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Phone
Jul 30, 2005

親子丼をほしい。
Depends on how you feel about the fuel tank/pump being exposed?

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Suburban Dad
Jan 10, 2007


Well what's attached to a leash that it made itself?
The punchline is the way that you've been fuckin' yourself




I'm failing to see a pro, here.

The Prong Song
Sep 7, 2002


WHITE
DRIVES
MATTER
^^^ Pro is that I don't have to buy another one and then hack it up to install a different rollbar than the one the PO has in.

Phone posted:

Depends on how you feel about the fuel tank/pump being exposed?

Second Gen. Not the bit that covers the fuel tank and pump. The other aluminum bit - the one ordinarily hacked up to install a rollbar. Parts catalog calls it a "parcel shelf bulkhead".

The Prong Song fucked around with this message at 20:37 on Mar 5, 2018

BlackMK4
Aug 23, 2006

wat.
Megamarm
I think I'm kinda starting to realize what my car does on the limits of steady state adhesion and am kind of getting more comfortable with it. If I come into a fast, longer corner as quickly as I can the car will feel like it's slightly pushing the front by mid corner so I'll get back into the gas (not just maintenance throttle) to leave and it'll slightly tighten it up if I find the balls to get into it more than a comfortable amount or add more steering, otherwise I'll end up on the curbing of the exit area. I've started noticing if I follow some of the quicker Miata guys their cars are pretty much doing the same thing and they seem t be really tidy drivers. Should I try adding more rear bar, finding more throttle balls, growing balls to rotate the car more on entry? What should I be shooting for the car to be doing? I think it opens my eyes as far as the balls on people whose cars oversteer in this situation.

The car will really only spin if I try to carry in too much speed and heavily unsettle the rear of the car over curbing by mistake, if I flick it too hard on a quick transition with the back end light (think S turn), or if I heavily trail brake too deep.

I guess it's time to seek out instructors.

BlackMK4 fucked around with this message at 23:39 on Mar 5, 2018

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull
I mean, more throttle? Maybe I'm tired from work though, it's sounding like you're talking about taking corners at a constant speed or something.

BlackMK4
Aug 23, 2006

wat.
Megamarm

1, 5-6-7

2, 3, 4-5, 6-7

I feel like I can carry enough speed into the mentioned corners that it seems like I am kind of pushing the front by mid corner and trying to make sure I'm not running off the edge of the track by exit.

BlackMK4 fucked around with this message at 00:35 on Mar 6, 2018

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull
5-6-7 on that first one is a pretty special case corner... I guess I just tend to not like adding rear bar as a first resort, though checking my notes, going to have to on the MX-5 because we're not allowed as much camber as it really wants.

Sex Weirdo
Jul 24, 2007

Has anyone done the SCCA/Tire rack track night in america? Is it a worthwhile program or should I be looking more at full trackdays? This would be my first real track driving experience and I would be in a street driven daily driver car.

jamal
Apr 15, 2003

I'll set the building on fire
Yes more rear bar or spring rate will make the car closer to neutral at steady state, but as you're seeing, throttle takes out understeer because you're adding rear slip angle. If the car was perfectly neutral mid-corner, then you're not going to be able to add power as early at corner exit. We always kept the rear softer on rwd cars because it seemed to allow better corner exit speed.

Also, get a tire temp probe.

BlackMK4
Aug 23, 2006

wat.
Megamarm

jamal posted:

Yes more rear bar or spring rate will make the car closer to neutral at steady state, but as you're seeing, throttle takes out understeer because you're adding rear slip angle. If the car was perfectly neutral mid-corner, then you're not going to be able to add power as early at corner exit. We always kept the rear softer on rwd cars because it seemed to allow better corner exit speed.

Also, get a tire temp probe.

Roger, roger on the temp probe. :v:

I've noticed what you're saying, it seems like I can get on the throttle a lot earlier than other S2000 people without the rear getting loose (we have a fair group of 8 semi-regulars). It seems like my car is set up with a higher-than-normal front bias in terms of springs / roll bar stiffness, but it works for me and now I'm afraid to mess with it because I have no idea what I'm doing. I've had other people say my car shouldn't work based on rates. :v: Where do I start the learning process (other than getting a temp probe)?

BlackMK4 fucked around with this message at 04:12 on Mar 6, 2018

HandlingByJebus
Jun 21, 2009

All of a sudden, I found myself in love with the world, so there was only one thing I could do:
was ding a ding dang, my dang a long racecar.

It's a love affair. Mainly jebus, and my racecar.

Sex Weirdo posted:

Has anyone done the SCCA/Tire rack track night in america? Is it a worthwhile program or should I be looking more at full trackdays? This would be my first real track driving experience and I would be in a street driven daily driver car.

Do it. You're not going to get real track time for cheaper. I love TNiA.

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull

BlackMK4 posted:

Roger, roger on the temp probe. :v:

I've noticed what you're saying, it seems like I can get on the throttle a lot earlier than other S2000 people without the rear getting loose (we have a fair group of 8 semi-regulars). It seems like my car is set up with a higher-than-normal front bias in terms of springs / roll bar stiffness, but it works for me and now I'm afraid to mess with it because I have no idea what I'm doing. I've had other people say my car shouldn't work based on rates. :v: Where do I start the learning process (other than getting a temp probe)?

First off, there's problems with being a one man band in terms of driving and trying to be race engineer. It's hard to tune based solely on impressions because there's a bunch of causes for handling issues, some of which are driver mistakes and also some of it is going to be flaws in the handling the driver's covering up for. Data acquisition, even an AIM Solo or phone timer thing is really helpful. The nice thing about the AIM is there's a better chance of finding other people to compare data with.

I'm not claiming to be a driver coach or a fantastic driver, I'm just trying to explain what I've been doing. I'll try to give a concrete example I'll bring up is theT4 MX-5 my dad and I run and that I ran at Road America for my first time there last year. First, you really have to try to sort out things the driver's not doing right - for example I had a few incidents of running out of track at the exit of turn 5 because it's the big downhill straight, I was braking too early, taking too early of an apex and had to run too tight of a radius turn to actually make the corner.

So, basic driver mistakes aside, some corners cars will just handle better than others. Again at Road America, the carousel the car just starts pushing, and any attempt to use more throttle just makes it push more. Tire temperatures and wear patterns show that the front left tire is getting cooked a lot more towards its outside shoulder - actually hotter on the outside shoulder which should never be the case in an ideal world. So the simplest would be to just add more camber if class rules allowed, but in our case we may be at the limit. If we can't, or say if temperatures were looking better, I'd try more rear bar and hope that it helps corners like that more than it hurts everywhere else. The fun part is that any change may mean needing to make driving changes to compensate for side-effects - later apex to work around it possibly being more tail-happy in low speed corners for example.

Data acquisition lets you look at individual corners after changes and actually quantify where changes of one sort or another are helping or not... if you're losing more time in corners that aren't helped by a change than you're gaining in ones are helped, you should rethink that change, you know? Once you start getting to more advanced systems you can do things like feed steering wheel position, brake position and throttle position in, which starts telling you what the driver is actually doing to respond to things; feeding in more steering to compensate for push, easing off gas due to some upset, things like that. More advanced stuff you can start directly measuring what the car is doing in response to more quickly sort out why it's behaving a given way... which is pretty much why I'm trying to figure out the lowest cost way to have a thorough data system.

Blaise
Sep 10, 2003

Sex Weirdo posted:

Has anyone done the SCCA/Tire rack track night in america? Is it a worthwhile program or should I be looking more at full trackdays? This would be my first real track driving experience and I would be in a street driven daily driver car.

No. Here's part of what I to SCCA:

quote:

there were serious safety concerns on track last night. I understand that SCCA does not have the budget to put instructors into all (or even most) cars for the event. However, there needs to be a much more comprehensive explanation of how point-bys work. More than half of the group in intermediate did not know how to point somebody by and kept giving pointbys in very dangerous places to pass. Intermediate group should have mandatory post-session meetings to explain what it means to give a point by and where the line is and how to point somebody by OFF line. We need to have an opportunity to explain this to everybody in the group if there is an issue instead of having to walk around the paddock and explain it to each person individually.

May I suggest a system in which more experienced drivers (I have 40+ days) can be registered as an instructor for their friends? I was able to do this earlier this year just to help my friends understand where the line was and how to handle traffic. I would even be happy to volunteer for random folks provided we can make the event SAFE. I am shocked we haven't had a wreck that has closed down the event permanently.

Next, we had an exocet that was broken at the end of the bowl headed into the front straight - I went a full lap before we got a black flag. No yellow went out either, so it was more than a bit of a surprise to come onto doing 80+ coming out of the bowl. This was a corner worker issue and not SCCA's fault, but it was not pleasant.

Worst of all, the black FD RX-7 spun twice in front of me (once after passing without a point) and was doing literally under 60mph on the front straight with his arm out the window (no obvious point-by) as he was off line, causing lots of confusion. I took it upon myself to alert both SCCA and track officials to pull him off track. He had no business being on a race course outside of beginner group with an instructor on board. Why didn't SCCA or the track notice this? There were at least 5 cars in my group who would have been sent home in a comparable NASA event immediately, and at least a dozen who needed serious help.

I am likely not going to be attending track night again nor will I be recommending it to friends. If you guys can't figure out a way to keep safety a priority and the convertible policy clear - it's going to be difficult to have fun. I am insulted that my friend was removed from the track for no clear reason while others who were being unsafe on track were able to continue to attend.

It's a pretty serious poo poo show. Basically take a track day, remove ALL instruction (in or out of car), and let people sign up for any group they want. Especially as a noob, you want to be on track with an organization that will put a competent instructor in the right seat.

NASA all the way (or Chin I hear is also excellent). Every sketchy situation I had on track was during the few Track Night events I did... I thought I wouldn't be able to say no to the price, but you really shouldn't be putting yourself into a dangerous situation to save $100. It's a great concept on paper but it doesn't work in practice.

Aside from this event above, I had an e46 push me into the grass on the front straight at NJMP-T after I gave him a point by. He took the pass then CUT ME OFF - and had the balls to tell me in the paddock that I had to lift to let him by. I'm my stock 1.6 miata I have to lift for your BMW? That's not how that works. Make the pass, stay off line going into T1 if you can't get a few cars of space before the braking zone. In another event I gave a BRZ a point into the bowl at Lightning and he didn't know what to do... I couldn't see him (I have a halo seat) in my blind spot and just stayed off the gas, off the gas, off the gas.... afterwards he told me he didn't know what to do. There's just SO much confusion and lack of experience combined with instruction that it makes for a weird time.

In comparison, (I posted this a few pages back), I spent all of '17 doing basically every NASA event on the east coast. In a season I made it to advanced group and will never forget the first time I hit T1 on summit in traffic.

1. Wide open going down straight, doing 105mph. Give TT RSX a point by on my right.
2. RSX passes going 115+, ALSO with his arm out the window pointing to the right.
3. Corvette blows past BOTH of us like we're standing still.
4. Laughed out loud the whole way through turn 1, with the Vette on the far inside, RSX doing mid entry and me from the traditional line. It was seriously perfect. Makes all the time spent learning worth it.

Blaise fucked around with this message at 14:58 on Mar 6, 2018

jamal
Apr 15, 2003

I'll set the building on fire
Yeah I haven't really figured out the best way to take odb data, extra gauge data, gps, and accelerometer data without spending money on an actual datalogger. There must be some cheaper diy way though.

For off the shelf stuff, AEM's aq1 is a good option. They have a version that comes with an ODB connector and if you use aem x-series gauges it will log them via the aem-net can system which doesn't take up the standard inputs. Then all you need to add is the gps antenna. Cost for the aem aq1 odb and a gps receiver is somewhere around 650.

Racepak has a small basic logger that is battery powered and connects to a phone. Most basic setup is plug it into the odb port, stick the gps antenna on the roof, and connect via bluetooth. Cost is in the 600 range. I think your phone has to be hard mounted as it uses that for an accelerometer.

If you're going to have a digital dash, some of those have logging built in. So you can take odb data, add extra sensors, and log all from one place. But you're looking at like $1500 to start. However, if you start with a logger, then add extra sensors, then add a display, you're going to wind up in the same ballpark.

jamal fucked around with this message at 19:07 on Mar 6, 2018

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull
Next season we're trying an AIM SoloDL, which on the NC MX-5 should have a lot of interesting data.

For the EProd car and later I'm honestly torn between an AIM Evo4S or rolling my own. It doesn't seem like AEM has any good way of doing what I want for long term, which is 4 1khz analogs for shock pots, a metric fuckload of lower speed analog-or-CAN stuff, and some sort of dash. Rolling my own really really really would be cheaper, but it gets to questions of whether I'll get around to it and if I can avoid going crazy from doing my own analysis instead of just using AIM's.

I think there's probably not many who would have the faintest idea what to do with 60-some channels of data, mind. ;)

heffray
Sep 18, 2010

Track Night in America has been well-run with a good focus on safety in the Seattle and SoCal areas: passing zones and required point-bys are strictly adhered to (marked straightaways only for Beginner & Intermediate, Advanced allows point-bys in other areas), and I'd recommend it to anyone looking for track time that already has some understanding of how to drive and behave on a track. The lack of in-car instruction means it wouldn't be my first choice for a complete novice, but I'd think some GT or Forza and a few autocrosses would be a good idea before a track day even with instructors. Also, most of the cars at TNiA are street cars if not DDs: make sure your car is safe and your brakes & tires can handle some heat, but you don't need to do a ton of prep.

I'll be running with SCCA TNiA again in a couple weeks for Big Willow on 3/15, just waiting on Tire Rack / UPS to deliver my new wheels & tires: stock asymmetric staggered RE050s aren't awful, but the outside fronts are getting pretty beat up and I can't rotate them in any useful fashion. I'm pretty sure the 18x9.5s and 275/40-18 RS4s on their way will make this better, or at least give me more shoulder areas to kill before buying more tires.

TrueChaos
Nov 14, 2006




heffray posted:

18x9.5s and 275/40-18 RS4s on their way will make this better, or at least give me more shoulder areas to kill before buying more tires.

I'm basing this off my (limited) tire knowledge on the miata, but I think you've got too much tire for the wheel. I run a 245/40/15 RS4's on a 9, which seems to run squareish. I know 225/45/15's run slightly stretched. I've found that the extra 20mm hurts my top speed at the track, but helps at autocross. 275's on a 9.5 seems like a lot of tire for the wheel.

Also, you will wear the outside shoulders a lot quicker than the rest of the tire. With -3.2 degrees up front and -2.8 degrees in the rear the inner shoulder of the tire looks untouched compared to the outer shoulder. Front/rear appear basically the same wear wise, and I'm getting a decent temperature distribution across all tires (usually outer hottest, center ~5-10F down from outer, inner ~15-25 down from outer).

BlackMK4
Aug 23, 2006

wat.
Megamarm

mekilljoydammit posted:

First off, there's problems with being a one man band in terms of driving and trying to be race engineer. It's hard to tune based solely on impressions because there's a bunch of causes for handling issues, some of which are driver mistakes and also some of it is going to be flaws in the handling the driver's covering up for. Data acquisition, even an AIM Solo or phone timer thing is really helpful. The nice thing about the AIM is there's a better chance of finding other people to compare data with.

I'm not claiming to be a driver coach or a fantastic driver, I'm just trying to explain what I've been doing. I'll try to give a concrete example I'll bring up is theT4 MX-5 my dad and I run and that I ran at Road America for my first time there last year. First, you really have to try to sort out things the driver's not doing right - for example I had a few incidents of running out of track at the exit of turn 5 because it's the big downhill straight, I was braking too early, taking too early of an apex and had to run too tight of a radius turn to actually make the corner.

So, basic driver mistakes aside, some corners cars will just handle better than others. Again at Road America, the carousel the car just starts pushing, and any attempt to use more throttle just makes it push more. Tire temperatures and wear patterns show that the front left tire is getting cooked a lot more towards its outside shoulder - actually hotter on the outside shoulder which should never be the case in an ideal world. So the simplest would be to just add more camber if class rules allowed, but in our case we may be at the limit. If we can't, or say if temperatures were looking better, I'd try more rear bar and hope that it helps corners like that more than it hurts everywhere else. The fun part is that any change may mean needing to make driving changes to compensate for side-effects - later apex to work around it possibly being more tail-happy in low speed corners for example.

Data acquisition lets you look at individual corners after changes and actually quantify where changes of one sort or another are helping or not... if you're losing more time in corners that aren't helped by a change than you're gaining in ones are helped, you should rethink that change, you know? Once you start getting to more advanced systems you can do things like feed steering wheel position, brake position and throttle position in, which starts telling you what the driver is actually doing to respond to things; feeding in more steering to compensate for push, easing off gas due to some upset, things like that. More advanced stuff you can start directly measuring what the car is doing in response to more quickly sort out why it's behaving a given way... which is pretty much why I'm trying to figure out the lowest cost way to have a thorough data system.

Thank you for this. :) I do have an AIM Solo, but it's a non-DL so I'm pretty limited in terms of what I've got to work with. Goddamn is their software terrible to use, marking corners is really difficult, marking corners sometimes breaks the split times, and you're kind of flying blind unless you can match sector time sections up across video. Maybe someone has some helpful tips for using RS2 though. It's probably worth flipping my Solo for a Solo DL.

Example: Splitting of corners goes terribly, at best, and it's kind of difficult to see what's going on with no throttle/brake graph along side.


BlackMK4 fucked around with this message at 01:51 on Mar 7, 2018

net work error
Feb 26, 2011

This is a good place to ask. I spent some time on a track this past weekend and was trying out RaceChrono for Android. It's only the free version but I noticed I can export to .vbo format. What's a good program to take this data and make some sense of it and see how to improve and stuff?

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull
Yeah, it's kinda counter-intuitive and correlating it with video really does make it easier. And yeah, there's a reason I bought a DL for my dad for Christmas... a month before the Solo2s were announced, lol.

OK, some cool stuff to look at. First off, go to the lap manager tab, right click and go to "disable lap" for in and out laps - it screws up figuring out sectors from that.

All the cool graphs are under the "view" menu - GPS gives you a graph with color shaded by whatever channel you want - click on the color spectrum label to switch channels. You can also do interesting things under the "modify" menu with math channels - if you open the default set you can see things they did. The GSum one is the magnitude of lateral and longitudinal acceleration, though the variables it uses by default aren't the Solo's GPS lateral and longitudinal accelerations; shows you about where you are on the friction circle.

Split times highlights your best sector times like I was talking about and actually computes a theoretical "best" lap from the data. You can then look at that sector and start looking at where G onset is to figure out braking points and stuff in the absence of real brake and throttle data.

There's tools to sync the displays with video, and for that matter, come up with a video of your hypothetical "perfect" lap too but I've not gotten too far into that side of things. The nice thing about AIM's overpriced video setup is that it syncs automagically.

Dave Inc.
Nov 26, 2007
Let's have a drink!
Okay so I managed to get the gopro a little higher up for a better viewpoint at Roebling. I know I can carry more speed into turns one and six, but going from a Ventus RS4 down to a Continental Extremecontact sport left me feeling pretty squidgy under braking and corner entry so I had a hard time working up the balls for trail braking. There's a few seconds out there for corner entry speeds, but I wonder what other tips you all might have.

https://www.youtube.com/watch?v=zg8-m2ffonQ

I need to find what a 911SC is comparable to in lap times so I can get a feel for how much time I'm leaving out on track.

Edit: Oh and I'm at 1/1.5 camber, definitely need more but I'm at the mechanical limit for the front end. How far down the rabbit hole do I want to go on springs, sways, camber plates....

Dave Inc. fucked around with this message at 14:26 on Mar 7, 2018

Suburban Dad
Jan 10, 2007


Well what's attached to a leash that it made itself?
The punchline is the way that you've been fuckin' yourself




mekilljoydammit posted:

I think there's probably not many who would have the faintest idea what to do with 60-some channels of data, mind. ;)

Will you? :v: I realize you're an engineer and love data (same, I get this), but with this plan it's going to be a colossal amount to comb through. Most of which you won't be able to reasonably look at and make use of, I'd guess. It would be good for trying to figure out an issue with a specific corner or whatever to try and improve, but I feel like you're never going to be able to min/max everything like this as a one man (or two) show.

Phone
Jul 30, 2005

親子丼をほしい。

net work error posted:

This is a good place to ask. I spent some time on a track this past weekend and was trying out RaceChrono for Android. It's only the free version but I noticed I can export to .vbo format. What's a good program to take this data and make some sense of it and see how to improve and stuff?

Did you have an external GPS hooked up to it?

If you didn't, then the only data worth looking at is lap times.

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull

Larrymer posted:

Will you? :v: I realize you're an engineer and love data (same, I get this), but with this plan it's going to be a colossal amount to comb through. Most of which you won't be able to reasonably look at and make use of, I'd guess. It would be good for trying to figure out an issue with a specific corner or whatever to try and improve, but I feel like you're never going to be able to min/max everything like this as a one man (or two) show.

Truthfully? Despite how I'm making it sound, it shouldn't actually be that bad, because the whole point is to build models and systems to do the grunt work. I'll break down the basics of my balls out ideal because I'm still at "drink coffee" stages of work and this poo poo is really interesting to me.

So, a decent chunk of the channels would be under the broad category of diagnostics - engine temps and pressures, trans fluid temp, diff temp, egt, etc. That's mostly there for lighting an idiot light, post mortem failure analysis, and figuring out if you need to adjust cooling airflow. Brake rotor temp feeds into that too and also helps with pad selection but it's not an area of too much subtlety.

Next, tire temp and pressures - the available IR thermopiles tend to have something like an 8 pixel wide sensing stripe, and I'm not intending the sensors to move with the tire, so basically imagine a fairly simple routine to, after the stuff is recorded, figure "OK, the edges of the tire are here, the inside shoulder, middle, and outside shoulder are this, that, and that other one". Those and pressures... on track, get processed into a "cold tire" or "leaking tire" warning if out of bounds, between sessions get processed into guidelines of looking at adjusting camber or pressures, and between events feed into tire models. I'll get into the "between events" grade stuff later.

Platform control, which is to say shock pots and ride height sensors... between sessions, shock pots get processed to a histogram which you can use for clickers, and ride height to warnings about bottoming... between events, vehicle dynamics model. Wheel speeds get to warnings about lockup/wheelspin and suggestions about brake bias, but are mostly, again, vehicle dynamics model stuff. All the rest of it basically turns into a better correlated version of AIM data - yaw rate looked at through variances between a couple of accels in adition to a rate gyro, driver inputs looking at what the nut behind the wheel is trying to do, but how to deal with it is pretty cut and dried.

So on-track, you get some feedback if the tires are working yet, if you should turn the brake bias knob maybe, and a more comprehensive idiot light. At the track between sessions, you basically end up with a lot of the basic AIM things about what sector was fastest on what lap, plus some extra stuff on maybe adding more tape, playing with camber or pressures, or turning a shock clicker.

The end goal is the vehicle dynamics model. Once you relatively accurately model the car, you can use it to start coming up with a tire model - the car model plus the data you have tells you the orientation of each tire relative to the ground and how much force is going into each tire, so you can come up with a model of resulting grip at that force, orientation, temperature and pressure. Well, now that you have a relatively validated model for tire behavior, you can take it the other way and change stuff on the vehicle dynamics model to test what effects it has - it's not too hard to come up with a track map and find a racing line around it (throw a bunch of iterations on braking points and stuff to find an "optimal" one) and then do that for a bunch of iterations on car setup.

... which won't be perfectly accurate even with perfect data, before anyone puts words in my mouth. But the point is to come up with a tool to quickly sort through every potential thing that could be changed to come up with a narrower list of things to test on track, plus figure out other things like "in this weather conditions, with this many heat cycles on this compound, what should my starting pressures be?"

Maybe it's all ambitious, but most of the components of doing that are fairly cut and dried, and for that matter it's all been done before.

net work error
Feb 26, 2011

Phone posted:

Did you have an external GPS hooked up to it?

If you didn't, then the only data worth looking at is lap times.

Yeah it was just the phone GPS. But assuming I upgraded and had an external GPS what would your recommendation be?

Phone
Jul 30, 2005

親子丼をほしい。

net work error posted:

Yeah it was just the phone GPS. But assuming I upgraded and had an external GPS what would your recommendation be?

For data analysis or a GPS?

If you have data with just the internal phone GPS, the only usable data is the lap time +/- .5s. If you have a 10Hz GPS, you can export out to csv or vbo or whatever else (like to sync with Race Render for overlays) and start breaking the track out into sectors. I have only used RaceChrono in app for checking against various lap times or combining it with friends' data so we could see who was faster where. I'm not sure of any of the analytic suites that might exist, but RaceChrono is more than welcome to hand over the data.

That (unhelpfully) said, the user/RC generated traps only have a handful of sectors out of the box. Drop # of turns/2 sectors onto the map so you can start to get an idea in car and post session analysis to see where you're gaining or losing time. Having a trap at the edge of a braking zone or on the exit of a corner really narrows down what needs improvement because what feels fast is different than what is fast.

BloodBag
Sep 20, 2008

WITNESS ME!



I have some solo class rules for e street questions for you fine gents.

1. I have a 1995 M edition miata that came factory with a torsen LSD, does this bump me to STR? Or is this part of the special edition rules that allows the R miatas into this class?

2. The seats are absolutely hammered and since mazda only made them one year (3500 sets) they are $700 for a set that is in ok shape. Could I swap NB seats into the car and stay class compliant? (would changing the seats take away one of the things that makes it an M edition and therefore I would no longer be in the special edition exemption for the LSD?)

I feel like I'm trying to suss out M:tG stack rules with some of this stuff.

Phone
Jul 30, 2005

親子丼をほしい。
Are your local clubs a bunch of dicks? If someone protests you for having surfboards in a 95M, take a poo poo in their washer bottle. The torsen is factory equipment, it's fine.

Street rules:
- Factory sized wheels (+/- 1" diameter)
- 180 or 200TW DOT tires
- Shocks are open
- One aftermarket sway bar

The Prong Song
Sep 7, 2002


WHITE
DRIVES
MATTER

BloodBag posted:

...solo class rules for e street questions...
http://www.racershq.com/street-class-autocross-win-just-3-mods/

BloodBag
Sep 20, 2008

WITNESS ME!



I've got a fresh set of BFG sport comp 2's (340tw, 195-50-r15) on there, 15x6 wheels and an offset that puts me just under the max of 7mm from factory. The suspension is original with 1994 dates on the struts. I'm leaning towards starting off with KYB GR-2's since I'll be more tooling around than racing this thing. If the koni sports are worth it then I'll keep saving for them. Everything else I've done has been with the mind of keeping it class legal in ES. The seats just bug the hell out of me and all other NA seats are trashed by now too seemingly. If I could score some NB surfboards for farting around and then drop the original headrest seats in it to race, then so be it.

Phone
Jul 30, 2005

親子丼をほしい。
Drop in some Bilsteins or Koni Yellows and don't forget to replace your bumpstops.

BloodBag
Sep 20, 2008

WITNESS ME!



Phone posted:

Drop in some Bilsteins or Koni Yellows and don't forget to replace your bumpstops.

I was gonna get the goodwin 58/58 red white stock class ones. Or should I do some others?

E: I greatly appreciate the input!

jamal
Apr 15, 2003

I'll set the building on fire
Yeah no on the gr2. yes on bilstens or konis. Konis get you a knob to turn which can be useful or might just have you going in circles on what to do with them. Downside is it is like twice as much.

I'd offer to get you a set of bilsteins but my distributor shows them on order with a delivery date in may-june. So you'd want to make sure that whoever you bought them from actually had a set in stock because it seems bilstein usa doesn't right now.

The Prong Song
Sep 7, 2002


WHITE
DRIVES
MATTER

FatCow posted:

Finally went over the car to see what I need to do in order to be ready for this year. In addition to changing all the fluids I had to re grease 2 of the sliders on the brake calipers. And they said Miata's were low maintenance. :/

My rear hubs are pretty much past their service life, but I'm hoping to stretch them until I have my garage built

Are you coming to VIR this weekend?

FatCow
Apr 22, 2002
I MAP THE FUCK OUT OF PEOPLE
Probably. I'm nursing a cold that started Monday afternoon right now. If it's not too terrible I'll still go. I'll still be in PTE 146.

The Prong Song
Sep 7, 2002


WHITE
DRIVES
MATTER

FatCow posted:

Probably. I'm nursing a cold that started Monday afternoon right now. If it's not too terrible I'll still go. I'll still be in PTE 146.

Well, I signed up and have had this planned since they announced the start of the season but drat if I think it's going to be a great time. High of mid-40s, rain on Saturday and snow on Sunday?

I'll keep an eye out for you. I'm bringing the new/old Miata from now until the foreseeable future, look for the one that's every color.

Wrar
Sep 9, 2002


Soiled Meat
Wife, friend and I did one of those supercar experience things and now she wants to do racing school. Any of my fellow VIR area goons have recommendations? As much as I would love to do a rally school, road racing school will get us more seat time because VIR is a little over an hour away. Just not enough events in the dirt.

Phone
Jul 30, 2005

親子丼をほしい。
I'd just do a bunch of DEs with local clubs to get seat time. vOv

FatCow
Apr 22, 2002
I MAP THE FUCK OUT OF PEOPLE
HPDE would be your best bet if you have a car that can be tracked. No idea if you don't have a car. I can't think of any 'arrive and drive' schools at VIR.

THSCC and BMWCCA run the best schools. THSCC will be back there in September, BMWCCA in June and September.

NASA also runs driver schools they'll be there in May, August, and October.

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Salami Surgeon
Jan 21, 2001

Don't close. Don't close.


Nap Ghost
Bertil Roos comes to VIR sometimes. Looks like it's not on the schedule this year though.

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