This guide was written by Simon Edwards and gives us an in-depth explanation about how to qualify properly on iRacing. This guide explains some fundamental concepts such as warm tire behavior and driving tips.
The original source, can be found here.
Hi Guys,
Thought i’d spread some of my super secret info on Qual : )
How to Qualify the best you can:
- Step 1: go faster than everybody else on one of the two laps you are given
- Step 2: Race from pole.
Ok, it doesn’t just happen in this car, you have to understand a few things.
Fundamentals
Warm tyre behavior
- 1. Both the front and rear of the car can get to huge slip angles without suddenly running away.
- 2. There is virtually no load sensitivity, if the tyre is touching the ground it has grip.
- 3. The hotter you can get the core of the tyre the more of 1 & 2 is true.
- 4. The hotter you get the surface of the tyres the slower your acceleration and top speed is (low percent ie 1-4% ish).
Why does the above matter when thinking about Qualifying? well the simple answer is the cold tyre behavior is a different beast altogether:
- 1. Both the front and rear of the car has very narrow usable slip angles and the tyre will runaway very quickly if exceeded.
- 2. The surface temp to core temp ratio exaggerates point 1 (ie hot surface on a cold tyre is a death sentence).
- 3. There is a very pronounce load sensitivity to the tyre.
4. The cooler you can keep the surface of the rear tyre the more traction you get and a little more top speed.
What the above means when you are trying to push the car is that as you load the front tyres under braking two things happen; The front tyre ‘bites’ as the load is moved forward and the rears lose load which basically mean all the ‘grip’ goes to the front of the car in an exaggerated way, what makes this worse is that the ‘bite’ isn’t straight away there is a small delay which exaggerates this further.
The secondary issue is the surface heat of the tyres, if you lock up a front tyre even slightly then you won’t have grip on that tyre if you need it in the next one or two corners, this is just a very exaggerated from of what happens if you have a BIG slide on warm ‘core’ tyres (same is true if you slide or spin up the rears)
So what to do in Q?
- 1. Simple answer is warm your tyres
- 2. Drive diferently than you do on warm tyres
1. Warming tyres
The aim of warming the tyres is soley to get the core of the tyre hot and not the surface and secondary is to get the right balance between the front tyres and rear, if you heat the rears too much you will simply understear everyway, likewise if you do much at the front you will make the car too nervous.
2. Driving Differently
You have one simple aim here, you have not got the rears upto full working temp so the car is still very sensitive to the weight moving around, the way i counter this is to come off the power more gently and trail the brake much more into the corner than i would normally, this creates a slight corner entry understeer which means you can keep the car much more inline, corners where only a lift is required, lift early and slowly and apply super smooth steering and gentle power application.
Example laps:
1. Warmup demo lap
as i exit the pits you will see i start the old F1 style swerving, you should notice that i tap the brake everytime i change direction, this is to ensure i push the weight onto the front tyres which makes the rear slide, this is my rear tyre warmup phase, swing the car just enough that the car feels like it may run away from you and no more and slowly you will feel the swinging become more linear and harder to initiate, you have now got enough rear temp to start being aggressive.
by the time i get to the end of the straight i change what i’m doing i no longer tap the brake and i steer more aggressively, i am now generating some initial understeer followed by some of the previous oversteer, we are now warming both front and rear.
I will also use some of the corners to do extended sliding in one direction too, be careful with this that you don’t overheat a single tyre and make the car unbalanced because of it.
Once i’m half way round the lap alternating between the three above warmup tactics i will then go into ‘testing’ mode and i will deliberately try an aggressive swerve, if the car understeers and the rear sticks i will do some extreme steering to scrub the front tyres a lot (i do this once to the right, once to the left) and back to normal warming, after a few secs, another test swerve (in the opposite direction if pos) and repeat the specific front or rear warming that is required to get a balanced car.
Lastly i go into a ‘cooldown’ phase, i will make sure i have about 10 secs of no warming and no stress on the tyres at all to let the surface temp sink into the core and come down, you will see i go super slow and smooth into the last chicane, this makes sure that the rears are in the best state for the first corner and will give you the best traction out of the last corner and the first. I often cannot go faster through the 1st sector of my 2nd q laps because of this.
2. The Q lap itself
This is as i described in ‘Driving differently’ you will notice i never lock up, or scrub the front tyres on entry or get any real slip angle in the car at all, you may notice i occasionally do a quick counter steer on entry without any apparent oversteer, this is me just feeling the front load up a bit too much and i kill any oversteer that may have resulted before it even starts (this is the ‘jedi mind trick’ that one of the real world indycar drivers was saying they were having issues with in anticipating oversteer)
You may notice i run wide on entry into bruxelles, this was simply the result in me understeering between Les Combes and Malmedy and getting that left front surface too hot, i tried to compensate on entry but did not get it quite right, you will see i am super patient in getting it back and making sure i do not scrub the front tyre even worse to make the next corner a problem.
Lastly, never push the last corner! although your core tyre temp is now pretty good, being on a hot Q lap or two will get thoughs surface temps up and can bite bad just when you think you can lean on them the most, be super smooth and precise, losing half a tenth is better than losing 5 tenths!
I hope the FREE advice will help some of you with Q laps, you can also use the general ‘Drive Diferently’ advice for the first laps of the race too (donations welcome if it really helped)
If you want to do some donations, the original source can be found here.
Onboard Video:
Offboard Video:
