iRacing 24 Hours of Spa

[Bedo]

Whatever you guys feel comfortable with, map setting is very subtle. If you have any issues with the setup, pushing, oversteer, lockup, let me know, and i can try to fix.

Btw, on real spa first 6 cars are AMGs!

 

[Nejtun]

The mercs did kinda cheat in qually with their hax ECU's though , but 1 of them is back in the top ten after their 2 laps penalty

 

[Noodleguitar]

I've edited Kyle's set somewhat. I've gotten rid of the track-out oversteer and it still seems to turn in pretty well.

Keep in mind I've set my brake bias, ABS and TC to personal preference.

Thanks for sharing a set with us Bedo. I'll have to try it out later, so many sets to try!

 

[Daunt]

Wanted to do full stint tests but held off to do more setup testing. I like your set a lot Noel. Stable and pretty fast. Tire pressures are spot on. Better turn in than my set but I think it's sacrificing on mid corner understeer.

I was having a lot of issues with pushing on track out which is shitty at Spa and I have to imagine it will be terrible in draft. Maybe it's just me or my driving style. But Midcorner oversteer might be much worse here at Spa than a less than a bad turn in. Eau Rouge was also tricky but not deadly... just not necessarily as comfortable as it was.

So I decided to try and help with the mid corner understeer. I softened the front ARB by one... this created minor oversteer issues on exit, as somewhat expected, so I increased the wing. For me, I was able to lower my OPT by quite a bit and hit into the 21s much more often.

My optimal was 2:21.304. My best lap was 2:21.642 (with my adjusted set) I believe you lose 1-2 KPH on the end of the Kimmel straight. With your set Noel I was doing 258 I think. And with mine I could hit 156/157.

I've also adjusted TC/BB to my own preference for the attached.

 

[Nejtun]

We were questioning in TS the other day if double stinting the tyres was a good or bad idea , the winner of this evenings BES started last (BMW) Formel1frede.( Fredrick Rasmussen)

I know we also said it was probably only the BMW that was kind enough to its tyres, but with 35 seconds saved every two pits stops this has to be worth thinking about, also as the tyres get changed one at a time, changing one or two tyres instead of all four might be worth considering?

Just info, thought it might be worth sharing

 

[Noodleguitar]

Kyle's set feels pretty good right now.

Double stinting tires on the Mercedes is probably not a good idea, as you can see below. It can work on the BMW but the Mercedes is rough on the tires and I was easily losing 1+ second per lap before the end of a stint.

 

[Daunt]

Nice info Noel. The time fall off is very real so it will be more about being consistent than overall speed. I assume you got good fuel data and pitting data?

 

[Nejtun]

Checked the BMW for myself so you can get a comparison.
the tyres started getting a bit squishy towards the end of the stint but nothing that couldn't be driven around. my lap times slowed a little but i think more of it was to do with me getting a bit bored and starting this at 7 am .
The weather was very nice. just used the BES practice session so I had no control over this.

Rear tyres felt very good at the end , the fronts were suffering a bit running brake bias at 52%.

 

[Daunt]

Yeah the difference in temperature from what we're running (Default) is huge. Close to 20 degrees in track temp. I'd be more inclined to think you'd be closer to Noel's wear percentages if you went default but I'm not really sure though because the default weather is just that much worse.

Overall one of the major differences is driver experience and comfort. One spin over the course of that second stint is all it takes to completely negate taking tires. With solid drivers I'd say its viable but I don't trust myself enough. I still think though iRacing in general though isn't set up like RL when it comes to tires and how long they last. Maybe with the upcoming NTM7 we'll see. But Dave K (iRacing Dev) insists tire wear is pretty accurate. He goes into great detail here regarding tire temps, wear, and such in sim: http://members.iracing.com/jforum/posts/list/1808602.page#3728601

 

[Daunt]

Kyle's set feels pretty good right now.

Double stinting tires on the Mercedes is probably not a good idea, as you can see below. It can work on the BMW but the Mercedes is rough on the tires and I was easily losing 1+ second per lap before the end of a stint.

View attachment 3132

Noel you think we should take a look at the rear camber? That's quite a significant difference in wear percentages on the rear.

 

[Noodleguitar]

Noel you think we should take a look at the rear camber? That's quite a significant difference in wear percentages on the rear.

Maybe, but the difference in wear between outside and the middle/inside is not hugely more than the fronts. I think currently the rear camber is around 1.6-1.8 (can't remember if that's + or - ) which doesn't seem ridiculous but we can always try a lower value.

I have only checked the fuel usage so far. I got 1.770 L/min (including pit-in), Nejtun got something very close to that as well. Kyle, I'm not sure how you manage to get 1.8+

 

[Noodleguitar]

Also, the pressures and temperatures at the end of my stint seemed a little low, but that could well be because the tires were allowed to cool down in the pit lane of over a minute.

 

[Daunt]

I have only checked the fuel usage so far. I got 1.770 L/min (including pit-in), Nejtun got something very close to that as well. Kyle, I'm not sure how you manage to get 1.8+

I'll try a slight camber adjustment but nothing major. It could also be my stint was not even a half stint, as I'd use less fuel for that second half and so didn't get the numbers for it.

 

[Daunt]

I have only checked the fuel usage so far. I got 1.770 L/min (including pit-in), Nejtun got something very close to that as well. Kyle, I'm not sure how you manage to get 1.8+

How many laps did you manage?

 

[Daunt]

FYI - Default Weather & LATE AFTERNOON

I've updated the OP with a better, revised spreadsheet (uses google docs). No new information though, everything remained the same.

 

[Noodleguitar]

Oh for fuck's sake . Now the testing we have done so far is not that accurate anymore. Well, at least there will be a lot more grip, which I prefer. We might be able to click the wing down 1 notch.

In my stint I managed 29 laps but I had to save some fuel on the last lap to be able to do it (might also be why my fuel usage per minute is fairly low). I entered the pit box with 0.1 L left after I realized that the entire pit lane also takes up 0.5 L of fuel.

 

[Daunt]

Oh for fuck's sake . Now the testing we have done so far is not that accurate anymore. Well, at least there will be a lot more grip, which I prefer. We might be able to click the wing down 1 notch.

In my stint I managed 29 laps but I had to save some fuel on the last lap to be able to do it (might also be why my fuel usage per minute is fairly low). I entered the pit box with 0.1 L left after I realized that the entire pit lane also takes up 0.5 L of fuel.

Yeah we'll have to do some more testing but practice is good anyhow. I'm happy as well, as it will make the second half of the stint much safer. I agree on the wing, we'll have to try that.

So 28 is a pretty good estimate and I'm going to stick with that. Fuel saving for 29 doesn't seem like fun... haha. In any case, I have 24 stints on the schedule but honestly I'll probably lose one ish at the end... with stints being around 65-70 minutes we should only need 22 stints, not 24. I'm going to adjust the schedule for 65 minute stints... not exact still but closer... so your time slots may shift slighty while my final stints may move / coalesce into Noel's last stint. I'm not sure yet.

 

[Noodleguitar]

Late afternoon is really a big difference. I clicked the wing down to 3 and raised the tire pressures. I've attached the new setup. There is still some tire fall-off but not nearly as severe as in afternoon weather, see below:

 

[Daunt]

Completed a full stint- used 4.232 / lap or 1.834 / min. Was in the car for about 1:05 so that's a good estimate.

 

[Noodleguitar]

Here is the Fuel Chart.

As you said, 22 stints works out well. Even if we're running 2:19s on average we can still easily do 22 stints. With the current estimate our last stint is about half an hour when taking a full tank every time. If we take 115 L on each stop we mix up 27 and 28 lap stints which could be a little easier on the tires. If there is traffic/draft I could possibly do a 29 lap stint if it would help.

I've set the fuel usage to 1.8, since I was using 1.78 and you are using 1.83.