FITT Race Car Tuner Challenge

[XDesperado67]

So working on a BMW for the 625PP class. Nice car pretty good drive, but I'm having some nasty weight transfer problems. Not sure what to do about them and how much of it is my poor driving at that high a level. If the rear starts to break free while cornering easing off the throttle results in the front end snaping violently in the opposite direction. Any reccommendations on how to correct this? Or is it a simple case of my lack of driving skills?

 

[Ridox2JZGTE]

So working on a BMW for the 625PP class. Nice car pretty good drive, but I'm having some nasty weight transfer problems. Not sure what to do about them and how much of it is my poor driving at that high a level. If the rear starts to break free while cornering easing off the throttle results in the front end snaping violently in the opposite direction. Any reccommendations on how to correct this? Or is it a simple case of my lack of driving skills?

I would love to give the car a try if you don't mind, is it okay if send you FR ? This is the M3 GTR right ?

 

[tronrider345]

On the M3 GTR, use ballast until you can achieve a 49-51 or 48-52 weight distribution.

 

[XDesperado67]

@RIdox Yes it is the M3 GTR wasn't really ready to place on share quite yet as it's more of a quick rough tune so far, but I can share it tomorrow and send FRs then.

@Tronrider I'd considered trying some ballast to move it from a 50/50 weight distribution but was hoping to save that as a last resort. The car when maxed out only makes around 640PP with full aero so there isn't a lot of room to play with variables like extra weight without it having potential detrimental effects on the performance.

 

[ugabugaz]

Hmm, Interesting problem you have there XD. Since I don't know what the setup looks like, I can't really help out. Perhaps try stabilizing the rear a bit (+rear toe or more rear camber)? Or try stiffer springs maybe? Dunno really...

 

[Ridox2JZGTE]

@RIdox Yes it is the M3 GTR wasn't really ready to place on share quite yet as it's more of a quick rough tune so far, but I can share it tomorrow and send FRs then.

Don't worry if it's not ready to share yet, in the mean time you can try my cars, the Civic is real fun car and the ISF have a decent tune already, you can try the toe and camber settings from the car and use it on the M3 GTR, see if it helps. The ISF RM is tuned for better turn in on chicanes, stability under brakes and nice corner exits, just like the Civic , I'll send you FR in a bit, so you can access my cars.

 

[XDesperado67]

Hmm, Interesting problem you have there XD. Since I don't know what the setup looks like, I can't really help out. Perhaps try stabilizing the rear a bit (+rear toe or more rear camber)? Or try stiffer springs maybe? Dunno really...

Started with very firm springs, positive rear toe and pretty good camber. Actually been reducing the spring rates and it's been helping some. Problem only becomes apparent in high speed cornering like the S-curve through the sand on the back side and the final turn leading to the front straight. When you let off the throttle instead of it just bringing the rear back in line and/or inducing mild understeer, instead the front tends to snap violently out towards whichever side the rear was sliding towards. It's like the rear suddenly has massive grip and just flings the front in the other direction.

I've dealt with cars that understeer and cars that oversteer in the past but this is a relatively new issue for me...can't recall having another car react quite like this...

 

[CyKosis1973]

Sounds like the rear is loosing grip and then getting it all back the second you lift off. Have you tried adjusting the front suspension?? Contrary to what others have found, I tend to use positive toe at the front now, for anything other than FWD.

Otherwise, stiffen up your diff then Sir, specifcally INT and BRAKE. If you've tried various rear spring rates, toe and camber, then I'm not sure what else to suggests, without driving the beast. Sometimes I have to lap and lap and lap until I realise what the problem is.

With my 500PP Pocket Monster, I've had to use stiffer diff settings than I have before...

{Cy}

 

[krenkme]

I just drove your 625PP entry and it's not bad. You might be able to find a bit of a lap time gain if you actually used the approved tires for the 625PP class - Racing Mediums.

I will send you a PM with a few other things to try. Your tune (with race mediums) is in the ballpark with my Corvette tune. A few tweaks and it may be there.

Racing Mediums you say?... that just might be crazy enough to work

Thanks for the help. I hope I get a chance to try it out and improve it before the deadline

So working on a BMW for the 625PP class. Nice car pretty good drive, but I'm having some nasty weight transfer problems. Not sure what to do about them and how much of it is my poor driving at that high a level. If the rear starts to break free while cornering easing off the throttle results in the front end snaping violently in the opposite direction. Any reccommendations on how to correct this? Or is it a simple case of my lack of driving skills?

What are your damper settings might I ask?

 

[tronrider345]

Any one already worked on the 500pp at SPA?

I can't use this account for SPA , I bough the family pack and unfortunally it wasn't there to download.

 

[Ridox2JZGTE]

@ TronRider345 : I already have my Civic on share - the one for Spa, it ran 2:35 low, will be seeing 2:34 soon You can try it if you want. Still not finished yet, I have someone test driving it now at Spa, I hope the Stig could handle the little monster with big turbo

Actually I just did 2:34 earlier, and my test driver "teh stig" just reported to me 2:32.xxx

OMG, "teh stig" just said he got down to 2:30.xxx and seeing 2:29 is within reach

 

[tronrider345]

Can you or anyone help me , honestly I know how to tune , but I never understood how the hell is toe suppoused to do and how do I set it ?

 

[Ridox2JZGTE]

Can you or anyone help me , honestly I know how to tune , but I never understood how the hell is toe suppoused to do and how do I set it ?

Is it an FF ? with FF I usually have front positive toe for better turn in and more grip when cornering, rear would be negative to help the rear rotate when entering a corner under heavy braking, of course trail braking would immensely help too. Or you can have both negative for more stability, having positive front on FF and negative rear will make the car wander on high speed straight beware.

 

[tronrider345]

FR , Lexus IS200.

I can set it to share ?

 

[Ridox2JZGTE]

FR , Lexus IS200.

I can set it to share ?

You can if you want to, like I do. I don't mind if others driving them before the deadline, sometimes a feedback can also be worthwhile For FR, I would suggest to try my ISF RM for 625PP, it can be used on other tracks, maybe you can see some of my settings and maybe they will benefit you

 

[tronrider345]

You can if you want to, like I do. I don't mind if others driving them before the deadline, sometimes a feedback can also be worthwhile For FR, I would suggest to try my ISF RM for 625PP, it can be used on other tracks, maybe you can see some of my settings and maybe they will benefit you

I have the Lexus IS200 Race Car for 500pp not the ISF.

And okey thanks for the help!

 

[Adrenaline]

Can you or anyone help me , honestly I know how to tune , but I never understood how the hell is toe suppoused to do and how do I set it ?

Rear toe:
Positive: Stability, tendency to understeer
Negative: Agility, tendency to oversteer

Front Toe:
Positive: Better corner exit
Negative: Better corner entry

Find the balance that best suits the tune you have.

 

[Motor City Hami]

Rear toe:
Positive: Stability, tendency to understeer
Negative: Agility, tendency to oversteer

Front Toe:
Positive: Better corner exit
Negative: Better corner entry

Find the balance that best suits the tune you have.

Adrenaline - how high have you been willing to go with these settings? I have a strange, untested fear of going over 25 in either direction. So much so that I haven't even tried testing it.

 

[tronrider345]

Rear toe:
Positive: Stability, tendency to understeer
Negative: Agility, tendency to oversteer

Front Toe:
Positive: Better corner exit
Negative: Better corner entry

Find the balance that best suits the tune you have.

Thank you a lot!

 

[CSLACR]

Rear toe:
Positive: Stability, tendency to understeer
Negative: Agility, tendency to oversteer

Front Toe:
Positive: Better corner exit
Negative: Better corner entry

Find the balance that best suits the tune you have.

Interesting, I've never read it worded like this...

The only description of front toe I've heard, and thus considered, is how sensitive the steering response is, with quicker response ultimately sacrificing grip. Nothing more.
Example
Positive - Quick response, agile car, poor tire wear and loss of grip at the limits
Negative - Slowed response, car slower (subsequently smoother) in transitions, but with improved tire wear and maximum grip.
(Which I have found true in GT5)

That could explain why I always liked positive front toe on some cars, even if nobody else did.

I'm gonna open a Monza room sometime this evening, anyone's welcome to join. I'll post the number when it's up, probably about 2 hrs from this post. (unless there's one up already then)

Adrenaline - how high have you been willing to go with these settings? I have a strange, untested fear of going over 25 in either direction. So much so that I haven't even tried testing it.

I'm not Adrenaline, but you ought to test it out personally, I recommend that to everyone about everything in tuning.
The most it can hurt is the 15 minutes to try -.50 .75 and .100, etc.

 

[Adrenaline]

Adrenaline - how high have you been willing to go with these settings? I have a strange, untested fear of going over 25 in either direction. So much so that I haven't even tried testing it.

I haven't done extreme settings on anything other than Oval setups, where tire wear can be altered to increase pit strategy at the sacrifice of lap times.

On regular tunes, I rarely go past +/- .10 on the rear and +/- .15 on the front.
My NSX tune is the outlier I believe, but even it only goes to .25. I think the Yellow Bird benefited from extreme settings, but since it's an extreme car, it didn't strike me as odd.

@CSL, as per usual, I won't claim my tuning theories to be correct, but simply what I've found to work, broken down to it's simplest form, based on my personal experience(in GT5). The above was a rather basic form of the way I tune. I start with 0.00 front and back, tune nearly everything else, and then use toe as the final 'balancer' between entry/exit. While the X=Y above is generally a rule of thumb (for me) it's not always that black and white. Everything appears to work on a plateau type path when tuning these small adjustments. Where the plateau can be a range of values that work within reason of eachother, and is a moving target, but as long as you know how and where the drop off occurs, as well as which way said drop off exists, that's all that really matters.

 

[ugabugaz]

I have some news regarding 2 Cars in the 625PP Class. Both cars tested on Monza

1) ZR1 RM - After a good 1/2 hr tuning session I managed to get the car down to a 1:41.3XX with consistent laps. Tested on a ZR1 with Stage 3 Engine.

2) Gillet Vertigo - This car should be banned. Got a 36 on my first lap out, A messy lap too.


My 2 cents for high toe. Use it if needed. My recent YB Touge tune makes huge use of rear toe for stability and subsequent opposite toe for quicker reactions up front. Link is below (Purple)

Toe Angle: -0.38/+1.00

 

[CSLACR]

Except -0.38 front toe makes the reactions slower up front. +1.00 also makes the reactions slower up front, essentially.
At least that's the general consensus of the people I hear talk about it, myself included.

https://www.gtplanet.net/forum/showthread.php?p=5934246#post5934246

 

[ugabugaz]

Perhaps you're right, perhaps not. In my experience with the YB, it felt right going negative up front. Without negative front, the car would refuse to enter corners and would more or less plow - but the back would be very stable. Sticking the negative up front allowed the car to corner as if it didn't have the +1.00 rear toe while still maintaining the rear end stability.

 

[XDesperado67]

Figured out the problem I was having last night...was a rather surprising find for me, but then I don't generally tune cars with a lot of aero. During testing last night was running max front aero and close to minimum rear. After changing to minimum front and increasing the rear the problem all but disappeared. Apparently the front aero was creating so much downforce and acting as a wind brake that it just yanked the front of the car around without enough rear aero to ballance it out. trying to find a good balance of from front aero, rear aero and maximum power for the car on Monza now.👍👍

@Ugabugaz the Gillet is broken. Just pulled the one I have up that I had previously messed about with. The PP is all wonky on the car. With aero set to default and power limiter at 100% with the stock turbo the car is listed as having 664PP. Putting the High RPM turbo on the car which increases both HP and torque changes the PP to 650. Playing with the power limiter the PP actually goes up with some power limiting applied before it starts to go back down.
Mine with stock setttings needs 51% power limiter to get down to 625PP.

 

[ugabugaz]

Interesting! Yeah too much front and not enough rear tends to make the rear sort of..float around imo.

 

[Ronald6]

I enjoy finding better driving lines through a course, and trying to hold the car to that line. Monza is pretty much irrelevant as far as driving lines go. The line is obvious and doesn't change any measurable amount depending on the car you're driving.

On Nordy my driving line changes a great deal depending on the car I'm driving and finding the perfect line is a challenge for the best driver and staying on the line even more of a challenge. I prefer complexes over simple corners, they offer more of a challenge and offer more opportunities for overtaking while racing.

Monza is like NASCAR. Not much point to it.

Edit: post two pages too late. Sorry.

 

[CSLACR]

I enjoy finding better driving lines through a course, and trying to hold the car to that line. Monza is pretty much irrelevant as far as driving lines go. The line is obvious and doesn't change any measurable amount depending on the car you're driving.

On Nordy my driving line changes a great deal depending on the car I'm driving and finding the perfect line is a challenge for the best driver and staying on the line even more of a challenge. I prefer complexes over simple corners, they offer more of a challenge and offer more opportunities for overtaking while racing.

Monza is like NASCAR. Not much point to it.

Edit: post two pages too late. Sorry.

For the record, I use the same lines regardless of the car on every track I can think of offhand, Nurb included.

 

[Ridox2JZGTE]

Having positive toe for me, works best with FF cars and any cars that's tuned for mainly slower speed tracks with numerous tight corners ( Eiger Short or any touge style custom track ). My tunes linked on my sig uses extreme toes, one have both in huge negatives and the other have front +/ rear -. Toe alone can change the way the car behaves when entering and exiting a corner. It can also make the car unstable at high speed.

If anyone curious, try to apply my suspension tune of my R33 GTR Hosaka Tuning linked on my sig, drive the car at Eiger, London, Tsukuba, Nurb, then Monza. The car has toe values unlike most tunes on GTP, but it works for what it was made for - Touge Showdown at Eiger.

Now most of my tune follow similar toe arrangement on various levels, depend on the drivetrain, power and tracks. It gives better response, turn in and grip at the expense of a bit of instability.

 

[Johnnypenso]

Dodge Viper GTS-R Team Oreca Race Car '00

I'd like to enter the 625PP fray with this car. It's the best sounding of the bunch along with the Ford GT's but they're already pretty popular. I might also enter the 500pp event just not familiar with a lot of the cars so I'll have to drive a few to get the hang of the pace with them.

Sorry if this was asked and answered, but are both cars going on both tracks or is it one car per track?