Crippling understeer in tuned MR cars

[TheROADKRAKEN]

All of my tuned up MR cars suffer horribly from understeer in low to medium speed corners. I've got an F430 and a Gallardo with over 600 hp and both of them take a LOT of effort to stay inside of corners at speed. My 1120 hp Veyron? Don't ask

I also have a 700+ hp Silverado SST which is totally useless as anything other than a drag racer.


Can somebody give advice for tuning out understeer in very high powered MR cars? And my truck?

Thanks!

More info:

Most understeer is mid to end of turn when I am trying to accelerate out.

ESPECIALLY in the Silverado, the handbrake has no effect and then suddenly snaps the car around on exit.

I can be coasting around the corner quite slowly and the steering is still crippled.

I have to almost stop and point my car through the turn in order to exit sharp curves.

Front brake bias makes the cars far too unstable under hard deceleration

Most cars, like my F430 can't have front downforce adjustment

I tried adjusting front and rear spring rates, maybe some help there?

I have an Opel Speedster with almost 250 hp that is a JOY to whip around corners, never ANY understeer so the problem might only lie with high torque cars

 

[zdawood89]

First lower the ride height.
Then try adding more front downforce and increasing front brake bias.
Add more negative camber to front tires.
Stiffen the front springs.
Lastly see if increasing toe out in the front helps.

 

[paskowitz]

Believe it or not sometime giving the throttle a mid corner jab can send some weight off the front tires. Obviously this will cause rear tire grip loss and possibly oversteer, but sometimes when you are understeering badly this will get your out of it.

 

[TheROADKRAKEN]

Believe it or not sometime giving the throttle a mid corner jab can send some weight off the front tires. Obviously this will cause rear tire grip loss and possibly oversteer, but sometimes when you are understeering badly this will get your out of it.

updated OP.

NOW WAY will this work. Every time I hit the gas mid-turn it almost steers me in the opposite direction! Like it's being pushed out of the turn by the rear wheels

 

[GTRedline]

Toe in up front will increase your turn in, but weight transfer plays a big part. All the weight is in the rear, after you intial braking there's nothing keeping the front wheels planted. Try stiffer spring out back, or a little higher ride height in the back.

 

[TheROADKRAKEN]

First lower the ride height.
Then try adding more front downforce and increasing front brake bias.
Add more negative camber to front tires.
Stiffen the front springs.
Lastly see if increasing toe out in the front helps.

updated OP

All of these cars are lowered -10

I will try camber and toe.

Spring rate not helping

 

[zdawood89]

Ok after reading that it under-steers heavy exiting a corner, its definitely a front downforce problem. The front of the car is not getting enough grip and it is forced to cripple its way out the turn until the chassis is straightened up with the track.

In this case you want to induce the car to over-steer entering the turn.
Really increase the front brake bias.
-3 degrees of front camber and -2 degrees rear (benchmark, you can fine tune it as you feel it out)
Stiffen the rear suspension to prevent the car from lurching backward as you accelerate out of the turn.

 

[zdawood89]

When tuning keep in mind...

Springs = Higher value is softer
Dampers = Higher valus is harder
Roll bars = Higher value is stiffer

(See this thread: https://www.gtplanet.net/forum/showthread.php?t=134850&highlight=spring+rate)

 

[TheROADKRAKEN]

Ok after reading that it under-steers heavy exiting a corner, its definitely a front downforce problem. The front of the car is not getting enough grip and it is forced to cripple its way out the turn until the chassis is straightened up with the track.

In this case you want to induce the car to over-steer entering the turn.
Really increase the front brake bias.
-3 degrees of front camber and -2 degrees rear (benchmark, you can fine tune it as you feel it out)
Stiffen the rear suspension to prevent the car from lurching backward as you accelerate out of the turn.

I will definitely try the camber/toe solution.

I have the brakes about 8/7 or 8/6 on these cars and I can barely cope with the instability under hard braking. Even if I brake in a totally straight line, any bumps of inconsistencies in the road surface make the car swerve or worse. If I have to steer around cars, it's a sure bet the car will end up in the barrier or dirt on the outside.

When tuning keep in mind...

Springs = Higher value is softer

...you just blew my mind o_0

OK, THIS MIGHT BE THE PROBLEM

*face/palm*

 

[NLxAROSA]

When tuning keep in mind...

Springs = Higher value is softer

(See this thread: https://www.gtplanet.net/forum/showthread.php?t=134850&highlight=spring+rate)

Read the responses in the thread too, you're wrong. Higher value=stiffer, but engine flaw makes this work the other way around on certain cars (mostly FWD and AWD).

 

[Rotary Junkie]

Mild front toe-in and rear toe-out will help the vehicle rotate, however, certain cars are simply NEVER going to get around low-speed corners well due to being very long and having a narrow track width for their length.

As I mentioned in the other thread, the spring rates ARE the right way round but when you go too extreme you either get crippling understeer or laughable amounts of uncontrolled oversteer. The car dictates what is "too extreme", however... So that Silverado will probably like very stiff front springs/stabilizers and soft rear.

 

[Brokenparts]

try lowering your bump stiffness and sway bars in the front. when you turn the weight transferes to the outside tires and if the front end is softer, it will dive and bite the track. you could also stiffen up the rear bump stiffness or try adding some negative toe in the rear of the car to help it rotate.... some people dont like it, I do 👍

 

[zdawood89]

Read the responses in the thread too, you're wrong. Higher value=stiffer, but engine flaw makes this work the other way around on certain cars (mostly FWD and AWD).

Thanks for pointing that out, I will have to play with it how that one later post in the thread did with the Ferrari California.

In short, it just means you need to try different setups, see which is fastest.

 

[SleazyBig slim]

All of my tuned up MR cars suffer horribly from understeer in low to medium speed corners. I've got an F430 and a Gallardo with over 600 hp and both of them take a LOT of effort to stay inside of corners at speed. My 1120 hp Veyron? Don't ask

I also have a 700+ hp Silverado SST which is totally useless as anything other than a drag racer.


Can somebody give advice for tuning out understeer in very high powered MR cars? And my truck?

Thanks!

More info:

Most understeer is mid to end of turn when I am trying to accelerate out.

ESPECIALLY in the Silverado, the handbrake has no effect and then suddenly snaps the car around on exit.

I can be coasting around the corner quite slowly and the steering is still crippled.

I have to almost stop and point my car through the turn in order to exit sharp curves.

Front brake bias makes the cars far too unstable under hard deceleration

Most cars, like my F430 can't have front downforce adjustment

I tried adjusting front and rear spring rates, maybe some help there?

I have an Opel Speedster with almost 250 hp that is a JOY to whip around corners, never ANY understeer so the problem might only lie with high torque cars

Sorry buddy but those cars you mentioned all understeer by nature. You can tune the hell out of the suspension to take away some understeer but you will never rid of it completely in those cars. I suggest the Suceda? 430. It handle much better then the regular 430 and only has slight understeer, great car, I hate the origional 430. I have a V10 Audi R8, its mid engined though its also 4wd, and its a beast, great handling car, I wasn't able to enter the MR race with it though because of its 4wd. I would suggest the Ford GT, cheap for a mr super car at only 150k and no understeer.

 

[TheROADKRAKEN]

Sorry buddy but those cars you mentioned all understeer by nature. You can tune the hell out of the suspension to take away some understeer but you will never rid of it completely in those cars. I suggest the Suceda? 430. It handle much better then the regular 430 and only has slight understeer, great car, I hate the origional 430. I have a V10 Audi R8, its mid engined though its also 4wd, and its a beast, great handling car, I wasn't able to enter the MR race with it though because of its 4wd. I would suggest the Ford GT, cheap for a mr super car at only 150k and no understeer.

Believe it or not, this was the most helpful post

I love my Ford GT!!!

 

[leoyblam]

I guess need to check from the basic theory. I'm not sure coz haven't bought any MR car yet in this game.

Developed already in GT4, I realize that MR is theoretically cool but not really the case in real life. Like what you have experienced, the understeering.

Think about the car physics. If you are accelerating, the weight would move to the rear side. That means the front wheels would have less traction. That's the point. Less traction so not enough force to help you turning. Also you may need to set your camber angle fitting your style of driving.

I would suggest you to tune your suspension all the way stiffer, see if it helps?

 

[VTiRoj]

All of my tuned up MR cars suffer horribly from understeer in low to medium speed corners. I've got an F430 and a Gallardo with over 600 hp and both of them take a LOT of effort to stay inside of corners at speed. My 1120 hp Veyron? Don't ask

I have an Opel Speedster with almost 250 hp that is a JOY to whip around corners, never ANY understeer so the problem might only lie with high torque cars

What tyres are you using? If it's sports tyres, you're overpowering them with that much power. Hence why the Speedster handles so well compared to the F430 and Gallardo. Lowering the power to a more reasonable level would put less strain on the tyres and give you better handling. If you're using racing tyres, then you should adjust your setup like Rotary Junkie mentioned and your cars should handle fine.

 

[aikitim]

ill post the setup ive got on my 430 scuderia tomorrow - it fixed the same problem...

 

[Heuer21]

I think you need to re-learn how to drive lines through corners... I also have F430 loaded, ZR-1 RM, Saleen S7...
None of them understeer unless you take a corner wrong. When you get high horsepower cars handling decreases because you are heavier and going much faster into turns.

Also, turn your driving aids off. The driving aids help keep the car controllable.... AKA Understeer...just like real cars.

 

[probull3t]

I'm kinda puzzled as to why you're saying a tuned Gallardo would have massive understeer. I maxed mine out with everything and it is insanely fast through the corners.

 

[daveyules]

I noticed that if you set up your suspension too stiff it can cause serious understeer. try softening up the suspension to allow the car's weight to help rotate it.

otherwise though I just tuned up my murcielago SV and it is truly an incredible car. never thought I'd say that.