The Good, the bad, and the ugly

[claudermilk]

Ok, really mostly bad & ugly.

Two events to post on since I got behind and had a vacation between.

July 6th autocross, El Toro.
This was a fairly quick course and I ran into the rev limiter a couple of times. I guess I'm getting quicker now that I am seeing the problem with running 3.73 gears on an autocross? I suspect 3.55's are somewhere in my future. The course did have a few nasty little tricks in that you were sent into several slalom elements going the "wrong" way and the elements following did the same, making entry and exit more challenging.

As my second event after installing the suspension parts, I'm still playing with settings. I was also playing with getting my telemetry/camera setup dialed in and had issues with that (to the point I completely missed the best run of the day...sigh). I also had convinced a co-worker to try out autocross in his Golf R32; he had a blast and I think will be coming out again.

While my driving wasn't great--I'm definitely among the "hack" contingent around here--it wasn't awful. The second camera shows me I am not too bad on the cones I want to get close to. I seem to only be giving away 6" or so this day.

So, the videos:




July 20th autocross, El Toro.
Probably one of my worst showings in a while. I'm still playing with the Koni settings and I seemed to keep going in the wrong direction; I need to get out to a practice day & flog the car with many different settings to get a better feel for it. I know I overshot trying to balance the car & get a touch of overteer dialed back in--I got lots. Right now me tuning the suspension = and That said, after watching other high-HP RWD street cars I was not alone. Perhaps the windy conditions got the surface nice & dusty as I was not the only one struggling with the rear end. Lots of oversteer & spins during the afternoon. I guess as bad as I did, I at least wasn't "that guy"--a noob Miata driver was aiming at the workers on the slalom & I got to that station early enough to witness this & have to run away from the car. Scary.

The nice thing about running on old runways, is there is lots of space to play with. This was another pretty open, fast course and I ran into the rev limiter again. It also had the longest slalom section I've ever seen. I think I got the basic line and tricky parts figured out, I just never executed--even after 4 (!) reruns. With all that practice, I should have done better; in the end on the final run of my group a Camaro--the only other car in CAM in the results--just beat me. He did take mercy on me & point out my tires sucked vs his; yes, if I was running 200 treadwear tires, I'd likely have a second or two on him.

As bad as my showing was, I have gotten better at my spacing off the apex cones. I need to get more consistent, as predictive timing was showing fast times on runs 2 & 4 before I blew those runs.

I am getting dealing with the cameras & telemetry dialed in. Just ran out of battery on one camera--I probably need a new one & some spares. I have to say the new RaceChrono Pro app is very nice. Once you have defined the start and finish lines, and have your BT devices defined it's set & forget. I have added the Garmin GLO GPS and ScanTool MX to the repertoire and the app uses them without a hitch. Now to learn how to use that data. For now, the app's new predictive timing is nice--big green box on screen & I'm doing better, big red box & I need to hustle and find some time. Oh, and yes, the roof cam settings were borked and since fixed. No more 4:3 720p.

The videos for your amusement


First time I've completely lost the car & spun it. Bleh. This was a fast run, too.



For my suspension settings, I am starting out about 1 turn from stiff in front and about 1.5 turns in rear. I'm thinking just even them out & start from my street setting of 1 turn from soft and bump 1 turn at a time and see how it does. I am starting to wonder if I need to grab some adjustable swaybars to tune the front-to-rear balance. I'll definitely play with settings on the Konis before throwing more parts at it, though.

 

[kcbrown]

Aaaand.... now you know why I want to compute new spring rates that will retain the same suspension force balance that I already have. It's also why I'm not doing squat to the suspension geometry.

It might not work, of course, but I can't think of any other way to get an end result that is likely to be close to how the car already behaves. I like how the car already behaves.

 

[claudermilk]

LOL I knew going in that I'd be struggling for a bit. I wanted less oversteer than stock; initially it seemed I took it all out & just plowed. Now I'm dialing in too much. Eventually I'll get it sorted.

 

[kcbrown]

LOL I knew going in that I'd be struggling for a bit. I wanted less oversteer than stock; initially it seemed I took it all out & just plowed. Now I'm dialing in too much. Eventually I'll get it sorted.

I suspect that dialing out understeer/oversteer is a tricky thing to do, because my (limited) experience is that the degree to which it shows depends on the characteristics of the corner you're putting the car into. You might, for instance, get more understeer on a more gradual corner and more oversteer in a tighter corner. Or it might be the other way around.

This is one of the reasons I'm rather hesitant to modify the suspension at all.

At least with coilovers, I can get very close to the stock suspension's spring rates if I want to, and I'll still have better dampers than stock, so it should wind up being an improvement even if the experiment with higher spring rates fails miserably...

 

[csamsh]

I suspect that dialing out understeer/oversteer is a tricky thing to do, because my (limited) experience is that the degree to which it shows depends on the characteristics of the corner you're putting the car into. You might, for instance, get more understeer on a more gradual corner and more oversteer in a tighter corner. Or it might be the other way around.

This is one of the reasons I'm rather hesitant to modify the suspension at all.

At least with coilovers, I can get very close to the stock suspension's spring rates if I want to, and I'll still have better dampers than stock, so it should wind up being an improvement even if the experiment with higher spring rates fails miserably...

The tricky thing is figuring out when and why you're losing balance, mostly whether it's during a dynamic or static load situation, and what weight transfer (if any) is happening during your traction event. Once you do that, correcting it is easy. There are really only three things that we can practically change to affect under/over steer:
-wheel rate
-dampers
-right foot

Whether you do that with spring rate, bar rate, tire pressure, rebound, or compression adjustments is up to you....read Neil Robert's book- he makes the damper adjustment thing pretty easy actually.

http://www.theoryinpracticeengineering.com/resources/dampers/neil roberts Racing Dampers 202.pdf

The wheel rate is also "easy"- remove stiffness from the end that loses grip, unless you need that stiffness to go faster, in which case you need to make the other end stiffer.

There's of course "more to it" than this...but this will get your car settled at an autox or track event...just watch your times to see if the adjustment was good.

 

[kcbrown]

The tricky thing is figuring out when and why you're losing balance, mostly whether it's during a dynamic or static load situation, and what weight transfer (if any) is happening during your traction event. Once you do that, correcting it is easy. There are really only three things that we can practically change to affect under/over steer:
-wheel rate
-dampers
-right foot

Whether you do that with spring rate, bar rate, tire pressure, rebound, or compression adjustments is up to you....read Neil Robert's book- he makes the damper adjustment thing pretty easy actually.

http://www.theoryinpracticeengineering.com/resources/dampers/neil roberts Racing Dampers 202.pdf

The wheel rate is also "easy"- remove stiffness from the end that loses grip, unless you need that stiffness to go faster, in which case you need to make the other end stiffer.

There's of course "more to it" than this...but this will get your car settled at an autox or track event...just watch your times to see if the adjustment was good.

I'm not at the point where I can use times to determine what adjustments to make. I'm simply not that consistent.

But then, that presumes that it's speed I'm after. What I'm actually after is ease of control, because that is what makes the car the most fun for me. I guess another way of saying it is that I'm after maximum handling flexibility (while driving. Adjustment is a separate thing. I'm talking about things like being able to get understeer or oversteer at will, and being able to easily control how much of each you get), while retaining or improving on the stock ride quality (which should be possible to do, as it's overdamped in compression as it is).

Autocross is going to be the best venue for testing that. This is why I'm going to put coilovers on the car sometime in October: I have an Evolution driving school in November, and it'll be the perfect venue for testing the changes I've made.


There are certain things I'm not going to compromise on, like ride height. I like it basically where it is (the front could use a 1/4" drop for aesthetics, maybe 1/2" at the most, but no more than that), and I have daily driving practical reasons for that, along with suspension geometry reasons. I've also gotten used to the look it has and don't mind it anymore. I think the wider wheels and tires helps there, along with the 19" rims.


It'll certainly be an interesting to see what I get when I'm done...

 

[Mountain]

I was also running on the limiter.... A LOT this past season. I'm assuming you have a 5.0L car with the MT-82 (I can't see some of your post since I'm at work). I was running the 3.73 final drive as well. I thought about going to just a 3.55. But having driven a similar car to mine with 3.55's and also doing the math on speed and RPM... I figured if I'm going to swap gears to do it and be done with it. So, I went 3.31. I couldn't be happier. Yeah, that initial acceleration from 1st is not the same, but it doesn't seem significantly different. But the car is so much more enjoyable to drive on and off track. The transmission gears are all so much more useful; everything is much less busy. Plus 3.31's will allow you to run some of the shorter performance tires.

I would only do 3.55's if you are really set on the cars current performance and just need something like 200 more RPM until the limiter. By the way, the factory "limiter" is a pain in the ass to deal with when hitting. I'm running the FRRP tune and it changed to factory limiter from power de-rate to the engine just bouncing off the Rev limit. The tune also seems to allow the engine Rev a tad higher, but maybe that's my imagination because I haven't actually logged that.

 

[dontlifttoshift]

Autocross is going to be the best venue for testing that. This is why I'm going to put coilovers on the car sometime in October: I have an Evolution driving school in November, and it'll be the perfect venue for testing the changes I've made.

I wouldn't do that. Leave the car alone and spend every second you are at EvoSchool working on your driving. Figure out what your cold tire pressures are, set them and forget it. You really want to get every last ounce out of this driving school that you can. Worrying about your new setup will not allow you to do that.

You can test your setup at a local autocross for way less money and have way more time to analyze what's working or not.

 

[modernbeat]

...Autocross is going to be the best venue for testing that...

Autocross is not the best testing venue. It relies very heavily on quick transitioning and NOT ultimate cornering grip. There are things that we do to cars that will help them in autocross, but hurt them on track. Needless to say, we only do those things on dedicated autocross cars.

Neil Robert's book, Think Fast!, was recommended to you. I recommend it also. It's one the top three books I recommend to people that want to understand how to improve the performance handling of their car. There are a LOT of other books out there on handling, but most do not address the production style cars we compete in, are outdated, or just give you a vocabulary without any real concept of what is happening. And just for completeness, the other two books are Paul Haney's excellent "The Racing & High-Performance Tire", and the difficult to read "Vehicle Dynamics and Damping" by Jan Zuijdijk.

Start with Neil's book. It's easy to read and you will likely learn something from every page. I like it so much, I actually stock it so I can turn competitors to it and they can educate themselves about making good decisions about modifications.

Think Fast: The Racer's Why-To Guide For Winning [B1-PRTF-01]

 

[kcbrown]

Autocross is not the best testing venue. It relies very heavily on quick transitioning and NOT ultimate cornering grip. There are things that we do to cars that will help them in autocross, but hurt them on track. Needless to say, we only do those things on dedicated autocross cars.

Of course, it depends on the autocross course. The ones they used at the Evolution school worked nicely, as they included combinations of fast transition sections and hard cornering sections (e.g., a 270 degree sweeper).

The track isn't the best place for testing for me because I'm not willing to push the car so hard as to risk losing control of it. Period. As such, I'm not reaching quite the same limits that I am on an autocross course.

That's why the evolution driving school wound up generating about the same amount of wear on the front tires in about an hour's worth of autocross driving time that I generated in a minimum of three hours worth of track time.


No, for me, the autocross environment (in particular, the Evolution school) is a far better venue for testing the handling of the car at its limits. Maximum grip isn't what I'm after here. The most appealing balance between controllability and ride quality is what I'm after. I'm in this for fun, not for setting lap times. It's one reason you'll never see me on slicks -- there's no point.

Once I've figured out how the car behaves at the limits, I'm a little more willing to approach them on the track, but that is clearly after the testing we're talking about has been done.

Neil Robert's book, Think Fast!, was recommended to you. I recommend it also. It's one the top three books I recommend to people that want to understand how to improve the performance handling of their car. There are a LOT of other books out there on handling, but most do not address the production style cars we compete in, are outdated, or just give you a vocabulary without any real concept of what is happening. And just for completeness, the other two books are Paul Haney's excellent "The Racing & High-Performance Tire", and the difficult to read "Vehicle Dynamics and Damping" by Jan Zuijdijk.

Start with Neil's book. It's easy to read and you will likely learn something from every page. I like it so much, I actually stock it so I can turn competitors to it and they can educate themselves about making good decisions about modifications.

Think Fast: The Racer's Why-To Guide For Winning [B1-PRTF-01]

Oh, cool! You guys stock that book? I'll be placing an order for one. I want the extended hubcaps for my Forgestars anyway, since the ones that shipped with them don't fit over the front dust caps. This'll give me even more excuse to place an order.

 

[kcbrown]

I wouldn't do that. Leave the car alone and spend every second you are at EvoSchool working on your driving. Figure out what your cold tire pressures are, set them and forget it. You really want to get every last ounce out of this driving school that you can. Worrying about your new setup will not allow you to do that.

I've already been to a couple of days worth of Evo School. I'm going to be working on both my driving and learning how the car behaves at the next one. I'd agree with you completely if this were the first one I'd been to, but it won't be. Now that I know what I'm getting into, I know what opportunities I'll have to test the car's behavior and can integrate learning the driving into that.

You can test your setup at a local autocross for way less money and have way more time to analyze what's working or not.

Well, no, I can't. At Evo school, you get something like 40 runs during the day. The autocrosses I've seen get you maybe five, because the demand for them is so high. Five runs is just enough for me to get a handle on the layout of the course, and most certainly isn't anything like enough for me to really get a feel for how the car's behaving. Evo school reduced the demands of learning the course some because the changes they made to the course during the day preserved the bulk of the course, so it wasn't like going into a completely new course from scratch.

 

[claudermilk]

I was also running on the limiter.... A LOT this past season. I'm assuming you have a 5.0L car with the MT-82 (I can't see some of your post since I'm at work). I was running the 3.73 final drive as well. I thought about going to just a 3.55. But having driven a similar car to mine with 3.55's and also doing the math on speed and RPM... I figured if I'm going to swap gears to do it and be done with it. So, I went 3.31. I couldn't be happier. Yeah, that initial acceleration from 1st is not the same, but it doesn't seem significantly different. But the car is so much more enjoyable to drive on and off track. The transmission gears are all so much more useful; everything is much less busy. Plus 3.31's will allow you to run some of the shorter performance tires.

I would only do 3.55's if you are really set on the cars current performance and just need something like 200 more RPM until the limiter. By the way, the factory "limiter" is a pain in the ass to deal with when hitting. I'm running the FRRP tune and it changed to factory limiter from power de-rate to the engine just bouncing off the Rev limit. The tune also seems to allow the engine Rev a tad higher, but maybe that's my imagination because I haven't actually logged that.

Yes, a 5.0 with MT-82 and 3.73 rear. I hate how the rev limiter works--the car just falls on its face. I'm learning by ear when I'm getting close & starting to breathe the throttle a bit--it's either that or negotiate a 2-3-2 shift (which means I really need to get the Whiteline bushing installed and MGW ordered.

I really like hearing that the Ford Racing tune changes the limiter that way. I am jealous listening to the Evos & Hondas able to just bounce off it. Are you running the ProCal (M-9603-MGTB) or TrackCal (M-14204-MGTTC) tune? I'm looking at the latter.

I've already been to a couple of days worth of Evo School. I'm going to be working on both my driving and learning how the car behaves at the next one. I'd agree with you completely if this were the first one I'd been to, but it won't be. Now that I know what I'm getting into, I know what opportunities I'll have to test the car's behavior and can integrate learning the driving into that.

Well, no, I can't. At Evo school, you get something like 40 runs during the day. The autocrosses I've seen get you maybe five, because the demand for them is so high. Five runs is just enough for me to get a handle on the layout of the course, and most certainly isn't anything like enough for me to really get a feel for how the car's behaving. Evo school reduced the demands of learning the course some because the changes they made to the course during the day preserved the bulk of the course, so it wasn't like going into a completely new course from scratch.

Are you on their Phase 2, Challenge, or Dial-In schools then? Is there a practice event prior to the regular autocross events by you? CalClub always runs a Saturday practice event the day before the regular championship event on Sunday (and I really need to go to one).

 

[dontlifttoshift]

The pro cal tune bounces off the limiter, it's kind of fun.

 

[kcbrown]

Yes, a 5.0 with MT-82 and 3.73 rear. I hate how the rev limiter works--the car just falls on its face. I'm learning by ear when I'm getting close & starting to breathe the throttle a bit--it's either that or negotiate a 2-3-2 shift (which means I really need to get the Whiteline bushing installed and MGW ordered.

I really like hearing that the Ford Racing tune changes the limiter that way. I am jealous listening to the Evos & Hondas able to just bounce off it. Are you running the ProCal (M-9603-MGTB) or TrackCal (M-14204-MGTTC) tune? I'm looking at the latter.

Unfortunately, the TrackCal tune keeps the stock limiter behavior. I'm not terribly happy about it, but I've trained my ears to tell me when I'm there, so I tend not to hit it all that often anymore.

Are you on their Phase 2, Challenge, or Dial-In schools then? Is there a practice event prior to the regular autocross events by you? CalClub always runs a Saturday practice event the day before the regular championship event on Sunday (and I really need to go to one).

Phase 1 and Phase 2 are the ones I've been to and have signed up for again. Their formats are the same in terms of the number of runs available.

I've not investigated the practice events, but since the number of runs is determined by the number of participants, why would you get substantially (an order of magnitude) more runs there than at the main event?

To put it in perspective, Evo school limits the school to around 20 participants.