Race car suspension Class

In summary,-The stock car suspension is important for understanding the complexity of a Formula Cars suspension.-When designing a (front) suspension, geometry layout is critical.-spindle choice and dimensions, kingpin and steering inclination, wheel offset, frame height, car track width, camber change curve, static roll center height and location and roll axis location are major factors.-The first critical thing to do is to establish the roll center height and lateral location. The roll center is established by fixed points and angles of the A-arms. These pivot points and angles also establish the camber gain and bump steer.-I have used Suspension Analyzer for years on Super late Model stock cars as
  • #631
Thanks, RM! The bumpsteer is not something I have messed with yet. Quite frankly, I'm not sure how to. With the rules - 'stock' - there's not a lot of wiggle room for me on this even though I hear that the A-bodies have good bumpsteer. To me, there's only so much that can be done with the steering - there are no aftermarket components that can correct the bumpsteer - at least with stock-appearing, tie rod ends and center link.

Or am I missing something?
 
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  • #632
You should at least learn how to measure what you have, even if you can not correct it. It builds toe in. If you are going to master a race car you better know all about caster camber, toe etc..

just saying..if nothing else you can rebuild it at the track to some know bench mark after a wreck.
 
  • #633
Ranger Mike - Last year we measured and re-measured caster, camber and toe. (I also bought wheel scales and a caster/camber gage.) Tire temperatures were checked religiously. Up to this point my approach had always been to put some power into the car and drive the wheels off of it. That worked - to a point - we broke the track record right off the bat and won two races. But, as you know, that is never enough so that's why we kept pursuing speed - to that end we regressed and by 2/10ths.

Over the winter we have not focused at all on the motor but instead turned to this forum and the CTA software.

I've borrowed some 10" stands to put the car on. We'll be plotting out the car this weekend. When we ran the software in continuous mode the RC moved voilently to the left, and down. I'm going to start with the springs you suggested and set up the lower control arms 'level'. From there the goal will be to get the RC as you stated.
 
  • #634
Excellent plan. I would check the rear end for rear steer as well. Takes a few hours to pull out the springs and measure wheel base thru bump but can see what is happening at the rear end while cornering. Once complete you have no worries on that end. Then back up front and try to get the RC offset correct and try to maintain it close to 3 inch thru cornering. At least the first 1 /2" if nothing else. Just remember it is a stock class and you are very limited by the rules. Not much to be done..but..little things matter and if you can have many little things working for you then you will have a better car than the rest.
 
  • #635
RM - Whew…measuring, changing and re-measuring RC - what a process! But we have been able to get the RC to start out at 3.4" above ground, 2.8" Right. But, I have measured my CL based upon the frame center, and not tire patch. Since I'm running offsets and spacers the tires would cause the CL to shift 1.5" right. Thoughts?

What I have also noticed, by driving change with the software, is that there is a certain rate of change caused by two variables - dive and roll. By "Analyze Suspension" the software is telling me that I should expect 2.3" dive and 1.6* roll. Is there a particular equation I should be looking at?

Also, the software discusses 2 CPS for RF (LF = 0.85RF) and 1.6 CPS for the rear. Steve Smith's Advanced Race Car Dynamics suggests 2 CPS and 1.4 CPS. If I go 'by the book' my RF spring rate will increase to 1163#! This seems way above anything that I've talked to others about.

Right now, based upon my current set up my RF CPS = 1.8, all others = 1.6

If I follow the logic of 1* roll / 1" travel, the RC:

@ 1 = 2.5"H, 5.3"R
@ 2 = 1.7"H, 10.7"R
@ 3 = 0.7"H, 23.0"R

But, if I plug in the MAX dive/roll that the software suggests (2.3" / 1.60*):
RC = 1.5"H, 10.4"R

Finally, my anti dive is: RF = 8%, LF = 5%. This is very close to 'textbook' - 10%, 5%.

It may not look like it (by looking at the car) but we have made several changes. Interestingly enough, we are running the same BJs for the lowers and the same for the uppers. (I would have expected to stagger these.)

I really like the software.
 
  • #636
Wow- good job racer! Gives the public an idea just what we do in the winter in a cold garage!
There is a lot to digest. When you use wheel spacers to move the vehicle center line to the right we are adding left side weight. I assume your roll center calculations are based on the final adjusted center line. We try to run as much left side weight as we can get away with. Even used to crank in the ARB (sway bar ) adjuster before rolling across the weight scales.

I am very impressed that you have taken the time to read up on your ideal setup from various source..Excellent.
To all racers a word of caution- I swear by using software programs like this one to measure out where the car is and base line it. BUT,,do not get over zealous and start gaming the race car set up. Two huge factors will ruin your ideal set up you have gamed out.
Reality and Aero. All the software in the world can not predict real world things like damper dynamics ( shock action), true spring action, ARB action, and the 32 some moments on a typical stock car. Shocks will heat up and permit more dive/roll during the race. You are burning off weight every lap ( as you eat gasoline). Tires go away from lap 1 on..just the reality of it.
Aero dynamic drag is a lot more problematic and can not be accounted for with this software.
I rely on the software as much as my pyrometer. It is a tool only and should be thought of that way.

On dive and roll, i think you have done a lot of work and should stop.
You have the RC exactly where it should be at static. All the software has indicated it will migrate to the right. I don't really care after 2 inch travel where it ends up as the the max weight transfer has already happened.

Until you can read the shock stops after a hot lap and know actual shock compression, everything else is a guess.

no way will a 1100# spring work.

Good job on anti dive. I think you have taken it as far as you can in the virtual world. Now back to checking rear steer and making sure we don't have suspension bind anywhere. Make sure you do thorough bolt check and get rid of any farm bolts and bolts under grade 8.
you got a real good jump on the competition this year.
rm
 
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  • #637
"I assume your roll center calculations are based on the final adjusted center line."

No. If I need to take this into consideration then my RC is 4.3" to the right. If I make any efforts to shift it further left, the RC really starts taking off to the left which will only make the car 'feel like' it has a very soft RF spring. (Which was the case last year.)
 
  • #638
Also, to get the RF CPS to 1.8 I ended up with a 950# spring.
LF 850, RR 150, LR 200, all equal 1.6

When we tore the front suspension apart we immediately noticed issues with the lower control arm mounts - they weren't lined up. This took a bit of 'fabricating'. Afterwhich, we used 9/16" drill rod to make sure the pivot point was in line. We then used a digital angle finder to make sure that both sides were as close as possible - 0.5*. We also used a tape measure to make sure the heights were the same.

With all this, and since we are allowed to run tubular uppers, we contacted a respectable company to have uppers made with the specific caster offsets as well as the correct lengths to get the RC where it needs to be.

Like I said, what a process! Hopefully we'll have a play-day this weekend.

Now all I have to figure out are my shocks. (Right after I check the rear end.)
 
  • #639
At this point I would not monkey with the Roll center location any more. It is migrating where it should. Concentrate on the tire contact patch and look at camber build your actual spindle set up. Use a bump steer gage so you know what it is doing in 2 to 3 inch dive..and on left front too. I would say you have gotten just about all you can out of the software..now it is real world time on new fabricated front end parts..Sounds like you found some major areas to improve!
 
  • #640
As a reference, last years RC was 1.9H, 8.5L! The car acted like it had a 2-ton gorilla jumping up and down on a 5-foot torque wrench! It would roll on the Right side severely.

We're now in the process of measuring bump steer - front and rear. So far, interesting number on the front.

We're looking forward to the NEW car!…

Thanks, Ranger Mike! Booyah!
 
  • #641
Bingo..no wonder the car was pushing going in and loose coming off the turn. If you have a front track width of 65 inch and the RC is located at 32.5 or centered then 50% of the weight would roll thru the center when cornering. With the RC located 8.5 inch to the left you had only 37% of the car weight rolling thru the center..not enough to stick the RF tire and not enough to transfer to the right rear on corner exit to hook up the rr tire. With a RC at 3 inch to the right of center you have 53% of the weight rotation thru the RC..much better and the recommended location..because you have enuff to plant the tire but not enough to start to lift the LF tire like the old sprint cars used to. I think you found the underlying problem. This is huge. If you had not taken the time to find this all your efforts would be to band aid the problem.
The other teams having the RC 8 inch to the left would be chasing their tail with cranking in rear steer to hook up the car, swapping out RF spring / shocks , preloading the ARB, cranking in cross weight, adding stagger, to find the best combination. This process will drive you CRAZY.
Good job! let me know bump steer and don’t forget to check akermann my other pet peeve.
 
  • #642
The lower control arms were set at the same angle as ride height. The centerline of the car was established and then each rotor was set parallel. A bar was clamped against each rotor which represented the contact points of the face of the tire (when setting the toe by string method). The contact points were 21” apart. A plumb bob was then used to establish the toe. A ruler was laid on the floor and square to the car’s centerline. Each tie rod was adjusted until the bar was parallel.

The bump was then measured. Again, it proves why the car liked ¼” of Toe Out.

The Pitman Arm and Idler Arm seemed to be pointed in equal and opposite directions.

The RF is really strange – it’s OK through the first 1.25” of bump but then really starts to toe in!

The LF has a gentle curve which suggests that something needs to be changed.
 

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  • #643
not too bad,,you are allowed .030 to .040" toe per 1 inch bump..don't mess with it..not worth the effort. btw that is a classic case of the outer tie rod end to high or too low..see chart attached
 

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  • #644
What would you suggest setting the static toe-out to be? My thought is:

0.08" (LF @ 2") + 0.05" (RF @ 2") + 0.13" = 0.26"
The 0.13" would be to compensate for the steering linkage shrinkage during cornering. This would likely net a dynamic Toe-out of 0.05"?

Do I set this equally? Or as per the respective sides toe change? Meaning, LF = 0.16" toe out, RF = 0.10" Toe out.
 
  • #645
Ok, Rear Bump. We set the gage on the LR and bumped the rear end up evenly 1". The front indicator moved -0.006" The rear indicator moved -0.008" - telling me that the wheelbase on the right side is getting shorter.

We did not check the RR.
 
  • #646
If you can adjust the bump steer and Ackermann ..read thisI looked over my past post and on page 1 post 13 we discussed Bump Steer. I never did go into Toe and Ackermann in detail so maybe we should at this late point.
Toe-Out. If you have to ask what it is please leave this post. Toe in is for production cars with spongy rubber steering bushings. The theory is at speed the tire will move from toe into toe out condition. Race carts have metal bushings with no give so they are toed out at static alignment. If no toe out was dialed in the car would be floaty. You need d a degree of toe out to keep the tires from wondering on the track at speed.
When you go into a left hand turn both tires are turning about a common center. The inside or left ft. tire is closer to that center point and has to turn sharper. It is running a shorter radius. Rt.Fnt. is using longer radius. Both tires are pointing in different directions while in a turn because of this. Static Toe out is used to balance out this difference and make best compromise so that each tire follows the ideal path on its own radius. When the front wheel is not following the ideal radius it is pointing against the radius and scrubbing off horsepower. If you go with too much toe out you will be scrubbing the tires on the straightaway. Using only a tape measure to measure toe is a no-no because tape flex can add a lot of error on a 65 inch track width car. As little as 1/16 inch difference can mean a lot of headache.

Ackermann steering came about in horse drawn carriages in 1818. Rudy Ackermann wondered why the wheelwrights had to replace the metal hoops on the wood wheels so often. The wagons and carriages of the day actually scrubbed off the rims in a turn because of the above described different steering radius. So he came up with Ackermann.
Ackermann is used to keep the tires from slipping sideways when following the non-ideal radius in a turn. It works by having both front wheels to have their spindles arranged as radii of a circle with a common center point. This center point, when the steering wheel is pointed is straight is usually the middle of the rear axle. In a turn the intersecting point of the axes of the front wheels will fall on a line that is the center line of the rear axle which means that the inside front wheel is turned at a greater
The bottom line is that modern steering linkage is not a simple parallelogram, but by making the length of the center link shorter than that of the distance between each spindle axis the steering arms of the hubs appeared to "toe out". As the steering moved, the wheels turned according to Ackermann, with the inner wheel turning further.
Ackermann steering is actually dynamic toe-out. It only creates toe out in a turn which is what we want... Minimum toe out going down the straight. We need a large amount of toe out on a short track race car IN THE TURN. Not on the straights. Ackermann is gained as the turn the steering wheel more in the turn. We need Ackermann on the right and left wheel as we may need to counter steer to avoid spinning out.
 

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  • #647
How to measure Ackermann.
If you are into racing and ca n afford it buy some turn plates for $750.00 see photo. Or buy some wax paper and a cheap plastic protractor. Use a straight edge and mark a zero line on the garage floor on the RF and lf tires when the car steering is centered. Crank the RF to the left 18 degrees and mark a line on the floor. Use the straight edge to mark the line where the lf tire is pointing. This is the Ackermann you have in the car.
How much Ackermann?
The left has to steer 15 % more than the right front. A typical asphalt track car needs 3 to 4 degrees more Ackermann on the left front in 18 degrees for right front steering. You crank the wheel to the left and hopefully you get 21 to 22 degrees.
One way to gain Ackermann is with BUMP STEER. For short track asphalt cars we want zero bump on the left front. No bump at all in compression or dive and rebound. Right front we need 0.035 to .040 “bump. Don’t forget the right front is the steering tire. The deeper you go into the turn the more bump you have. As the right front bumps to toe out the more you can steer to the left without pushing.
Whatever you do...do not change one the length of one steering arm on one spindle. It will really mess up the whole steering parallelogram.
 

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  • #648
This has been a long read but what a treat! Thanks to all involved for sharing so much knowledge, I came around interested in the physical aspect of stock car racing and I will now need months to digest all I have learned lol.

I'd like to ask some questions if you don't mind, as I'm curious to know some things in more detail. For example, I have seen some references to shock absorbers but no indications of the ~ damping ratio stock cars usually run (Or the max/min range). Also, are different SA mounted left and right, or is the need for assymetrical setup covered just by regulating them differently?

Cheers
 
  • #649
welcome Al
I am out of country this week..drinking plenty of fine German beer

I can tell you every shock ( damper) application is track specific. Mount location and angel are pretty consistent but important thing is to mount them bind free with best geometry to make max use of the dampening regardless of direction. The ration compression vs rebound varies in application and track, banking, speed..example..it used to be common at Daytona to run shocks with 12 inch travel..
 
  • #650
Enjoy the german beer, I have swallowed enough of it to know it's one of the best ;-)

Thxs for the comment, I take it then that the teams generally just shop shock absorbers for their applications and trust the seller's choice, right?
 
  • #651
Al, the typical door slammer stock car racers will carry a couple of different shocks depending upon the stupidity of the local track rules. If they are permitted tuneable gas shocks then life is a little easier. Most tracks dictate you can only run ' stock" tube shocks so about all the racer can do is mount it upside down form minimal unsprung weight. We always carried a ' tie down" shock for the fronts to tune it in if we had a hook up problem. All the super later model fast track guys run 3 way gas shocks like the Penske. Shocks are the final tune thing once you find proper spring weights and ARB configuration.
 
  • #652
Al,

I'm definitely not a shock guru but I can tell you that after evaluating our RC - motion ratio is huge. Just because you bought a high-dollar-latest-and-greatest shock does not mean that the car will think it has one. As Ranger Mike pointed out it has to do with the rules. Our rules say a stock mounted, rebuildable shock in the stock location. If we were allowed to mount the shocks closer to the balljoints that's when the car would have truly 'felt' like I had spent the money on the shocks. We were running the same shocks that everyone else was buying - because the local hot shoes said it was the best. But, once you start understanding things you realize that what works for one guy will not work for you. Unfortunately, you have to make the investment in spare parts and, like Ranger Mike said, "Tune".

I've always understood shocks by their numbers, 6/6, 3/5, 10/4, etc but the shocks are actually controlling the rate at which the weight is being transferred. A '4' compression will let the weight transfer almost instanteously. A '7' compression slows it down a bit. But as Ranger Mike points out a lot of this has to do with the track configuration.

A high rebound number will 'hold' the weight at the corner while the spring pushes against it.

We have opted to go in a different direction than we did last year. Our RC will be much more favorable and our shock rates, fingers crossed, will improve on how fast the weight is transferred - we're trying to slow it down on the compression side and speed it up on the rebound side.

But for right now all of our attention is on the motor - we went to change the oil pump and saw that the #3 main was trashed, #4 & 5 rods are the worst I've ever seen and the #5 cylinder wall is scored up - a major lack of lubrication all the way around. We have another block/crank at the machine shop and new pistons on the way. And the season is fast approaching!
 
  • #653
Thxs for the answers!
 
  • #654
rad had major good points...am still in land of beer and machine tools..rad..are you permitted to run oil line from oil pump to the front oil gallery of the block ??
can you open up oil galleries in your engine block for more volume? I think you need high pressure oil supply coming in from front of engine as well as standard oil gallery delivery. The oil tends to wash by the 90 degree turns and starve off the rod bearings on front of engine. even a 1/8th inch line will benefit you a heap big much.
 
  • #655
I never thought about tapping into the back and feeding the front. But, as I read the rules this should be OK. Right now I'm running a high volume pump with a 9qt pan and restricted push rods. There's also a drain back on the right side head to the oil pan. The next step is to shim the pump to get greater pressure. I'm also thinking about dropping the oil viscosity back to a 0W30. (I run XP1 now.) to help with draining.

I've also thought about restricting the lifter galleries.

And, surprisingly the 1,2 &3 rod bearings looked good. Once I pull the crank out I won't be surprised to see something blocking the #3 main feeding the 4/5 rods. That's my hunch.

Look forward to your discussion on shocks. This is something I'd like to learn more about.

Enjoy the beer! I've had a few myself...and the local food as well...
 
  • #656
Rad, make sure the camshaft bearings are aligned with the oil gallery. With block upside down you should be able to stick a dowel rod thru t he main bearing oil hole straight to the camshaft bore. You may clogged gallery or misalignment here.

The venerable SB Chevy is pretty good at oiling things..but..if you look at the schematic you can see the oil goes through ten 90 Degree bends before passing through the camshaft bearing and hitting the mains. Each 90 degree turn cuts pressure by 2 PSI so you lose 20 psi at the most critical bearing..then you lose another few psi for the rod bearings. We all know the longer the hose the less the oil pressure, especially with all the passages and turns before you hit number 1 rod bearing. So we increase the oil gallery diameter and radius the corners as much as possible and avoid using 90 degree hose fittings to keep maximum psi in the oil system. We drill and tap the oil passages to the rocker arms to cut down on too much psi on top of the engine.

Another thing is the old blocks never used filtered oil on the big number 5 main thrust bearing. It was oil straight from the oil pump. You will note the oil relief valve by the filter will pop open and permit oil to by pass the oil filter once PSi gets bigger than the oil filter can handle. One estimate is 50% of the oil run thru a high rpm engine IS NOT FILTERED. Always use a fine mess screen on the oil pickup.
I like an additional oil feed coming in from the front to keep the oil from running past the 90 degree turns. Oil from t he front of the engine tapped in line will tend to meet the oil coming up through the block and force it to turn the 90 degrees. One more thing..all the oil will have been aerated by the oil running past the valve lifters and air bubbles in the oil is not a good thing. The external oil line drawing from the oil pump, UNFILTERED is just cheap insurance in my opinion.
 

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  • #657
Ranger Mike, anybody who knows me knows that I'm not the 'follow-the-leader' type. That's why I'm on here picking your voluminous brain. That's why I bought CTA from Performance Trends. And that's why I run the Small Block Olds 350. I decided that I didn't want to be cookie-cutter. Everyone else runs the 602 GM Crate.

I measured the oil that was drained - 5 qts! That is extremely embarassing but it is what it is. I KNOW I put 10.5 qts in but it's obvious that we had a very large leak. (My pan holds 9 qts.)

I also checked the oil passages - all clear. Knowing now that it only had 5 qts explains everything. We'll be switching to the Mobil 1 0W30 Racing oil this year.

And, the Olds cam bearings are a very different animal.

But, just last year, straight off the trailer fresh from a winter diet the car broke the track record. This was a car that was literally 'stock' - no RC evaluation at all. Stock anti-dive.
 
  • #658
Rad..no doubt about it..you are a true racer..having aid that..should i dig out my notes? i remember a fellow who raced a 350 Olds engine and may have something on the oiling...?? What year is the block?
 
  • #659
Dig out the notes, RM! It's a 68-76 block. My crank is ground for larger than stock bearing clearances. I have made a change this year to reduce the rod side clearance.
 
  • #660
ill see if I can get in the car hauler..locks may be froze...:eek:
 
  • #661
Rad, had a buddy drag racing the olds 350 w30 option I think it was..
only note I have is Forged pistons, 403 rods w/ARP rod bolts. Slightly stronger than 350 rods.
Forged 330 crank, if you have one lying around; otherwise, the nodular iron crank from a 350 would do just as well. Main studs and add main cap steel straps.
Windage tray and 6-quart oil pan from Toronado.
Make sure the oil that winds up in the valve train and on top of the heads can drain back to the pan..Restrict oil flow to the top end too.
found this link too


http://www.442.com/oldsfaq/oldsfaq.htm#Table of Contents

the pic is for an Olds engine..because the cam timing chain and fuel pump are splash oiled I think it is for the 350 cid.. ..not sure it is small block..can you tell by oil pump? That is one snakey oil system..could be improved on.
 

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  • #662
If I may ask another race car suspension question, what is the typichal camber gain in an indycar/champcar racer for road and oval courses? Given how little they seem to roll, is that even noticeable and important? The huge amount of static camber coupled with the little roll and small suspension travel (Around one inch IIRC) leads me to think the parameter is not really important and probably sacrificed to aero, but still would like to know -if anyone can share some knowledge.
 
  • #663
welcome Al..in my opinion it is all about the tire contact patch and camber build is the enemy..looking at it from a designers point of view if you have unlimited funds and can do it go with the longest control arms and make them parallel
 

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  • #664
Ah yes that's Smith's book, got it :-)

Explains things quite well, but there's a lack of detailed data like what I asked. Looking at champcar suspensions you can see both that they have unequal length and non parallel arms, so there must be some desire to gain camber. But how much? Probably little as the cars have almost no roll, maybe what they want is to control the roll centers better, no idea. Wouldn't parallel arms make the roll centers move a lot more?
 
  • #665
Al I would say its all in the book summed up, it is compromise between minimal camber gain and minimal Roll Center migration.Camber — Camber is the angle of the wheels in relation to the ground if you look from the front of the car. Teams adjust camber to improve a car’s handling characteristics. The tire’s relationship with the road changes as the suspension moves through its travel. Ideally, car designers want a camber curve that keeps the tire straight up and down when the car is driven straight, and leans the tire in slightly (1 to 2 degrees of negative camber) during cornering. Camber allows the weight of the car lean on the outer, more loaded tires, providing additional contact in a corner. However, on level ground and straights, the more camber it has the less contact patch area between a tire and the track surface. hence less speed.

There's a reason why F1 teams run 3-4 degrees camber and NASCAR runs as much as double that. Both on "radial" tires.

As far as I know NASCAR runs about -4 static camber on the RF and +7 or so on the LF. RR -2, LR +2, give or take.
BUT This topic is mixing a few things all together and I thought I would try and clarify.

Firstly, camber gain and static camber are not the same thing.
Static camber is the angular misalignment of the tires center line from a vertical plane when stationary measured in degrees.
Camber gain is the change in camber with changing geometry or put simply thru bump or droop and is measured in degrees per inch movement.

I think we are talking mostly about static camber and formula cars do not have much built in camber gain.

Camber gain is the change in camber with ANY change in geometry. For most front suspensions two things effect camber gain.
Steering linkage itself by cater change and the resultant scrub effect ( think go-cart steering).
Suspension linkage and related geometry. ( think dynamic).
From what I have seen formula cars do not seem to have much camber gain from either.

Camber gain is generally obtained by unequal A-arm suspension, but even equal length arms differently angled can provide camber gain.

Unequal and non parallel links are the compromise.
Formula cars tend to have fairly parallel control arms on the front suspension. Very much inclined, but fairly parallel to each other.

Suspension travel on a formula car is relatively quite small with how stiff the car is for aero so to some degree camber change with jounce is going to be small even with some non-parallelism.

Before Nascar started to regulate the dimensions of the suspension components, some teams ran a lower A-arm which was very short which gave them a HUGE camber gain from suspension displacement. They had to run a large static camber to compensate. What happens is the tire ends up with some, much smaller, positive camber at race speed when the nose is pushed down by aero.

The tire and resultant heat generated by cornering is the limiting factor in choosing appropriate camber settings. Too much on a stiff tire and you overheat the inside edge, too little on a soft one and you cook the outside. The whole radial/bias ply comparison is pretty useless these days because the regulating organization tells you what tires you can race. So you end up adding camber until you blister the inside edge of your tire and then back it off a degree.

Negative static camber helps keep the tire RELATIVELY vertical during body roll.
Formula cars run very little or even no net negative camber, specially for the inner wheel.
The intent of static negative camber is to land your dynamic camber wherever you want it, which is a non-zero value - several degrees or much more to get the additional cornering force, depending on how much you can get away with your tire.

Dynamic camber build means the inside wheel will get extra negative camber - outside wheel loses some. Since formula cars run such stiff springs your body roll angle and maximum camber gain through cornering is quite small. One downside of camber gain is effect on braking. With dive under braking, camber gain kicks in and compromises the tire contact patch. From my experience breaking performance isn't really affected until you start going over three degrees of negative camber, more or less. Even then you'd have to run like four degrees to notice a subjective difference.

I once tried to gain advantage by dialing in the camber for qualifying to get an edge on cold tires. Found that cold tires liked more camber gain which tended to be favored since handling was so bad on cold tires. However, this compromised hot tire handling and had to reset the camber after qualifying and became a real hassle. One old time winner of 500 feature races once summed it up ”qualifying don’t pay nothing”
 

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