Spa Eau Rouge flat out??

[Kek700]

With mediums I need to lift just a bit when turning left at bottom hill...
I don't say it isn't possible to do flat out with mediums but not with my setup though. With softs it goes quite easily flat out ;-)

I have already asked this so I apologize for that.

With "softs" I still cannot take it flat out.
I have tried every approach. Tried turning in at the bottom in an exaggerated way.
Tried pushing over the right curb half way up which just upsets the car.
Tried straight lining it from the bottom to top.

cutting the corner illegally at the bottom or illegally cut the corner at the top or at run wide
at the last bit of the track, which I can manage, but obviously that's a No Go.
.

It seems every man and his dog takes it flat out on YouTube

 

[Kek700]

Travelling through France at the moment, so not able to send setup. But I will try and describe:-

Front:- ( bound set higher than normal for Eau Rouge to try and stop bottoming out !!! )
Ride height 56-58mm
Front springs 143 to 153 N/mm front.
Depends on softs or medium
Dampers :- rebound 8 bound 5
Fast rebound 11 Fast bound 1 or 0
toe -0.05
ARB 3
Camber -2.7

Rear:-
Rear ride height 5mm above front
Rear springs 130N/mm
Dampers bound 2 rebound 8
Fast bound 0 rebound 11
ARB 4
Toe 0.05
Camber -1.2
Diff:-
Coast 35 ( running this higher inhibits turn in )
Although for running flat out though Eau Rouge
It is pretty meaningless.
Abs 5
Traction 4
Tyres “soft” pressures 26psi arriving at Eau Rouge.
Aero 5
Take 10 mm off suspension travel ( this may be a mistake)!!! Tempted to add 10mm
This setting I have always found confusing.
( unless there is a good reason to ride bump stops )!!
Running kerbs under power has always been problematic for the GTr, so I never run raised kerbs.
Not true for coasting some raised kerbs.

That’s as much as I can remember.

 

[RasmusP]

Take 10 mm off suspension travel ( this may be a mistake)!!! Tempted to add 10mm
This setting I have always found confusing.
( unless there is a good reason to ride bump stops )!!

Front springs 143 to 153 N/mm front.

( bound set higher than normal for Eau Rouge to try and stop bottoming out !!! )

In theory, only in theory as I don't really know the car and can't test it for real at the moment:
You could try to shift the setup into:
- lower front spring
- lower front bump
- maybe even lower the front height

And then put as much packer in it until you don't bottom out anymore. This will result in a little knock when going into the compression as you'll hit the packers.
But in theory you can use this to be able to drive a setup that wouldn't be possible without "travel restrictors".
Also some cars tend to "stall" their aero if you go too low. Might be worth to check if the Nissan does that and therefore understeers. Restriction the suspension travel might be the thing to go for then!
Sadly this data isn't written into telemetry and not in the replay so you have to record your real time driving and then check the values..

You know what? I'll just do that quickly via mouse steering

 

[Kek700]

Front ride height is as low as it can go
and it does not cause stalling.
Have tried lower bump, increased it for Eau Rouge.
As you have already said to me, I need to
use ATCI when I get back home.
GTr does not allow packers only height adjustment.

 

[Richard Dastardly]

Generally I don't think GT3s really need 5 wing, especially on a fast track like Spa. I don't usually do my own complete setups but if I'm modifying one for a fast track I will most of the time go with the philosophy of reducing rear wing until I can't practically soften the rear of the car anymore. The quick test on the GT-R I did was with 3 wing, and that was perfectly driveable. Admittedly I ended up with rear ARB on 0 by that point because I had to add spring.

Reducing rear travel would probably have been more sensible, after some thought ( although again there were benefits in other fast corners ) - probably have to stay off the kerb at Stavelot ( I suspect you really should & my crashing over that is a bad hablt ) & Les Combes might get exciting. I wouldn't worry about scraping the splitter up Radillon, start caring when the car starts lunging left because it's lost traction.

 

[Pawel Ziolkowski]

@Kek700 Oh so you didn't touch packers ? That's like the main thing to tinker with to make the car behave at eau rouge while not destroying setup for the rest of the lap
Generally you want to balance ride height against packers so that you have the least amount of front left packers (highest height) that allows both smooth aerodynamics and no significant scraping (there is a grip sweetspot usually) which for eau rouge will still be quite a bit.
Rear left packers are also good to reduce understeer in right turn compression, so dial as much as possible (lowest) without significant impact to balance in other corners.

Also running higher fast bump and lower fast rebound should give some more grip on entry (left kerb) and in right turn compression section.
I'd recommended 0-2 bump 5-10 fast bump, some high-ish rebound and 0-2 fast rebound - that's for FL wheel, FR you'd be fine with lower fast bump and higher fast rebound

As for ride height, GTR likes to run as low as possible. You can go too low in eau rouge but the point where splitter gives up usually coincidences with severe scrapping so it's easy to spot. Bigger issue would be to have too high ride height so the splitter stalls at the top.

Running raised kerbs is tricky in GTR... in other cars using less front camber and more rear camber helps, but the way GTR is designed, it's not that helpful. So it's down to driver mostly in this regard.
But if you mentioned live values in the setup, tinkering with cambers might still be of use. For comparison I'm using only 2.0 front and 1.6 rear. With different springs/ARB it's not directly comparable, but it seems your values might be on the "unstable" side.

edit: The last "trick" for GTR is to use asymmetric ride height, give left side 2-3 mm more and take the same out of right side. It's not "significant" but can help a small bit.

 

[RasmusP]

Front ride height is as low as it can go
and it does not cause stalling.
Have tried lower bump, increased it for Eau Rouge.
As you have already said to me, I need to
use ATCI when I get back home.
GTr does not allow packers only height adjustment.

I threw in your setup. Here are telemetry and live video results:

Ride Height FL: (min 16.8mm)

Dampers:
Ratios:

Normal:

Fast-Dampers:

Camber at highest G-Force:

Not really big of a clue what to do with it but I guess you got 16mm spare, should try to even out the dampers, lower the camber and try again!

 

[Pawel Ziolkowski]

Generally I don't think GT3s really need 5 wing, especially on a fast track like Spa. I don't usually do my own complete setups but if I'm modifying one for a fast track I will most of the time go with the philosophy of reducing rear wing until I can't practically soften the rear of the car anymore. The quick test on the GT-R I did was with 3 wing, and that was perfectly driveable. Admittedly I ended up with rear ARB on 0 by that point because I had to add spring.

Looking at RSR laptimes and top speeds the wr was done on 5 wing. Not saying 2-3 wing is bad, but GTR is pretty efficient up to 5-6 wing so the laptime difference to 2-3 should be very small i think.

 

[Kek700]

Looking at RSR laptimes and top speeds the wr was done on 5 wing. Not saying 2-3 wing is bad, but GTR is pretty efficient up to 5-6 wing so the laptime difference to 2-3 should be very small i think.

Good to read that, exactly the conclusion I
have come too

Rasmus
there does not seem to be much
to worry about from your graphs the fast
Bump dampers are a bit one sided for the rest of the circuit, but probably ok for Eau Rouge.
Also camber does not have much effect
at Eau Rouge as there is not that much
Lateral g force, Note I also run camber settings
from the main setup screen and not the bar
thingy.
It all happens at the turn in at Eau Rouge,
if it would instantly turn right there I could drive
the rest easily. The lift, just there,gives the
car that immediate turn in.
I could be confused

Pawel
I did not think there are packers on
my setup just height before bump stops
are engaged. Maybe that’s what you mean.

The unsymmetrical setup could make
sense at Eau Rouge because there is a
quick weight transfer taking place there!!
Will try that when I get home.
Including a change to dampers as well this
may be a better thing to try first.

As I said before, for me there is probably
2 to 3 tens here for me, it is probably due
to the GTr being very torquey and drives strongly
up the hill even with a slight lift at the bottom of the hill. Just a guess.

 

[RasmusP]

I also run camber settings
from the main setup screen and not the bar
thingy.

Oops. Then forget about the camber graphs!
Rest only made sense when looking at the real data sheet, but camber is set in the left bars..

 

[Pawel Ziolkowski]

I did not think there are packers on
my setup just height before bump stops
are engaged. Maybe that’s what you mean.

Ah yes, it's "travel range" ... AC confuses me a bit here. On gt3 cars the stiffness of these travel stops is close to springs, so they effectively work like packers (also in setup file they are called packers).

As I said before, for me there is probably
2 to 3 tens here for me, it is probably due
to the GTr being very torquey and drives strongly
up the hill even with a slight lift at the bottom of the hill. Just a guess.

Don't push it too hard to go flat out, if you succeed "barely" (on the limit of adhesion till the top of the hill) it would still be faster to lift at the bottom instead and have smoother climb.

 

[Richard Dastardly]

Looking at RSR laptimes and top speeds the wr was done on 5 wing. Not saying 2-3 wing is bad, but GTR is pretty efficient up to 5-6 wing so the laptime difference to 2-3 should be very small i think.

Yeah, I guess so - the aero balance was really nice on that setup with 3 wing though. I'm gonna echo the advice that it might be quicker to lift at the foot, you don't want to be scrubbing in the middle of Radillon & especially not at the top.

I guess this is a suitable place to ask if anyone has a favourite guide to starting with motec in their bookmarks?

 

[RasmusP]

I guess this is a suitable place to ask if anyone has a favourite guide to starting with motec in their bookmarks?

There are some video tutorials but in the end it's soooo much time you'd spend with things you don't need.
The quickest thing is to download acti, follow the instructions there and then I'll send you my workspace.
Back it up as changes are instantly auto saved and not really reversible and then click around and mouse-over everything.
I can surely write up a quick start guide about important hotkeys and functions.

 

[Richard Dastardly]

There are some video tutorials but in the end it's soooo much time you'd spend with things you don't need.

Yeah, I know how these things go, hence the ask...

The quickest thing is to download acti, follow the instructions there and then I'll send you my workspace.
Back it up as changes are instantly auto saved and not really reversible and then click around and mouse-over everything.
I can surely write up a quick start guide about important hotkeys and functions.

Acti/motec has been installed & functional for years - I occasionally import some telemetry & have a look at it, but I've never been sufficiently interested to fight a brand new UI - a workspace & important features guide is pretty much exactly what I'm after, thanks.