The Art of Gitting Gud - Or How to Reduce Understeer

I am presented a problem in which under certain circumstances the car does not go where I turn the steering wheel. I am trying to solve the issue of "doesn't go where I point it".

Using TrackAddict, I overlayed two laps together (ignore the laptimes, they are inaccurate due to GPS timing) and synced them to the entrance time of the intersection. I can see on the white dot that I did not scrub speed fast enough, thus causing me to understeer and go wide. On the blue dot, I scrubbed speed hard and fast, and was able to make it through the roundabout much faster because of that. 

However, both times, I understeered much more than I wanted to, and overdrove the front right tire as a result, causing a bit of shredding. I want to avoid understeer under throttle, thus saving my front outside tire on turns like this. I suppose I could scrub even more speed and enter it even more slowly, but I can't help but feel like I'm leaving seconds on the table. Is the solution really as easy as "enter slowly"? At what point does "enter slowly" become too slow? 

Car setup: 

2020 Subaru WRX

-2.0 degrees front camber

0 degrees front toe

-1.85 degrees RL camber, -2.20 degrees RR camber (non-adjustable)

0.20 degrees rear toe

225/45R17 Falken Azenis RT660 mounted on 17x8 +55, 43 PSI front (to avoid sidewall rolling), 43 PSI rear (to promote rear rotation). 

OEM, non-adjustable 24mm F 20mm R sway bars. 

We need: 

tire sizes. 
sway bars? Adjustable?

Wheel sizes.

How soon are you getting back on throttle in both laps?

also, we can't see the cones, so we can't tell if you are coming in to shallow or too deep. 
 

are you hitting the apex? what is the corner before and after looking like?

"sometimes the most time is found in getting the slowest corners correct. Otoh, there is a lot of time to be had in the big corners." (Thanks Ross Bentley!)

In reply to Hey guys! It’s me! :

Oops, 

225/45R17 mounted on 17x8 +55, stock non adjustable sway bars (24mm F, 20mm R). 

I'm a bit peeved that out of the 8 laps, only one video was captured, and it was my 2nd practice lap where I threw it into 4th instead of 2nd. Hopefully this gives you a decent idea of what the course looks like. The entry is about the same on every run, with minor changes in entry speed. 
In the video you can kinda see that I'm nursing the throttle such that I don't lose speed in the turn but I don't power on until I start to straighten out.
I guess what I'm really asking is how can I engage throttle earlier in the corner without upsetting the car? 

Maybe it's the location of the camera but my opinion is that it appears to be pushing from the moment you turn in. You're coming in too fast. 
 

I'd try braking sooner and/or harder, get more weight transfer to the front to help with turn in. Then when the car takes a set you can work on powering it out as you unwind the wheel. 
 

In reply to Floating Doc (Forum Supporter) :

Sure, that's perfectly reasonable. How slow is too slow, though? Is there a certain point where it would be faster to just scrub tire and push than it would be to brake hard? 
I also need to get better at learning courses, I don't think I learned that until maybe my 2nd to last timed lap. 

Looks like you're waaaaay late on everything, which certainly isn't helping. Can't see your inputs but from how late you're turning in I'm guessing you're turning pretty abruptly which also isn't helping. Finally, it's a Subaru, it's going to understeer on turn in to some extent.

Also, tell the course setup people that the course lines go on the outside of the cones, not the inside.

Yes, you're correct in that I was turning in way too late. That was the only video I got, because my lap timer was acting funky. Must've been the heat.
Anyways that was corrected later in the day, in the video I was experimenting with what kind of speeds I can carry and I was certainly going too fast for the course in the video. I had a more... exponential approach to turning for the first 2-3 laps. Turn in a little, and then turn in A LOT. So it looks very abrupt because it probably was. 

I'd like to think I had smooth steering inputs otherwise, I think the most abrupt turn in I had was on the 3rd gate after the intersection exit, it was much more leftwards than I had initially thought. 

Best piece of advice a driving instructor gave me was, “Most people drive too fast in slow corners, and too slow in fast corners”.

I had the fast corners down, but once I got to where I didn’t over-drive the slow corners, the times went down.

racerfink said:

Best piece of advice a driving instructor gave me was, “Most people drive too fast in slow corners, and too slow in fast corners”.

I had the fast corners down, but once I got to where I didn’t over-drive the slow corners, the times went down.

That is some really good advice. 

So the solution really is just "enter slowly". But my sub-question is still posed, how slow is too slow? How do I strike that balance? 

Maybe I'm thinking too hard about it, and I just need more seat time. 

For car setup here's a few things to try.

• Add a touch of front toe in.  At 0 static it's almost certainly toeing out under power.  To really dial in the toe you need to know what the Ackerman is doing in the problem corners but you can get there just by experimenting.  If toe in doesn't help try some toe out
• Move the rear toe closer to 0 to promote rotation
• Your tire pressure seem really, really high.  You're over 10 psi higher than what I've seen with those tires.  See if you can borrow a pyrometer so you can see how the tread is working.
• Try running a lower front tire pressure compared to the rear
• I'm assuming that you're also running this car on the street otherwise I'd suggest more front camber.

Don't do all of those things at once.  I'd start with the tire pressures.

As far as driving is concerned, Subarus generally don't like to turn under power so you need to adjust what you're doing to reduce that.  Get the car slowed down and turned more by mid corner so that you can open up the wheel more before you start adding power.  That's going to require trail braking.  Basically, if you miss the apex or can't get the wheel straight enough to add power you were carrying too much speed mid corner.  When it does push a little less wheel and less power is likely faster than just cranking in more steering and keeping the power on.

In reply to APEowner :

Thank you for all these items to address. I will continue to play with tire pressure, I didn't really have a chance to because they were running a very tight ship and I didn't have time to jump out of my car and start airing out/pumping up tires between laps without missing a run. I will attempt to address them as how I understand them here: 

- Skosh of front toe in

I avoided running any toe in the front because it's a daily vehicle and I have a set of high treadwear all seasons that I use for daily duty. Since toe is a wear angle, I wanted to avoid wearing my daily tires prematurely (even with keeping it at a tire rotation every oil change). What would you recommend to start with? I got 0 L/R toe from a post I found on NASIOC (yes, laugh all you want), but I'm willing to go more (within reason) if necessary. 

- Rear toe closer to 0

Was the rear toe I have posted above not close enough to 0? I was under the impression that it was "close enough". I think it was something like 0.05 L, 0.10 R. 

- Tire pressure too high

I did 43 PSI front to help with sidewall rolling. With -2.0 front camber and 35 PSI front, I was still rolling sidewall (albeit much less than when I was +/- 0 degrees front camber). Would an IR gun be ok for it? My girlfriend bought one on Prime Day last year because of obvious reasons, but it's being unused. All pressures were estimated because I had a dumpy tire gauge from O'reilly that I bought because I was already there for oil and it had a bleed valve. The compressor I have also outputted the pressure, but again it's a cheapy tire compressor. 

- Lower front pressure than rear 

Yes, I plan to do that. I regret running 43 square, in hindsight I should've tried 38 front 43 rear. The local go kart track runs time attack nights for cars every couple weeks on Friday nights and they have one that just happens to fall on a weekend the lady friend will be out of town. I've been wanting to go back to see how lap times change since last time I ran it I was on a different set of tires with +/- 0 degrees front camber. Having a static track that doesn't change layout will help diagnose car set up. I'll have more time in between to experiment with tire pressures. I think I will try 35 front, 40 rear, sidewall be damned. 

- More front camber

You are correct in that it is street driven, I didn't add more front camber for the same reason I didn't toe in the front. This model of WRX allows up to -1.5 degrees of front camber, but I added camber bolts to the bottom hole to push the hub out a little more to get more negative camber. I think with this setup, I can go up to -2.6 degrees of front camber, which seems like too much for the street but I don't know anything about that. First time car set up.

I have more experience with a '94 300ZX and an '02 RSX Type S, this is my first AWD vehicle so I still have a lot to learn. In the Z32, early throttle meant the tail end slips out, and low but consistent throttle was the name of the game. In the RSX Type S, early throttle actually really benefited turn in, from what I experienced. It might have helped because it had an uprated Progress rear sway bar. I guess I have to drive the WRX more like the Z32 and less like the Type S.

Lower front pressure a lot and raise rear pressure.

You have high treadwear all seasons and you're afraid of wearing them out? That sounds wrong, they're high treadwear, they'll last forever even if the wear is a bit uneven. 2.6* camber and a bit of toe (out...not in unless you want it to turn in even slower) is totally reasonable for a street alignment unless you're going to be putting like 50k miles a year on the thing. Another thing worth noting, it's awd, and iirc in normal driving it's basically fwd, so that zero toe is probably becoming at least slight toe in with any amount of throttle anyway. I know it's not a direct comparison but changing from the stock toe in to very slight toe out on my fiesta st was the single most noticeable change I've made to it. So much more responsiveness and it has yet to cause any tire wear issues even on 300TW summer tires that I beat the crap out of.

APEowner said:

For car setup here's a few things to try.

• Add a touch of front toe in.  At 0 static it's almost certainly toeing out under power.  To really dial in the toe you need to know what the Ackerman is doing in the problem corners but you can get there just by experimenting.  If toe in doesn't help try some toe out
• Your tire pressure seem really, really high.  You're over 10 psi higher than what I've seen with those tires.  See if you can borrow a pyrometer so you can see how the tread is working.

Don't do all of those things at once.  I'd start with the tire pressures.

Agreed on these points plus . . . 

Get pyrometer readings if you can and make adjustments per the readings. 

Given APE's and others comments your initial set up seems to be way off.

hunter47 said:

In reply to APEowner :

Thank you for all these items to address. I will continue to play with tire pressure, I didn't really have a chance to because they were running a very tight ship and I didn't have time to jump out of my car and start airing out/pumping up tires between laps without missing a run. I will attempt to address them as how I understand them here: 

- Skosh of front toe in

I avoided running any toe in the front because it's a daily vehicle and I have a set of high treadwear all seasons that I use for daily duty. Since toe is a wear angle, I wanted to avoid wearing my daily tires prematurely (even with keeping it at a tire rotation every oil change). What would you recommend to start with? I got 0 L/R toe from a post I found on NASIOC (yes, laugh all you want), but I'm willing to go more (within reason) if necessary. 

- Rear toe closer to 0

Was the rear toe I have posted above not close enough to 0? I was under the impression that it was "close enough". I think it was something like 0.05 L, 0.10 R. 

- Tire pressure too high

I did 43 PSI front to help with sidewall rolling. With -2.0 front camber and 35 PSI front, I was still rolling sidewall (albeit much less than when I was +/- 0 degrees front camber). Would an IR gun be ok for it? My girlfriend bought one on Prime Day last year because of obvious reasons, but it's being unused. All pressures were estimated because I had a dumpy tire gauge from O'reilly that I bought because I was already there for oil and it had a bleed valve. The compressor I have also outputted the pressure, but again it's a cheapy tire compressor. 

- Lower front pressure than rear 

Yes, I plan to do that. I regret running 43 square, in hindsight I should've tried 38 front 43 rear. The local go kart track runs time attack nights for cars every couple weeks on Friday nights and they have one that just happens to fall on a weekend the lady friend will be out of town. I've been wanting to go back to see how lap times change since last time I ran it I was on a different set of tires with +/- 0 degrees front camber. Having a static track that doesn't change layout will help diagnose car set up. I'll have more time in between to experiment with tire pressures. I think I will try 35 front, 40 rear, sidewall be damned. 

- More front camber

You are correct in that it is street driven, I didn't add more front camber for the same reason I didn't toe in the front. This model of WRX allows up to -1.5 degrees of front camber, but I added camber bolts to the bottom hole to push the hub out a little more to get more negative camber. I think with this setup, I can go up to -2.6 degrees of front camber, which seems like too much for the street but I don't know anything about that. First time car set up.

I have more experience with a '94 300ZX and an '02 RSX Type S, this is my first AWD vehicle so I still have a lot to learn. In the Z32, early throttle meant the tail end slips out, and low but consistent throttle was the name of the game. In the RSX Type S, early throttle actually really benefited turn in, from what I experienced. It might have helped because it had an uprated Progress rear sway bar. I guess I have to drive the WRX more like the Z32 and less like the Type S.

So, I apparently need to make sure I've had at least one full cup of coffee before posting.  I should have suggested some front toe out.  What happens is that under power the wheels are pulled in so your static 0 becomes something in.  You'll start to see tire wear somewhere around 0.5 degrees in or out depending on the car.  I'd shoot for 0.25 toe out.

Being all wheel drive the same thing happens in the rear but to a lesser extent because of the front wheel bias of the system.  Since you want the car to turn in easier a slight toe out would be helpful but they can get twitchy on the highway if you have too much.  I'd shoot for somewhere between 0 and 0.05 total toe in.  Actually, I'd probably even try a touch of toe out but I set my own toe and don't have to pay for it so the experiments are free.

You're probably maxed out on camber for a street car.

I'd work on tire pressures and driving before I got carried away with making alignment changes.

An IR gun is better than nothing but a tire probe is really the right tool for the job.  I admit to never having used in IR gun so I don't really know how useful or useless the information is.  Try it and see how consistent it is.  Do you get drastically  different numbers if you measure in different order?  If so it's likely that none of the data is good.

I've never autocrossed so I don't know how helpful this is but below are some techniques and tips I use for learning race tracks.

• Talk yourself around the track.  The dialogue goes something like "Turn one fast lefthander, third gear turn, in at the second pothole. Turn two sweeping left hander no need to slow as much as last time...."
• When analyzing lines think about the corner backwards.  Where do you want to be on track out?  Where do you have to apex for that to happen?  What does the turn in point have to be to hit the apex in the right spot?
• Work on braking last.  Figure out the rest of the corner, turn in, apex, apex speed and corner exit before trying to find out where your braking point is.  It's going to change based on the other factors.

How is your trail braking technique? Excellent, marginal, non existent etc. I can't see what you are doing with you feet but based on the in car video it appears that trail braking would help. 

Trailing the brakes aaaaaaall the way into the center of that corner would get the car rotating rapidly and once you really got it rotating you could balance it on the throttle.

The other technique that would work is left foot braking rally technique of pulsing the brake pedal to get rapid weight transfer but I would save that for very last.

You are correct about are loosing a ton of time. 

Lots of good comments being made on car set up. I'll limit myself to comments on the actual driving.

One thing I would change is to mount the camera inside the car where you can see what your hands are doing, even better if you can get your feet into the image.

As far as determining how fast to set your corner entry, it's better to brake earlier and go slower on your first run and work on your line. You can shorten the brake zone and increase entry speed with subsequent runs. 
 

understeering, and plowing around the turn is never faster. You'll run wide, and additional distance is almost impossible to make up. 
 

If I'm understeering, I'll lift the throttle for a fraction of a second and straighten the wheel, in order to get the front end planted and the front tires gripping again.  You'll lose less by getting off the throttle for that split-second and staying on the line.

But my sub-question is still posed, how slow is too slow? How do I strike that balance? 

If the tires are spinnin', you ain't winnin'. If the tires are making a lot of noise, you're too fast. Watch a really slow car that can do a really fast run, you'll notice they are smooth and the tires hardly make noises. Maybe little chirps, but that's because they are creeping up on the adhesion limits, not exceeding them. 

The biggest thing I learned to combat understeer was to wait an extra moment before accelerating.

dps214 said:

Looks like you're waaaaay late on everything, which certainly isn't helping. Can't see your inputs but from how late you're turning in I'm guessing you're turning pretty abruptly which also isn't helping. Finally, it's a Subaru, it's going to understeer on turn in to some extent.

I concur

One of my customers ran a 2018 WRX last year. We set his alignment at zero toe front and rear, 3.7 degrees of camber front, and 2.5 rear. He had Tein Coil overs (we lowered the car an inch I think), RS4 tires 225w i think, a CAI and COBB tune. The car was competitive in Autocross and Time Attack street classes. He was always near the front and said the coil overs, alignment, and tires were a huge upgrade in performance.

I've learned so much from the internet today. 

• Try out 35 front 40 rear (hot). Or should I try 30 front, 35 rear (hot)? Higher pressure in the rear to promote rearwards rotation, but my current pressures are way too high for a low treadwear summer/performance tire.
• Analyze tire temps. I might do some cardboard aided design for a guide to get the IR gun the same distance from the tire when measuring every time. Surely the temperature will not be as accurate as a probe, but it should give me a good idea of the temperature of the tire relative to the inner, center, and outer sections, which should give me enough information to make a more informed tire pressure change.
• Work on analyzing lines (corner entry/mid/exit speeds and angles) more on the sight lap. A problem that is unique to autocross is you don't get to nitpick the track the week before in Assetto Corsa. You have to learn it there, and in a short time. Sometimes you get 12 laps the day before, sometimes you get 1 lap the day of. Depends on who's organizing. 
• Enter the corner slower, either by means of scrubbing speed faster or slowing down overall lap pace. Drive the slow corner slow and it will set me up to drive the fast corner fast. I noticed after watching the video a few times that my line set up for after the intersection is all wacked out because I was too focused on correcting the understeer (it was also the lap where I went 1>4 instead of 1>2 - watch the RPMs and listen during the slalom, oops! Probably too focused on getting it back in gear and not on the right line to take). 
• Verbalize my track findings. I currently just keep them in my mind, but I can see how verbalizing them helps me recall it better. 
• Work on trail braking for when I do get the lines figured out. Trail braking assists rotation. This will probably be for when I make it back to the go kart track's time attack night. I've analyzed the lines heavily on Assetto Corsa and was able to make good lap times my first time out with a less aggressive alignment. Now that I have more camber and better tire compound I'll should be able to lower my times from last time as well as have good analytical data. 

Anything else I'm missing? 

In reply to hunter47 :

RE: Verbalize my track findings. I currently just keep them in my mind, but I can see how verbalizing them helps me recall it better. 

After walking the track I used to visualize the run as I sat in the car. After each run I tried to visualize putting together the best of each run into one very good run.

In reply to hunter47 :

Anything else I'm missing?
 

Yeah! Don't forget to have fun!

I would also recommend watching as many YouTube autocross videos as you can. There's a lot to be learned from people like Kinch Riendl, watching his videos and listening to his podcast. 
 

Instruction is very important for making progress. Ride with the fast guys, have them drive your car, take a school. 
 

I've done two schools, and hope to take another one soon. 

Floating Doc (Forum Supporter) said:

One thing I would change is to mount the camera inside the car where you can see what your hands are doing, even better if you can get your feet into the image.

Look man, everyone's got their thing, but I'm not gonna post my feet online for strangers to see, I know better than that. 

Also having fun is being able to thrash the car without worrying about police. I always have fun at autocross, even if I'm not fast or competitive.

Thanks for all the good advice everyone, I'll be back in a month with new stuff for you to nitpick!