AC DRM Revival @ Feldbergring - Wed 14 Aug 2019

Victor M Fernandez · Aug 18, 2019

Bobby Pennington said:
What @Ronnie Böhme put up should help you a lot. Keep in mind that there is no shortcut to this stuff. It comes with experience and a lot of reading and then trial and error while in practice sessions. It's all I did for years and years since the bots were all I raced and doing hotlaps trying to squeeze out a tenth or 2 here and there.

I'll give you a couple of routes to pursue Jeroen.

Remember this: If you're a mid packer like me, I have to maximize everything I can before my car hits the track. That's the stuff that all of us can control and you don't have to be an to do that, so pay attention to the little details like your tires and gearing.

Cars with no adjustable aero:

Always take a new car out using the stock setup on a track and run it until you can get within .200 - .300 a lap in consistency. If you don't, you'll never know if it's your driving or the car.

Get your tire compound and psi's correct. I recommend getting the proTyre app if you don't have it. Read how to use it. It's very clever.

Gearing- You want the car to be almost on the rev limiter 3/4 the way down the longest straight. I like to leave a little overhead for my race setup so, if I have an opportunity to catch a tow, I don't run out of gear and can't make the pass.....that suuuuucks The easiest way to do this is use the Final Drive ratio. Then you can tweak it from there with the individual gears. Individual gearing can be a little tricky. If you have to much of a gap between gears, your rpms will drop to low and take you longer to reach your shift point in a gear. If you have to little, you're not taking advantage of the torque and bhp curve and your constantly shifting. Each upshift can cost you a fraction of time so, if you're upshifting 10 times to many per lap, it adds up.

Electronics if the car has them. In AC a setting of 1 is where the computer has more control so the higher the number, the more you have control.

Got that stuff sorted now so we go to spring rates and anti roll bars (ARB). Work with one first and if it feels ok, work with the other one to see how they feel together. Softer in both areas typically means more grip, but it also allows more body roll which makes for a sluggish responding car. Stiffer in both areas typically means less grip, but a much more responsive car to the point of nervousness. Different tracks also respond to soft or stiff. I find a stiffer car at Mugello and Spa make me quicker at those tracks.

Ride Height - In most cases we want the front of the car to be a little lower than the rear. This is know as Rake Angle. A lower front end will put more weight on the front axle and will help with corner turn in, but it's a dynamic number because we are braking sometimes when we are turning in. Feel will be your guide here. The lower the car, the lower the CG (center of gravity) which means a little less car lean which is ideal, but get it to low and you'll have road bumps and curb issues with the car bottoming out and you can also run out of suspension travel which means you are relying entirely on the tire for grip AND suspension. Go practice at Spa and go through Eau Rouge and you'll see what I mean. Go to Imola to see how your car reacts over some of those mountainous curbs....you'll be a skateboarder grinding the lip Typically you'll have to come back to ride height as you further refine your setup.

Diff Power and Coast. Diff Power- the higher the number the more traction coming out of the corners at the risk of spinning out if you give it to much boot. You can use TC along with diff power to reach a good compromise. Diff Coast- the higher the number the more stable on corner entry (off throttle) but the car will be harder to turn and will push. The lower the number the easier the car will turn in, but can make the car very loose on turn in. Use brake bias and ABS to find a compromise.

Brake bias plays a big part in how a car slows down and rotates on corner entry. Get it wrong and you either crash into the tree you're looking at or you'll back into it and go up in flames

Toe adjustment front and back. Negative toe in the back can kill you on corner entry so be careful with it. Toe also affects tire temps and wear. Use the flow chart Ronnie provided.

Now the Black Art: Dampers. These are your fine tuning points once you have a good setup on the 9 areas listed above. Slow bump and slow rebound are about driver inputs. They make a difference on steering, traction under throttle and braking. Fast bump and fast rebound are about how the car handles things like bumps, curbs etc. They do have an overall affect on how your car feels in certain situations, but you have to be careful it's not your spring rates causing you issues.

Camber- I always do this last because the above 10 steps will have an affect on camber. We will always run 0 - Negative Camber (tires leaning in toward car center line) to maximize tire contact patch in corners as we lean on the tire. You want a temp differential of 7-11 degrees from the inside shoulder (always runs hotter) to the outside shoulder (always runs cooler). Front camber helps with corner entry and grip through the corner. Rear camber helps with corner entry with braking and corner exit with traction. You can see how the temps are with a color code in the proTyre app if you have it visible. Green is good, orange and red are hot and blue is cold. Without telemetry it's hard to tell how the tire does in a certain section, but it's sim racing and not life or death. Coloring with Crayons is good enough for us older kids

See how it's all coming together? Take care of the big (macro) stuff first and the small (micro) stuff later. Now we tweak to find compromise and car feel. I don't care what numbers are right or wrong, if the car doesn't feel good to you, you won't be able to drive it on the limit. Make adjustment on 1 thing at a time while learning, but sometimes you can get away with 2 and that's about it. Example: Car is loose on corner entry so you might try softening the rear slow rebound and by one or two clicks and add a click or two of brake bias to the front.

Cars with adjustable aero:

Always take a new car out using the stock setup on a track and run it until you can get within .200 - .300 a lap in consistency. If you don't, you'll never know if it's your driving or the car.

Get your tire compound and psi's correct. I recommend getting the proTyre app if you don't have it. Read how to use it. It's very clever.

Gearing- You want the car to be almost on the rev limiter 3/4 the way down the longest straight. I like to leave a little overhead for my race setup so, if I have an opportunity to catch a tow, I don't run out of gear and can't make the pass.....that suuuuucks The easiest way to do this is use the Final Drive ratio. Then you can tweak it from there with the individual gears. Individual gearing can be a little tricky. If you have to much of a gap between gears, your rpms will drop to low and take you longer to reach your shift point in a gear. If you have to little, you're not taking advantage of the torque and bhp curve and your constantly shifting. Each upshift can cost you a fraction of time so, if you're upshifting 10 times to many per lap, it adds up.

Aero - As greedy ham fisted drivers, we always want as much grip up front as we can get while at the same time running as little wing in the back so we maximize speed, limit fuel consumption and reduce understeer Get it right and it's a thing of beauty. Get it wrong......mushroom cloud going through Eau Rouge at Spa. Balance is the key. Find what works now and then you'll have to go back to gearing because rear wing has a big influence on top speed. You will also revisit aero once you go through the rest of the setup below. This is where we can work with less rear wing and still stabilize the car through suspension settings.

Electronics if the car has them. In AC a setting of 1 is where the computer has more control so the higher the number, the more you have control.

Got that stuff sorted now so we go to spring rates and anti roll bars (ARB). Work with one first and if it feels ok, work with the other one to see how they feel together. Softer in both areas typically means more grip, but it also allows more body roll which makes for a sluggish responding car. Stiffer in both areas typically means less grip, but a much more responsive car to the point of nervousness. Different tracks also respond to soft or stiff. I find a stiffer car at Mugello and Spa make me quicker at those tracks.

Ride Height - In most cases we want the front of the car to be a little lower than the rear. This is know as Rake Angle. A lower front end will put more weight on the front axle and will help with corner turn in, but it's a dynamic number because we are braking sometimes when we are turning in. Feel will be your guide here. You also have to keep in mind that Aero pushes the car down so, if you put more aero on, you'll either have to raise the ride height a little or stiffen the spring rates and the opposite if you take aero off. Car ride height also affects what we call "Ground Effect". Ground Effect is how the air flows under the car from the front wing/splitter all the way to the back of the car where the diffuser is and creates a suction to the track by lowering the air pressure under the car. If the car is to low, not enough air flows under the car and you "stall" the ground effect. If the car is to high, you cannot create the lower air pressure and it's just as bad as having the car to low. If you have the front ride height correct and the rear is to high, the car will be loose at the rear. Rear wing can overcome this, but remember, you're a greedy head full of rocks driver so we typically won't do this. If the front is to high, the car will want to push, but, BUT you can sometimes run a click less rear wing you greedy bast!!! You'll get the hang of it......eventually Telemetry is the best way to do this, but it's also overwhelming and I just don't think you need to deal with to much right now. Just look at the stock ride heights in the "Car Status" area when your in the setup section and use that as a base and don't deviate to far from it. + or - .10 is what I used to use. The lower the car, the lower the CG (center of gravity) which means a little less car lean which is ideal, but get it to low and you'll have road bumps and curb issues with the car bottoming out and you can also run out of suspension travel which means you are relying entirely on the tire for grip AND suspension. Go practice at Spa and go through Eau Rouge and you'll see what I mean. Go to Imola to see how your car reacts over some of those mountainous curbs....you'll be a skateboarder grinding the lip Typically you'll have to come back to ride height as you further refine your setup.

Diff Power and Coast. Diff Power- the higher the number the more traction coming out of the corners at the risk of spinning out if you give it to much boot. You can use TC along with diff power to reach a good compromise. Diff Coast- the higher the number the more stable on corner entry (off throttle) but the car will be harder to turn and will push. The lower the number the easier the car will turn in, but can make the car very loose on turn in. Use brake bias and ABS to find a compromise.

Brake bias plays a big part in how a car slows down and rotates on corner entry. Get it wrong and you either crash into the tree you're looking at or you'll back into it and go up in flames

Toe adjustment front and back. Negative toe in the back can kill you on corner entry so be careful with it. Toe also affects tire temps and wear. Use the flow chart Ronnie provided.

Now the Black Art: Dampers. These are your fine tuning points once you have a good setup on the 10 areas listed above. Slow bump and slow rebound are about driver inputs. They make a difference on steering, traction under throttle and braking. Fast bump and fast rebound are about how the car handles things like bumps, curbs etc. They do have an overall affect on how your car feels in certain situations, but you have to be careful it's not your spring rates causing you issues.

Camber- I always do this last because the above 11 steps will have an affect on camber. We will always run 0 to Negative Camber numbers (tires leaning in toward car center line) to maximize tire contact patch in corners as we lean on the tire. You want a temp differential of about 7-11 degrees from the inside shoulder (always runs hotter) to the outside shoulder (always runs cooler). Front camber helps with corner entry and grip through the corner. Rear camber helps with corner entry with braking and corner exit with traction. You can see how the temps are with a color code in the proTyre app if you have it visible. Green is good, orange and red are hot and blue is cold. Without telemetry it's hard to tell how the tire does in a certain section, but it's sim racing and not life or death. Coloring with Crayons is good enough for us older kids

See how it's all coming together? Take care of the big (macro) stuff first and the small (micro) stuff later. Now we tweak to find compromise and car feel. I don't care what numbers are right or wrong, if the car doesn't feel good to you, you won't be able to drive it on the limit. Make adjustment on 1 thing at a time while learning, but sometimes you can get away with 2 and that's about it. Example: Car is loose on corner entry so you might try softening the rear slow rebound and by one or two clicks and add a click or two of brake bias to the front.

One thing you'll notice in the "Car Status" in AC is camber, toe angle can be different on each corner of the car in the pits and flicker and ride height will vary from pit box to pit box. The tracks are laser scanned so we don't always have a perfectly level surface. A trick I learned from a friend is to go to the drag strip after you've finished your setup to see if the numbers are what you're looking for. It's a perfectly level surface.

Car stiffness will have an affect on tire temps. Usually, a softer setup or setting will generate more tire carcass heat and you can see a tire load up with heat while driving if you have the tire app on screen. Stiffer settings typically create surface heat across the tire contact patch and you can see that if you have the proTyre app visible. You can tweak both of these for longer races where you are concerned about limiting pit stops or getting away with no tire change and do a splash and dash. Sprint races, smoke 'em if you got 'em Go out and paint the town red

This is my approach. I'm not an expert, not the quickest, but I do have a decent understanding of this mumbo jumbo. Like I said, it's overwhelming at first, but you'll get it. I'm sure some guys will probably disagree with me and they may or may not be correct. I'm also sure I've probably left something out and if I have, I hope someone catches it.

Have fun with this stuff and don't sweat it. Enjoy the journey and remember, at the end of the day, we're just moving pixels on a screen and not paying our bills with it. If you do that you'll keep your sanity and your hair. Well, you could still lose your hair due to genetics, but I don't think we need to go into that

JeroenH · Aug 18, 2019

Bobby Pennington said:
What @Ronnie Böhme put up should help you a lot. Keep in mind that there is no shortcut to this stuff. It comes with experience and a lot of reading and then trial and error while in practice sessions. It's all I did for years and years since the bots were all I raced and doing hotlaps trying to squeeze out a tenth or 2 here and there.

I'll give you a couple of routes to pursue Jeroen.

Thank you so much! Saving this and I will try to have a good look on it this week. I can't believe how much time you put in to this

In combination with the spreadsheet from @Ronnie Böhme I think I may be getting a hang on the thought process of getting something that works.

Awesome community!

Victor M Fernandez · Aug 18, 2019

Bobby Pennington said:
What @Ronnie Böhme put up should help you a lot. Keep in mind that there is no shortcut to this stuff. It comes with experience and a lot of reading and then trial and error while in practice sessions. It's all I did for years and years since the bots were all I raced and doing hotlaps trying to squeeze out a tenth or 2 here and there.

I'll give you a couple of routes to pursue Jeroen.

Remember this: If you're a mid packer like me, I have to maximize everything I can before my car hits the track. That's the stuff that all of us can control and you don't have to be an to do that, so pay attention to the little details like your tires and gearing.

I really appreciate this post @Bobby Pennington

It has, IMO, a couple pearls in it. I've read many different notes on setting up racing cars, but your contribution is clearer.
I've been struggling with setting up GT3s, now I am starting to see why, though I need to practice and get the feeling for it. I don't think I'll be ready for today's race (GT3 @ VIR), but in the long run it has really helped me. Now, I can follow a proccess of setting up, what to feel for, and the most important part "proTyres manual". It's clear now for me how to understand it, so I can assess if a setup is stiff or soft, and the carcass and core temp. Other material I have, including the helpful and clear flow chart from @Ronnie Böhme, fit into this main stream.
Your kindness and willingness to help other fellow racers out of their despair is utterly appreciated.

Bobby Pennington · Aug 18, 2019

Hey guys, while I was out last night, I thought of a few things I failed to mention in my previous post with the guide. I've shared it over in the forums and here is the link to it. Things like this are always a work in progress, but I think what I added to it is good enough to get you started. I didn't mention bump stops / packers, bump stop / packer rate, bump stop / packer range or travel range. We'll get into that later, but it's pretty simple, but it's a lot of writing. You can watch videos or read other resources with your morning cup of coffee.

Ronnie Böhme · Aug 19, 2019

Bobby Pennington said:
I'll give you a couple of routes to pursue Jeroen.

Remember this: If you're a mid packer like me, I have to maximize everything I can before my car hits the track. That's the stuff that all of us can control and you don't have to be an to do that, so pay attention to the little details like your tires and gearing.

Holy cow Bobby, this is a masterpiece. Absolutely amazing.

Ronnie Böhme · Aug 19, 2019

ChikiWaki said:
So, would you mind trying my setup and see what can you achieve?
The same setup with Slicks, 100% Turbo and 17 Litres allow me a 51.656

I'm sorry to reply that late but I've had a really crazy weekend.

So, I did a few (actually quite a lot) laps with each setup as it is, then with necessary adjustments like tire pressure, because that varies quite a lot with driving style. And then a few with the adjustments that to me seemed necessary.

I went with my own setup first, as a reference and to get into "the flow". I wasn't quite able to challenge my own quali time but got quite close with a 3:45.309

Next was your first setup. It has incredible traction exiting the slow corners and the turn in, especially in the right-hander that drops down a lot, is amazing. Yet at least for my driving style it is too twitchy in mid- and high-speed corners and I was always on the edge of losing it. This was showing in the tire pressures as well as my rears were at +1.2 - +1.5 psi (over the optimal value) all the time. So I fixed that and got a 3:46.001out of it. Since it was still too twitchy for my taste I've tried to fix that too. The main problem in my opinion is the low rear ride height which doesn't allow for enough suspension travel. I've raised it to the max at the rear and lowered it to the min at the front and got a quite predictable setup but couldn’t go any faster. It wasn't slower either, just more stable, thus less work to go fast.

Last was the hybrid which felt completely different, in a good way. I would have taken it as race setup anytime, just as is, but then I noticed I couldn't go fast enough. Despite the great handling I struggled to get into the 46es. So I've tried to find the Problem. First of all I've raised the front tire pressure by one click to keep the value at optimum in the fast right-hander after start / finish and the 3rd gear right-hander at the back"straight" risking a bit of overpressure in the tight turns but that is okay. That was immediately almost a second quicker. So I went for the rake setting again, maximising it as before, this time more for aerodynamic reasons. This made me so fast on the straights, because I could keep the momentum through the fast corners, that I had to raise 6th gear by one klick not to hit the limiter before start / finish. Et voila 3:45.12. After leaving the game ContentManager even told me that I would have theoretically beaten my pole time by almost 3 tenths. So with your permission I'd like to keep that setup if I may.

I hope that helps a little and is somehow what you've hoped / expected from this little experiment.

Victor M Fernandez · Aug 19, 2019

Ronnie Böhme said:
I'm sorry to reply that late but I've had a really crazy weekend.

So, I did a few (actually quite a lot) laps with each setup as it is, then with necessary adjustments like tire pressure, because that varies quite a lot with driving style. And then a few with the adjustments that to me seemed necessary.

I went with my own setup first, as a reference and to get into "the flow". I wasn't quite able to challenge my own quali time but got quite close with a 3:45.309

Next was your first setup. It has incredible traction exiting the slow corners and the turn in, especially in the right-hander that drops down a lot, is amazing. Yet at least for my driving style it is too twitchy in mid- and high-speed corners and I was always on the edge of losing it. This was showing in the tire pressures as well as my rears were at +1.2 - +1.5 psi (over the optimal value) all the time. So I fixed that and got a 3:46.001out of it. Since it was still too twitchy for my taste I've tried to fix that too. The main problem in my opinion is the low rear ride height which doesn't allow for enough suspension travel. I've raised it to the max at the rear and lowered it to the min at the front and got a quite predictable setup but couldn’t go any faster. It wasn't slower either, just more stable, thus less work to go fast.

Last was the hybrid which felt completely different, in a good way. I would have taken it as race setup anytime, just as is, but then I noticed I couldn't go fast enough. Despite the great handling I struggled to get into the 46es. So I've tried to find the Problem. First of all I've raised the front tire pressure by one click to keep the value at optimum in the fast right-hander after start / finish and the 3rd gear right-hander at the back"straight" risking a bit of overpressure in the tight turns but that is okay. That was immediately almost a second quicker. So I went for the rake setting again, maximising it as before, this time more for aerodynamic reasons. This made me so fast on the straights, because I could keep the momentum through the fast corners, that I had to raise 6th gear by one klick not to hit the limiter before start / finish. Et voila 3:45.12. After leaving the game ContentManager even told me that I would have theoretically beaten my pole time by almost 3 tenths. So with your permission I'd like to keep that setup if I may.

I hope that helps a little and is somehow what you've hoped / expected from this little experiment.

First of all I would like to appreciate the time you spent on this experiment.

No worries about the delayed response, I know you have your "stuff" going on.

Yes, indeed it helps me a lot.

The 1st setup is just too nervous in the mid-high speed corner. Very stable braking and slopes, and as you pointed out, amazing acceleration. Rising the rear and lowering the front really makes it very stable, less stressful to drive. But as you said, no difference in time, so better a more trustworthy setup.

Hybrid, the idea behind keeping the negative rake is that allows for more changes in the setup, in case a need to twitch it a tad, highest rear and lowest rear (keeping the lowest possible negative rack) doesn't allow much tunning. But as you has shown me, there are many other ways of keep tunning the car.

So 1 more click on front tyre pressure, true, that makes the tyre pressure to be optimum at those critical turns you mention, and the overpressure in the slow corners is not that important. Lesson learnt.

Definitely better the lowest negative rake possible, in terms of "confidence" on the front end of the car. I've learn to deal with the light front, but I don't like at all.

And lastly, one higher 6th gear, awesome. I'd already added one more click to your 6th gear. So now we have a very high-speed-end-of-the-straight car.

Of course you can keep it and use it freely, it's your setup! If you don't mind, I also would like to use it

You know that I cannot even get close to 1sec diff. with respect to your raw speed.

My goal is to be within 1.5 to less than 2.0 delta from your time, tops.

Again Ronnie, I really appreciate the time you've dedicated to my quest for knowledge.

Ronnie Böhme · Aug 19, 2019

ChikiWaki said:
First of all I would like to appreciate the time you spent on this experiment. No worries about the delayed response, I know you have your "stuff" going on.

Yes, indeed it helps me a lot.

The 1st setup is just too nervous in the mid-high speed corner. Very stable braking and slopes, and as you pointed out, amazing acceleration. Rising the rear and lowering the front really makes it very stable, less stressful to drive. But as you said, no difference in time, so better a more trustworthy setup.
Hybrid, the idea behind keeping the negative rack is that allows for more changes in the setup, in case a need to twitch it a tad, highest rear and lowest rear (keeping the lowest possible negative rack) doesn't allow much tunning. But as you has shown me, there are many other ways of keep tunning the car.
So 1 more click on front tyre pressure, true, that makes the tyre pressure to be optimum at those critical turns you mention, and the overpressure in the slow corners is not that important. Lesson learnt.
Definitely better the lowest negative rack possible, in terms of "confidence" on the front end of the car. I've learn to deal with the light front, but I don't like at all.
And lastly, one higher 6th gear, awesome. I'd already added one more click to your 6th gear. So now we have a very high-speed-end-of-the-straight car.
Of course you can keep it and use it freely, it's your setup! If you don't mind, I also would like to use it You know that I cannot even get close to 1sec diff. with respect to your raw speed.
My goal is to be within 1.5 to less than 2.0 delta, tops.
Again Ronnie, I really appreciate the time you've dedicated to my quest for knowledge.

You are very welcome and of course you can use the setup whenever and wherever you like.
One last word on the rake thing. You are absolutely right about limiting your setup options by going to extremes. But this car is special in that department. I've never seen (or noticed) that much negative rake at any car, usually I go for around 10mm to 20mm with a GT3 car for example and only very occasionally with extremes, depending on the possibilities of the setup.

Bobby Pennington · Aug 19, 2019

Ronnie Böhme said:
Holy cow Bobby, this is a masterpiece. Absolutely amazing.

Thank you Ronnie. That means a lot coming from a guy with your pace. It's a little scary putting your process and knowledge out there when there are so many more knowledgeable guys than me and I would be so embarrassed. I keep waiting for that moment where someone shows me an important piece of the puzzle I missed or got something backwards. I'd feel really bad if I led guys down the wrong path. If I do, I guess they'll find me at the end of it waiting on them because I'm master of that path