Vajingo
HalfDork
3/23/21 11:31 a.m.
Using pax, I generally only move up a position, maybe two versus my raw times. Pax is supposed to help you be on the level with the top driver of the day right? I can best my class, but I am nowhere near the top when pax is factored.
Does pax show how far off I am from top level drivers from the year before?
for reference this is last year, I am pax pos. 26:
PAX is a published thought experiment. The huge "what if?" of autocross. If we could equalize my crappy hatchback and his CP car, who would win? The reality is that I don't have the skillset to drive his CP car and he hates FWD in every form so it's not really the direct driver comparison that it seems.
What it may be telling you is that on a nationally adjusted basis, your class is a little soft for the region. The only real way to tell is to pack your stuff and head to nationals.
Yeah, PAX is supposed to level out the classes to make slow cars faster and show who drove best.
As with any other measurement, it really shows who can maximize the measurement best. Yes, you will have to be a good driver to win PAX. But an intelligently built car can class into a very advantageous PAX place.
People who PAX well think the system is perfect and fair, people who don't are sure it is rigged. So basically it is the same as anything else.
If you really want to see who is a better driver, ask them to drive your car.
it gives you an idea...
thing is, assumptions add up.
how far is the car from class optimal + how far is the driver from optimal + how far is lot from ideal representation + class advantage/disadvantage for lot and weather conditions
so, yeah, it gives you an idea...
Another factor of PAX that isn't talked about is the tool for the job.
If you're not running a fully prepared/setup car for the class, with the correct tires.. you're leaving time on the table.
also, courses do have some dependency where they can favor one class over another, PAX looks at averages and results of the best drivers in a class using data gathered from around the country.
If you're in a small region that lacks a lot of top level national talent.. your pax position could be not showing you what a true best time might actually be.
Case in point.. I've gotten top pax in a smaller region back in 2017. Closest I've ever gotten in a large region was top 5 in 2019. That top 5 I got in Houston was the best showing I've ever had in a large region. When I had my nationally prepped STS car in 2016 and early 2017.... my goal in Houston was to get to a top 10 in PAX. STS is a historically deep class with lots of talent and the PAX is never soft.. if you could top 10 in pax at a large autocross(which usually means it's got a lot of top level national talent) you can usually fight for trophies on the national level.
Pax is just a statistical calculator that's only as good as the data that feeds into it.
if you want to know how well you actually stand.. go to the big show in Lincoln..
Robbie (Forum Supporter) said:
If you really want to see who is a better driver, ask them to drive your car.
well said, find a person who's fast on the national level to drive your car.. ride with them.. you'll see what your car is truly capable of if it's setup properly.
I did this with Zach Sober in 2016, I was making good progress and then he got in the car with having never driven it before and beat me by 4 seconds on a 40 second course. Showed me what the true limit of grip was for the car and how much faster I could be through transitions.
Vajingo
HalfDork
3/23/21 12:23 p.m.
In reply to spacecadet (Forum Supporter) :
That's incredible dude! For the past two years I have been trying to find somebody that will drive my car that is faster than me. None of the top guys want to, and I kind of don't blame them. All of the top drivers also happened to be the club members that are there the night before setting everything up. So they are quite tired, and only want to focus on themselves, which I understand.
So I'm not 100% sure of the exact procedure for PAX, but my understanding at a high level is that it takes the performance of fast drivers at various big events, assumes that those drivers are all driving at the same skill level (and thus the differences in times between classes), and produces scaling factors to apply to times. In theory this means that if you had one of those ideal drivers drive the fastest car in every class, once you rescaled those times they would all be the same.
The biggest problem with trying to use this to compare your time to that of a top driver is that it doesn't scale each car, only the fastest and best prepped car in each class. If your car is half a second slower than the fastest one in the class because you couldn't afford the faster one, well PAX doesn't even try to solve this problem. Even if PAX was perfect it can't account for this.
The next problem is that the performance difference between cars varies by the type of course. PAX is based off numbers from big events (not sure exactly which, but national tour and the like), and big events are run on big sites. If your club only has a small site where you don't have much room for straights then horsepower isn't worth as much as it is in the big events, so the performance difference between a Mustang and Miata will likely be different. Surface type (concrete, asphalt, crumbling-used-to-be-asphalt-but-is-now-half-gravel) matters too.
Finally the assumption that all of those top drivers have the same underlying skill level and are all performing at the top of their ability is obviously only true in general terms. Some of this can be addressed by taking lots of data from lots of events and merging it together so that the errors will tend to cancel each other out, but that only goes so far.
So PAX has limitations, but used properly it will tell you some useful info. Personally I treat it as a first order approximation -- I'm skeptical that the 3 digits of precision that it includes are actually justified.
Yes, It's a rough handicap. Basically turns everything in to one spec class. It has its faults but it's generally acceptable. Best when used over multiple events, with large turnout.
If you are regularly winning pax in your region or near the top you will likely be trophy and maybe contingency worthy in national events.
As mentioned, the course can be a factor as well. The region I run with (once in a blue moon...) ran most of the events on an old airfield, so every course was a variation of, "slalom, slalom, slalom, big turn around, slalom, slalom, slalom, finish." Sounds repetetive, but the designers usually did a good job of making them as interesting as possible. That said, the courses generally favored narrow cars that transitioned/slalom well and did not favor cars with a lot of HP. Karts were usually fastest, followed by Fmod, and then various smaller cars. The PAX ranking tended to favor cars that slalom well. On other courses with more variety, the results could change significantly.
dps214
HalfDork
3/23/21 12:48 p.m.
Also raw time isn't necessarily a great indicator of anything. I've been top 5 in raw time but bottom half in pax because I was (poorly) driving a prepared class car at an event otherwise populated by st and street class cars. And there's been plenty of times when I've won my class and not been anywhere near the top of the pax list, that's really easy to do at a local event where lots of people are driving under built cars for the class they're in.
Vajingo
HalfDork
3/23/21 12:52 p.m.
In reply to dps214 :
That does bring up a good topic. My car is not built to the hilt of the rules for STR
For a while I was trying to convince members of my local club to develop a handicaped iPax to do a season long competition like a bowling league.
Basically the idea was eveyone would have their time divided by each others and averaged over the course of a season.
You would score points based on how your relative performance for this event compares to your predicted performance based on your iPAX. I set up a google spreadsheet that could of been entered real time.
The nice thing is it levelized your performance to ignore car prep and just depended on your performance relative your historic performance.
Of course immediately people where trying to figure out how to game the system by performing poorly in the begining of the season and tried to go all serious bizness on it. So because of that we never tired it. I would still love to figure it out as I think it would be fun. It seems that it appeals to the kind of people who understand how Bowling and Golf leagues work and can have fun being "competitive" with people of different skill level. The kind of people who get upset because they were beat by a bowler who bowled 145 against their lifetime average of 135 when they rolled a 220 vs their average of 240 need not apply. Of course you beat them heads up, your a better bowler, but their performance was more exceptional then yours and in the interest of making everyone have fun they "win".
I suspect that because it is comparing your performance to the "best of the day" you could likely actually have decent competition between people that don't even run at the same events (Since the points are really awarded based on your performance against yourself using the metric of others, course/weather/quality of otherdrivers are somewhat removed).
Your position in overall PAX and overall raw time is going to be pretty similar in the Street Touring classes. For every speedy HS/ES driver that beats you in PAX but loses in raw, there is an SP or P driver that goes the other way.
I look at PAX finishes over time instead of single events. If I am 2.0-2.5 seconds back on average and finish 1.5 seconds back at an event, it could be the beginning of an improvement or a one time thing. If I can't reproduce the result within the next event or two, it likely meant the course favored my car.
As an alternative to PAX, compare your raw times to RWD cars in CS/DS/FS. With minimal STR mods, you should be beating if your skill levels match. Or you could compare raw times against the fastest cars in all of Street Touring.
dps214
HalfDork
3/23/21 1:25 p.m.
Vajingo said:
In reply to dps214 :
That does bring up a good topic. My car is not built to the hilt of the rules for STR
Right, so you're never going to be at the top, but you can still use it to track progress like others have said.
aw614
Reader
3/23/21 3:14 p.m.
My Integra is screwed in either PAX numbers in the classes I run, SMF or the XS classes due to some illegal modifications it has. The mods are very minimal and the performance makes it about the same as the previous Integra Type R's that ran in STX back in the day so I just look at Raw times or compare myself to those running in STX times as a measure of performance.
Tom1200
SuperDork
3/23/21 3:21 p.m.
So we have several national drivers in our region as well as national drivers from outside the region who show up from time to time. They all Pax well.
As has been mentioned these cars are prepped to the limit of the class and the drivers are at the top of their game.
My pax times pretty much suck; 95% of problem is my car is not a top F-mod car. I need to get more seat time in the car as well.
With that said when I run the numbers from our local events and compare those with locals who go to Lincoln pax turns out to be a pretty good measure of how I stack up with my car.
I used to PAX really well in my H/S '86 Civic 1500S, fully prepped to the rules.
I would PAX very poorly in my D/M Lotus 7 replica, but: I was the only street legal D/M car, and the only Mod car that drove the 4 hours to the event.
PAX is a tool. It's not perfect, but it's close enough, for an amateur motorsport, that does not put food on your table :)
I'll use PAX to compare how I did versus people with jackets, outside of that I don't pay attention to it.
PAX, keeps you guessing till the end. Am I a better driver than that dude?
In reply to pinchvalve (Forum Supporter) :
I'm a better driver than Kevin Spacey. I know that much.
I don't even take into consideration level of prep within the class. 50% of people within a class are in it just because of one or two mods, only about 10% of vehicles within a class will be "properly prepped" with regards to having the "it" struts or coilovers, spring rates, camber settings, tires, wheel fitment, etc to be competitive. Most persons if they have the funds to prepare a vehicle fully and completely to maximize the advantage within the rule set, opt to spend the money on a different vehicle platform that starts higher up the ladder. Those who do focus on maximizing the performance of a vehicle within the rules of a class are known well enough locally that you compare yourself against them by name instead of an index. Those drivers also tend to focus on maximizing the number of events they go to a year, doing events with multiple regions, attending schools and programs and maximizing seat time. So even then the commitment is there more so than it is with those who they compete with and that generally makes as much of a difference if not a greater difference than vehicle prep.
But proclaiming that you're underprepared within a class, when half of those who are entered in the class are as well, is nothing more than a racer's excuse and a poor one at that.
Tom1200
SuperDork
3/23/21 10:48 p.m.
captdownshift (Forum Supporter) said:
But proclaiming that you're underprepared within a class, when half of those who are entered in the class are as well, is nothing more than a racer's excuse and a poor one at that.
I'm the only F-mod running locally but even it it wasn't, it's a 33 year old car, with an obsolete motor (manufacturer no longer in business) that's down 20 horsepower compared to the Rotax engines. So not a poor excuse at all.
I just bought a stash of Rotax engines so I want have the motor as an excuse to much longer. LOL
nocones said:
It seems that it appeals to the kind of people who understand how Bowling and Golf leagues work and can have fun being "competitive" with people of different skill level. The kind of people who get upset because they were beat by a bowler who bowled 145 against their lifetime average of 135 when they rolled a 220 vs their average of 240 need not apply. Of course you beat them heads up, your a better bowler, but their performance was more exceptional then yours and in the interest of making everyone have fun they "win".
Yeah, I don't think that's ever going to fly with autocrossers... Autocrossing is SERIOUS BUSINESS!