as much as I do the time it takes to complete a shift, and the need to let the revs free-spin down to just the right spot before the computer decides that you are allowed to resume accelerating.
 
The start is all important, and we just don't have the clutch control we should have. The only real solution is for the DF3 to have a h-shifter and clutch pedal.

Maybe... someday.
 
Using the recently discovered gear change 'bug', I will test this again tonight. Actually I already tested, but didn't measure the time exactly. You see what's been bothering me about this, is that I thought Kazunori actually has an S2000. So you'd expect the speed for it to be correct.
 
Arwin
Using the recently discovered gear change 'bug', I will test this again tonight. Actually I already tested, but didn't measure the time exactly. You see what's been bothering me about this, is that I thought Kazunori actually has an S2000. So you'd expect the speed for it to be correct.
Click to expand...
He doesn't own an S2000 to my knowledge, but you probably know more than me ;)

This "gear shift bug", does it work with Prologue? If it does, I will try to look into it aswell if I have some free time. Anyways, thank you for testing this for us.
It is a good topic of discussion.
 
so from what I understand from that thread, if you tap reverse when you are at/in redline, it will resume acceleration in the next gear?
 
Ok, I got a time of about 6.5 seconds using my new understanding of the way the clutch works in GT. Here's what I do.

I wait until the lap counter starts. I now press the brake pedal and rev the car all the way up. Notice that keeping the brake on prevents the car from releasing the clutch. The gearlight stays dim no matter how much revs you make.

At the moment the counter says 3 seconds have passed, I release the brake and the car shoots away. You will see the clutch light come on quickly. At about 65km/h I tap the reverse button for a super fast shift. The clutch comes off and on really quickly, but because I keep accellerating the car two things happen: 1. the clutch slips as it struggles to reengage. 2: while slipping however it already continues to accellerates the car.

Notice that if you let go of the gas when tapping the reverse button (which we understand to mean pressing the clutch pedal), the moment you press the gas again the clutch will be reapplied.

I'm not sure how you can lose only 750rpm though as the difference between engine/clutch and flywheel rpms after the gearchange are what decides the required rpm drop, or? So in this car you would always lose about 2000rpm, slightly less for the higher gears? Or did I misunderstand something? (i've been reading up on gears and clutches the last few days)
 
Amazing tests there Arwin. I have played with the reverse and notice some of this behavior, but now I will have to give it more attention after reading your review of the "clutch" button. Thanks.
 
maybe most dont know this...but in real life, the fastest way to shift a car is not to pop the clutch above the next gears rpm, but to be below that rpm and accelerating the motor towards that rpm at the instant u shift. this way, minimal momentum is lost. popping the clutch above the next gear rpm will slow ur motor down if u have enough traction to not spin (and spinning isnt productive anyway) and u then lost all the momentum that ur motor had as it was accelerating and now it must just use straight hp to accelerate the car instead of being assisted by the inertia of an accelerating flywheel and all reciprocating mass thats powering it. just thought i'd let u guys know.
 

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