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Jezza819
28-10-2017, 20:03
I'm talking about cars when you hit the brakes it feels like one side grabs and pitches the car in that direction. The worst one I've got is the Ginetta GT4, go hit the brakes, the car dives to the right. I can't drive it. Oddly enough I had the same problem with the V8 Supercar at Bathurst. Going down into The Dipper and then into the Elbow it wanted to pitch sideways into the wall when going over the bumps when braking. But it hasn't done that at other bumpy tracks I've driven the car at.

Is it a brake pressure adjustment issue? Somewhere else in the setup that needs to be adjusted?

blinkngone
28-10-2017, 22:45
Hi Jezza, sorry you don't have a lot off responses yet. Are you using default set ups and which track, so I could try an replicate the problem. The only time I have a problem with the car pulling it has been when I had the springs messed up, too soft and a little too much weight transfer going into a corner and I am not able to hold a line. I suppose there are other reasons as well. I suppose if the dampers are way off you could have the problem but unless you have adjusted these yourself I don't know. If you don't have the brake bias and pressure correct you are going to lose steering control with the front brakes locked/nearly locked. I've done this myself at Maggots/Aintree on Silverstone National. Trying to brake and steer right and instead go left off track.

hkraft300
28-10-2017, 22:54
.

Is it a brake pressure adjustment issue? Somewhere else in the setup that needs to be adjusted?

Reduce brake pressure and go easy to avoid lock up.
A bit less coast ramp angle on the diff may help.

blinkngone
29-10-2017, 00:10
Hi Jeeza, me in my Ginetta GT4 at Silverstone National.
Normal brake setup.
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Exaggerated bias and balance.
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There I go left off track while trying to turn right.

peterCars
29-10-2017, 03:09
not a helpful comment, but the commentators in F1 qualifying last week , commenting on Hamilton's superb performance, mentioned that he uses the brakes too to steer the car. maybe has a secret lever in there or something.

hkraft300
29-10-2017, 05:16
...commenting on Hamilton's superb performance, mentioned that he uses the brakes too to steer the car..

It is the ancient and secret art of trail braking.
Only the bravest, hardest of men are invited to the lost racetrack on a moonlit night, once a generation. The art is passed down from master to disciple. Guarded, hidden amongst mortals.

Blaine Jr
30-10-2017, 07:03
Almost always when a car pulls hard to one side under braking you are locking the rears. Sometimes it's the differential settings but 9 times out of 10 your locking the rear up. To alleviate this you have a few options;


Be more gentle on the brakes and delay your downshifts.
Adjust the brake bias a couple of clicks to the front.
Reduce overall brake pressure.



I almost never suggest reducing overall brake pressure by more than a few percent, as then it's harder to maximize the braking potential of the car. I suggest you start by moving the bias 3-4 clicks to the front and then work on your footwork. As you get better and better at braking start moving the bias further to the rear to maximize braking potential and reduce braking distance.

blinkngone
30-10-2017, 09:48
Almost always when a car pulls hard to one side under braking you are locking the rears. Sometimes it's the differential settings but 9 times out of 10 your locking the rear up. To alleviate this you have a few options;


Be more gentle on the brakes and delay your downshifts.
Adjust the brake bias a couple of clicks to the front.
Reduce overall brake pressure.





I almost never suggest reducing overall brake pressure by more than a few percent, as then it's harder to maximize the braking potential of the car. I suggest you start by moving the bias 3-4 clicks to the front and then work on your footwork. As you get better and better at braking start moving the bias further to the rear to maximize braking potential and reduce braking distance.

It kind of depends on the cars and where you have your brake sensitivity(mine is at 59) as well. 61/39 is my bias for the GT4, others may differ.

Jezza819
30-10-2017, 14:06
Almost always when a car pulls hard to one side under braking you are locking the rears. Sometimes it's the differential settings but 9 times out of 10 your locking the rear up. To alleviate this you have a few options;


Be more gentle on the brakes and delay your downshifts.
Adjust the brake bias a couple of clicks to the front.
Reduce overall brake pressure.



I almost never suggest reducing overall brake pressure by more than a few percent, as then it's harder to maximize the braking potential of the car. I suggest you start by moving the bias 3-4 clicks to the front and then work on your footwork. As you get better and better at braking start moving the bias further to the rear to maximize braking potential and reduce braking distance.

I usually take a car down to 85% as a basis to work from which is where I had the Ginetta GT4 and it was still binding. I moved it down to 80% and it seems to have fixed it. The V8 Supercar on the other hand seems to be another story. I think it was at 90% to begin with and I didn't really have any issues with it even at Long Beach with all of it's bumps. But at Bathurst it just won't handle all of those dips and bumps without jerking into the wall or off track. It's down to 75% now and it's still doing it. Oddly enough it did it at Nurburgring GP also. I might try the bias thing next before giving up on it.

Fight-Test
31-10-2017, 16:57
I usually take a car down to 85% as a basis to work from which is where I had the Ginetta GT4 and it was still binding. I moved it down to 80% and it seems to have fixed it. The V8 Supercar on the other hand seems to be another story. I think it was at 90% to begin with and I didn't really have any issues with it even at Long Beach with all of it's bumps. But at Bathurst it just won't handle all of those dips and bumps without jerking into the wall or off track. It's down to 75% now and it's still doing it. Oddly enough it did it at Nurburgring GP also. I might try the bias thing next before giving up on it.

85% is my starting point for all cars also. Its a good base number to use.

morpwr
01-11-2017, 10:43
I usually take a car down to 85% as a basis to work from which is where I had the Ginetta GT4 and it was still binding. I moved it down to 80% and it seems to have fixed it. The V8 Supercar on the other hand seems to be another story. I think it was at 90% to begin with and I didn't really have any issues with it even at Long Beach with all of it's bumps. But at Bathurst it just won't handle all of those dips and bumps without jerking into the wall or off track. It's down to 75% now and it's still doing it. Oddly enough it did it at Nurburgring GP also. I might try the bias thing next before giving up on it.

I could be mistaken but doesn't the v8 supercar have a locked diff? If so you pretty much can only brake in a straight line or be extremely careful about trying to brake while turning especially with all the off camber turns on hills at Bathurst.

Jezza819
01-11-2017, 12:42
I could be mistaken but doesn't the v8 supercar have a locked diff? If so you pretty much can only brake in a straight line or be extremely careful about trying to brake while turning especially with all the off camber turns on hills at Bathurst.

I'm not sure. I don't really understand the differential stuff. However I did look at that in the tuning menu and it said "Spool on" whatever that means and yes I have looked at the differential tutorial in this forum and I still don't understand it.

Bealdor
01-11-2017, 12:58
I'm not sure. I don't really understand the differential stuff. However I did look at that in the tuning menu and it said "Spool on" whatever that means and yes I have looked at the differential tutorial in this forum and I still don't understand it.

Spool means the diff is completely locked.

blinkngone
01-11-2017, 13:27
Yeah it's just one of the odd things in the game, you can choose a spool LSD for an FA car(I don't know if any F1 teams are using this, maybe at Monaco where it would really help with the tight turns) but some cars(Falcon) are locked with a spool and you have no choice. If you check out some Nascar websites they use a locked(spool) differential for ovals like Daytona and Texas in the game but claim they don't use it on road courses, wonder why(even the Fusion Stockcar gives you an option), yet the Falcon is locked to spool on road courses...

hkraft300
01-11-2017, 15:20
...yet the Falcon is locked to spool on road courses...

It's a regulation thing. V8SC are mandated spool diffs.
Take it off it'll become an overweight GT essentially.
Also makes the V8SC difficult to manage and unique by design.

morpwr
01-11-2017, 15:45
I'm not sure. I don't really understand the differential stuff. However I did look at that in the tuning menu and it said "Spool on" whatever that means and yes I have looked at the differential tutorial in this forum and I still don't understand it.

Basically a spool makes the car not want to rotate. The minute you get on the gas it will want to go straight in the direction the rear wheels are pointed. Same goes for braking you want to get as much done as possible while the car is straight. With a spool the inside and outside tires are locked together and being the radius of a turn is different on both wheels the inside tire normally skips. In a real car you can actually hear it squeal even at slow speeds and aren't a lot of fun to drive on the street.lol

morpwr
01-11-2017, 15:52
Yeah it's just one of the odd things in the game, you can choose a spool LSD for an FA car(I don't know if any F1 teams are using this, maybe at Monaco where it would really help with the tight turns) but some cars(Falcon) are locked with a spool and you have no choice. If you check out some Nascar websites they use a locked(spool) differential for ovals like Daytona and Texas in the game but claim they don't use it on road courses, wonder why(even the Fusion Stockcar gives you an option), yet the Falcon is locked to spool on road courses...

You wouldn't want to run a spool with tight turns unless rules forced you too. It wouldn't help at all with tight turns. The lsd would allow the car to rotate in the corners much better.

bradleyland
01-11-2017, 16:12
Almost always when a car pulls hard to one side under braking you are locking the rears. Sometimes it's the differential settings but 9 times out of 10 your locking the rear up. To alleviate this you have a few options;


Be more gentle on the brakes and delay your downshifts.
Adjust the brake bias a couple of clicks to the front.
Reduce overall brake pressure.



I almost never suggest reducing overall brake pressure by more than a few percent, as then it's harder to maximize the braking potential of the car. I suggest you start by moving the bias 3-4 clicks to the front and then work on your footwork. As you get better and better at braking start moving the bias further to the rear to maximize braking potential and reduce braking distance.

Lots of folks overlook this one. Aggressive downshifting only applies braking force to the driven wheels. So aggressively downshifting a rear-drive car is going to shift your braking effort toward the rear. You can dial in 75/25 (front/rear) brake bias, but it won't matter if you're slamming through downshifts at maximum RPM.

I've also noticed that engine braking seems to be far more destabilizing in pCARS 2 than it was in pCARS 1. In pCARS 1, you could slam down through the gears with reckless abandon. Try the same thing in pCARS 2 and you'll end up swapping ends pretty quickly. Go drive the Ferrari GTB4 with the stable setup around Algarve. If you downshift aggressively, you can slide the car around as if you were using the handbrake.

I recommend taking a page from actual race car drivers. If you listen carefully, you can hear that most drivers do their braking with the car's brakes, and fire off a rapid series of downshifts at the very last moment, just before turn-in. They do this because:


Braking systems on modern race cars are more than capable of braking at the limit of the tyres. Thus, engine braking only serves to disrupt brake balance adjustment and destabilize the car.
It saves the gearbox.

We don't have to worry about the latter, but the former is very important to maintain maximum stability (and thus grip).

Jezza819
01-11-2017, 20:08
It's a regulation thing. V8SC are mandated spool diffs.
Take it off it'll become an overweight GT essentially.
Also makes the V8SC difficult to manage and unique by design.

When I saw that I thought I had better leave that alone as it might be something to do with a requirement for that car. Turns out that was correct.

Ball325
01-11-2017, 21:24
are you running ABS? the ABS in this game can cause a car to wander a bit under braking as individual wheels lock up and the ABS system modulates the pressure.

morpwr
01-11-2017, 22:34
When I saw that I thought I had better leave that alone as it might be something to do with a requirement for that car. Turns out that was correct.

Think of cars with spools as more point and shoot from corner to corner on a road track . Irl guys cheat around the spool by using different diameter tires in oval racing. We used to over inflate the outside tires and stick them in the sun so they would grow and stay bigger. Then just inflate the insides to the pressure we ran so they didn't grow any bigger.

blinkngone
01-11-2017, 22:59
Only one person in this group likes the car(not me). It's fast but I have problems with the brakes, I always have these so not specific to this car. Can't brake the left very well in sector 2 and the first left of sector 3 leading uphill to the esses is worse.
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blinkngone
02-11-2017, 00:13
The spool works at the Speedway, Falcon easily is fine here. The Ferraris aren't using the spool for some reason even though under the regulations they are allowed to. I made 1 run with a spool in the Ferrari.
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blinkngone
02-11-2017, 00:27
NSX with spool blows off even the Falcon.
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blinkngone
02-11-2017, 00:56
Huracan with spool needs work, probably bad aero for Speedway.
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morpwr
02-11-2017, 11:51
If I'm not mistaken the only reason a spool is mandated in some classes started years ago to keep cost down. Guys with money are going to get an advantage buying a diff some cant afford. So you really would never want to run one unless forced to if you have to turn. On speedways its not as much of a problem because the turns are big sweeping ones and irl youd play with tire diameter to help the issues the spool causes.

blinkngone
02-11-2017, 12:38
If I'm not mistaken the only reason a spool is mandated in some classes started years ago to keep cost down. Guys with money are going to get an advantage buying a diff some cant afford. So you really would never want to run one unless forced to if you have to turn. On speedways its not as much of a problem because the turns are big sweeping ones and irl youd play with tire diameter to help the issues the spool causes.
Yeah, that's pretty much what I read about the Falcon, a cost saving measure for the series. I think the reason it's not really a great speedway car for me is I can't get the rear wing out of the airflow(running 0 downforce) so it slows me down compared to the NSX, the horsepower advantage is negated. Another thing I noticed about the Falcon is if you move up the track it slows dramatically so the only option is the very inside groove. I'm 0.220 out of 1st but I can't see working on it when I am already over 2 tenths quicker with the NSX than the WR Falcon with little work. Both cars could be improved but I think the outcome might remain the same. I can't change tire diameter so I over pressure the right sides which I can get away with in TT. I have major braking issues with the GT3's at some tracks, and the Falcon as well, but for some reason I brake the GTE's better.

morpwr
02-11-2017, 13:06
Yeah, that's pretty much what I read about the Falcon, a cost saving measure for the series. I think the reason it's not really a great speedway car for me is I can't get the rear wing out of the airflow(running 0 downforce) so it slows me down compared to the NSX, the horsepower advantage is negated. Another thing I noticed about the Falcon is if you move up the track it slows dramatically so the only option is the very inside groove. I'm 0.220 out of 1st but I can't see working on it when I am already over 2 tenths quicker with the NSX than the WR Falcon with little work. Both cars could be improved but I think the outcome might remain the same. I can't change tire diameter so I over pressure the right sides which I can get away with in TT. I have major braking issues with the GT3's at some tracks, and the Falcon as well, but for some reason I brake the GTE's better.

Did you try dropping the rear of the car some or possibly soften the rear springs to push it down with the downforce at speed? Moving up the track will only work if you can carry all the speed through the corner the inside line is always shorter distance.

blinkngone
02-11-2017, 13:15
Did you try dropping the rear of the car some or possibly soften the rear springs to push it down with the downforce at speed? Moving up the track will only work if you can carry all the speed through the corner the inside line is always shorter distance.
Hi, no I assume the HBR guys(1 and #2) did a good job with their Falcon setups. I tweaked the NSX so they have a target to shoot for.
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blinkngone
02-11-2017, 13:50
With the GTE's you can change the final drive, without this it is slower than a GT3 and the Falcon.
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I copied this from the IMSA rules so the locked Gear Sets for GT3 in game must be for some other European GT3 requirement. IMSA site says it complies with FIA so don't know what that means. Blancplain?

b. Manufacturers may declare three (3) gear sets via the Technical Eligibility Form:
i. Daytona Gear Set
ii. Intermediate Gear Set (must be as defined in the Homologation Form for the Car Model)
iii. Short/Street Circuit Gear Set

For some reason at Daytona the Ford GT gets the highest gear so of course it is fastest, don't know why it gets this advantage. The Ferrari is a dog, needs to go to a no kill shelter.

Nyreen
03-11-2017, 13:32
I recommend taking a page from actual race car drivers. If you listen carefully, you can hear that most drivers do their braking with the car's brakes, and fire off a rapid series of downshifts at the very last moment, just before turn-in. They do this because:


Braking systems on modern race cars are more than capable of braking at the limit of the tyres. Thus, engine braking only serves to disrupt brake balance adjustment and destabilize the car.
It saves the gearbox.

We don't have to worry about the latter, but the former is very important to maintain maximum stability (and thus grip).

I was very interested by what you said, but when I've tried to actually delay my downshifts and quickly 5 to 1, the rear just spun out. So I actually checked if this was true.

https://www.youtube.com/watch?v=pxOl0b8K6FY

https://www.youtube.com/watch?v=4GBXjPKmoVM

Seems they are just downshift normally to me. They make sure to shift at the same RPM to keep the tires gripping, totally conventional.