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Old 08-16-2013, 01:29 PM   #1
Fair
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Hanchey has two decades of experience, as does Casey and Stuart, and they were all 2 seconds off the pace even after a few laps. That's not a knock on their driving - no, its showing that this mess of a set-up is that hard to get used to. I've co-driven with Weiss and Hanchey many times over the past 20+ years, and they can usually hop into any car and go fast as Hell within 1-2 laps. But when proven, fast drivers like these hop in the car, and it still takes a significant learning curve. Luckily we've already been "learning" this for months. Given another dozen laps they would have been right on pace. Even after 5+ autocross events in the car and dozens of laps, its still difficult. Costas was literally making throttle changes with his toes thru thin racing shoes - not the typical ankle movements - its that sensitive.


Left: Costas during one of our many tire changes for the day. Right: Hanchey working with some F Stock racers on ASTs in a 2007 Shelby

They all felt that because of the very abrupt power application the car was nearly undrivable, and certainly holding us back. Hanchey was convinced the car had serious throttle tip-in/mapping errors. This was a 30 second test course run entirely in 2nd gear, nowhere near redline but always in the meat of the powerband on every corner or transition exit. Hanchey said to "try a run in 3rd gear" to prove his point. I told him that was crazy, but we humored him. Costas made 3 laps in third gear. It was ~2000-2500 rpm lower than in 2nd gear at every spot on course. He came in and said "No way, that felt SLOW", but it was .3 sec faster - best run of the day so far. WTF?! Yes, there is a problem with power application and this proved it.

Now it wasn't faster on every lap. He took 3 laps like that to get used to it, and the first lap was slower, the second lap was even, and the last was a bit quicker then all previous laps. It was the change in power application, but also a *large* change in lines he took through the cones. Very different line could be utilized with the less sensitive throttle. More of a "momentum" line than a point and shoot line. But in the end, it was faster cutting back on the power by running the higher gear through the course.

Why is that? Let's explain - modern fly-by-wire throttle systems have the ability to tweak the throttle response (correlation between % pedal opening and % throttle body opening) by both the OEMs and tuners. The "trick" is to make the throttle mapping much more "falling rate" or digressive, which make the cars "feel faster". This means - the first small percentage of pedal opening makes for a LARGE percentage of throttle opening. So when you barely give the car a little gas pedal, its opening the throttle very aggressively, and it FEELS FAST. Which makes it very difficult to delicately adjust throttle, which is all you do in an autocross with a powerful car. That's been the case all along with this car, both with the stock tune and the aftermarket tune we added via the SCT Tuner. This is actually the 2nd throttle mapping we've tested and its still MUCH too aggressive.

Throttle Mapping Issue = Found!

What we actually need, to make the car easier to control at lower speed events like autocrosses, is a rising rate throttle map as described and charted on page 36 of Neil Robert's excellent "Think FAST" book. And I quote, "A rising rate throttle... provides fine control over the lower power end of the throttle range. That helps you blend cornering into forward acceleration smoothly and early". An example of this from the 1960s was the uber-powerful and light Can Am cars, another quote, "Jim Hall said that a rising rate throttle linkage was an absolute must on the big block Chevy (1000+ hp) Chevy-engined Chaparral Can Am cars to make them anywhere close to being drivable." We don't have a 1000 hp big block underhood but we are trying to take 400 whp V8 and power it through somewhat narrow street tires, and do so in a parking lot, in lower gears, with abrupt power transitions.



So the throttle mapping is a big thing that needs to be changed, and throughout the day I kept asking Costas to make a run or two in 3rd gear, every hour or so. And every single time, on every set of tires, and every permutation of shocks, the car was as fast or faster in 3rd, a higher than optimal gear, because it was so much more drivable. Matching those times in 2nd gear took extreme control and wasn't nearly as repeatable. The shop that is providing our custom SCT tunes for the Mustang was called and we described the issue in great detail; we were already on a supposedly less aggressive throttle map, but now a third custom tune was created, and Paul M and I just loaded it to the Mustang this evening. We'll be testing this in anger this coming weekend at a SW Texas Divisional series 2-day event.



The next big revelation was in shock revalving. We had already had AST-USA revalve the fronts but the rears were still pretty much "off the shelf". Hanchey had a suggestion, we asked them to try the valving change he thought would help, they revalved the shocks on the spot, and it made a huge difference in times right off. It has us thinking about some even more radical shock ideas to test in the near future- which, for business reasons, I'm going to test before we explain these plans.

After this significant jump in times was from the shocks verified on several more laps with the Yokohamas we moved on to the Toyo R1Rs, then the Dunlops, each time re-verifying the shock settings front and back as well as the tire pressures that worked best on the Yokes. So which tire won? Well, it was pretty close between two of them, and I don't want to spill everything just yet (need time to crunch numbers and edit video), but the Toyos are for sale...


Fresh set of 265/35/18 Toyo R1Rs ..... now FOR SALE!

These R1R tires are still full of tread and have less than 20 total autocross runs on them, all in the last 6 weeks. Still very fresh, great durometer numbers, so how about $600 + shipping? Probably make great track tires for somebody (and I will keep them for just that if I only get low-ball offers). They won't be going back on this Mustang for STX use, that's for sure. We do really like the Dunlops, even these 3 year old former street tires we tested with. I bet you will see a fresh set on our car soon, for testing head to head with the Hankooks and Yokohamas, and possibly in some unusual sizes. We learned some things that day that we want to verify with even more testing.

We didn't have time to run into town and have the Hankooks mounted - the 265/35/18 Hankook RS3. So we've already mounted those and they will be run this weekend at the SW Divisional here at TMS. But as the day was winding down we did re-mount the first set of ours - our control set, the Yokohamas. We noticed only a slight uptick against the original times, so the temperature creep didn't account for more than .1 sec of our overall gains, from beginning of day to end.



OK, so what did we learn? How much time did we gain, if any? From the beginning of the day, starting with shock and tire pressure settings we'd refined so far this season, to the end of the day, we found 1.1 seconds on a 30 second course. That's.... a lot. This was between testing some unusual tire pressures, the various tire testing, and most of all the shock changes (valving changes uncovered almost a second alone - you can't tell me "shocks don't matter much"). And this is still with 2nd gear power application almost impossible, and the car quicker in 3rd gear. Will this latest round of improvements + a new throttle map translate to a more competitive car on a full SCCA sized course? We hope so.



THere's a couple of stills from the "tire cam" videos (that I still need to edit/upload) showing sidewall deflection; the Toyo was compared to the Dunlop & Yokohama. Costas also managed to replicate that unusual "limp mode" error icon on the dash that I ran into event last month. It happened 3 times during the day, but he wasn't allowing any more wheelspin than normal, just the same massive amount we always see in 2nd gear. He'd notice an abrupt lack of power, abort the run and come in to show the icon; I snapped a picture of it. To clear the error you have to turn the key off and restart the car. Odd.

More soon,
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Old 08-16-2013, 01:29 PM   #2
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Project Update for May 18, 2011: There was a 2-day SCCA Divisional autocross last weekend here in Ft. Worth (Texas Motor Speedway asphalt bus lot) and I just got finished with the video edits and picture uploads. I haven't had time to do the "tire cam" videos or DL-1 data maps from the tire test from the last update - sorry! But we did so some more "tire testing" this weekend, by running the 265/35/18 Hankook RS3 tires in the event. And in case you haven't heard the latest news - AST bought Moton!



Since Costas had a work thing come up this weekend he was out, so it was Amy running in the Women's PAXed class (instead of a bunch of 1-car Ladies classes the women in our region have put together a combined PAXed class similar to ProSolo's L1/L2) and me running in STX. We walked the course and it was BIG and had LONG straights, which should suit the higher powered Mustang in STX. Armed with a perfect course (thanks, JJ!) and what we learned at the Riverside Test-n-tune 2 weeks ago (new shock valving, perfected settings and tire pressures, lighter set-up with 2 race seats) I was feeling better about our chances this weekend. Well, other than the fact that neither Amy nor I made a single lap at the Test-n-tune due to her not being there and my fractured rib. So... hopefully my notes and talking with Costas about his "revised driving style" from that event would help? And we had a new throttle map from Steeda that we loaded this week, so it should be "easier to control" the rear tires this time. Right?


In-car videos from Amy's Day 1 runs; left is run 1, right is run 4

Yea... not so much. Amy ran first and she said wheelspin was horrible. The new throttle map was just as aggressive. Ridiculous. Needless to say I'm looking for a local SCT-capable tuner that can work with us on this. So Amy went into "crutch mode" and made the rest of her laps almost entirely in 3rd gear. She dropped 3 seconds just by sticking it into 3nd gear on her 2nd run. Its sad, but this cuts power down yet lets the car still accelerate well enough. You then have to modify your line and "momentum drive" it like a Miata. Well, a 70" wide Miata. She was also battling with COLD track and tire temps also, with ambient only in the high 40s but 20+ mph winds that kept us all shivering. She knocked some time down and had a .25 sec lead over W (mostly STX cars) at the end of her first day's 4 runs.



I ran in the next heat, where it warmed up a touch. I had bumped my injured rib up against a fence while taking pictures of Amy during her runs, so I now had serious, bone-deep pain - and no pain killers with me. I could barely breath while belted into the race seat, and was frustrated with the jacked up throttle map, leading to some pretty impressive looking (driftoro!) but otherwise slow paced runs for me. Excuses: I've got plenty!


That sideways crap is deep into 3rd gear. The course workers were RUNNING for their lives, but I never hit a cone all weekend

So it was back to the same old power oversteer antics, lots of 2nd gear rev limiter, refusing to upshift when the tires were spinning, trying all sorts of stupid lines, pushing my braking zones too far, choppy lines, not driving smooth - nothing worked, and I was in massive pain the whole time. Long story short, after my 4 runs I was 1.3 sec back from Ledbetter's STX E36 328is, buried in 6th place out of 8. And as poorly as I drove, I wasn't surprised.


In-car video from Terry's Day 1 runs. Left is run 1 (sideways), right is run 4 (not much better)

more...
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Old 08-16-2013, 01:30 PM   #3
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continued from above

Day 2 started off a lot better for both of us. It was the same course, run backwards, but it drove smoother/flowed better this way for some reason. The big decreasing radius right hand straight/turn became an increasing radius left hand straight/turn, which allowed for a lot more traction and speed in this RWD car. I had also watched our Day 1 runs on video and saw where Amy was going too slow/too smooth and where I was too aggressive/driving too deep into corners. Our straight speeds looked 15-20 mph different!

I asked her to push it more on corner exits and try to use a little more 2nd gear (and do a lot of up/downshifts), while I toned down my corner exits dramatically, also making as many as four 4 upshifts/downshifts per run. Any place where I had wheelspin I would upshift to 3rd, then go back down to 2nd into the next turn. Kept the feet busy, but it worked. Amy had some runs where she kept using 3rd on much of the course but was all much more aggressive. Our modified driving style on Day 2 paid off - with zero set-up changes we were both faster relative to our classes/field on this day.


In-car video from Terry's Day 2 runs. Left is run 1 (quick out of the box), right is run 4 (.3 sec faster)

After her 4 runs Amy was .75 sec ahead of the next closest W class entrant after both days, looked significantly faster, and was only .7 slower than me for Day 2 (again running on a colder part of the day). I had a quick first run (51.3, almost Ledbetter to within .003), which was still more or less still 2nd fastest after my 4th run improved slightly (51.0), again almost exactly tied with Ledbetter for Day 2 and only .2 sec behind his co-driver. That felt good, and if the event had been a one day thing and Ledbetter didn't have his 4th run, I would have almost called this a victory.



So Ledbetter was already the winner for the weekend by the time he came to the line for his 4th run, and then he busted off a pressure-free time that was a solid .7 sec faster than me for the day. Damn.... you gotta kick a brother while he's feeling good?! Heheh... Nice job Chris! He's a Vorshlag VTPP tester and has been on fire this year.


As you can see, on day 2 I was still a bit "exuberant" with the throttle...

So after 2 days of runs I was 1.9 sec off the pace at our little Divisional. Not good, but Day 2 felt a lot better after I had some time to adapt to the new suspension set-up and driving style. Toning down my asshat driving antics made the biggest difference; masking the throttle issues by upshifting also helped, but doesn't fix the root cause. I think I still need more seat time to get used to the set-up, and to further smooth my inputs, and we all still need a rising rate throttle to be able to control the wheel spin issues. So instead of dropping $1900 (on fuel/hotel/entry fees/food) and missing 2 days of work we are not going to attend the double-header Pro & Tour in Lincoln, NE over Memorial Day weekend in 2 weeks. That sucks, but we just are not "in the hunt" right now and can better expend our time & resources at another test day (where we can get 70+ runs, not 4, and try more set-up changes) and then follow up with more local and Divisional head-to-head competition before we start traveling to more "big autocross events".



We also still have a LOT of areas on the car untouched - just scratched the surface. And since the car is no longer held back by NASA TT class limits, we're going to explore them all. We've already got more parts in hand to test with this week - things which directly should help with rear traction. There are still 100 pounds left to remove legally, if not more. And I've got leads on some SCT tuner shops that are local to us (Dallas) that I'll go see about this whacked out throttle map.

How about the Hankooks? We also need to verify the performance of the 265/35/18 Hankook RS3s vs 265/40/18 Yokohama AD08s (control tire) vs 265/35/18 Dunlops vs "another set we're going to be testing", at another test day soon. Lots of runs, figure out the best tires, then play with the IR tire array and get the ideal camber and pressures. Once we finalize the tires (too many choices!) we can start hacking away at the other many variables. After 16 runs on them between the 2 of us we like the Hankooks so far, and they seem to make good grip, but "they didn't feel as consistent or turn-in like the Yokohamas" (quoting Amy). She's won big on Yokohamas, and I guess have done my best on them as well (a 2nd at Nats), but we're going to reform our opinions based on lots of back-to-back testing on the current generation tires and try to ignore the internet chatter and our own past experiences.

We're also still shooting to get to 450 whp in STX, and somehow we've going to get it to the pavement. Stay tuned - we're not giving up!
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Old 08-16-2013, 01:31 PM   #4
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Mini-update May 20, 2011: Pictures DO say a thousands words. A buddy of ours (STX competitor and VTPP tester Brad Maxcy) took some great shots of the Mustang at the Divisional last weekend. He has an awesome camera/lens and is also not a total photo hack like me.



These close-ups show that the car looks pretty composed in most corners, well, at least when Amy is driving (when I'm behind the wheel its nothing but jackassery). Loaded up laterally like this it looks to be cornering pretty flat, outside front wheel still shows negative camber, and the inside front is just barely staying on the ground.



The outside rear wheel is definitely going into positive camber under load. We need to see what we can do about that. Could be all of the sloppy rubber bushings in the rear suspension all loading up....

More soon,
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Old 08-16-2013, 01:32 PM   #5
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Project Update for June 2, 2011: We dropped the Mustang off at True Street Motorsports in McKinney, TX today and they fixed all manner of things + diagnosed some other quirks we've run across. I finally found a good tuner shop (just 6 miles north of our location) that can custom dyno tune the 2011 GT via the SCT tuner we have, and they already have a great reputation. The owner of the shop also owns a 2011 Mustang 5.0 GT, which they've modded and tuned already.

Their tuning guru Sean Burt (who, as luck would have it, tuned our 7.0L Alpha car's new motor when it made 488 whp, back at LG Motorsports in 2009) started out by getting a baseline dyno run in the car with the existing custom tune + the Steeda cold air installed, which was 389 whp right at 5000 miles on the odometer. This compares to the initial dead-stock dyno pull (on the same style DynoJet 224) of 367 whp at 500 miles on the odometer (uncorrected it was 378 whp - it was a cold day) on Nov 18, 2010 (see bone stock dyno chart below).


This was the corrected bone stock dyno number at 500 miles back in Nov 2010 (uncorrected print-out is here)

I explained to Sean in painful detail what I wanted: more control, not necessarily more power. Probably one of their only customers asking for a custom tune but not wanting more peak power. I talked about tip-in throttle, falling rate vs rising rate throttle response, and the massive power-modulation issues we were having in 1st and 2nd gear, on corner exit in autocross events. I asked him to drive the car to see if he can feel the difference, before, during and after his tweaks.

After talking to some other local 2011 Mustang GT owners I was also curious why the car feels like it has a 200 pound flywheel. I made some calls earlier this week and according to the folks at Fidanza the OEM flywheel is only 21.5 lbs. They were the only place I called that had an answer - because they make a lighter 2011 GT aluminum flywheel (12 lbs) and had weighed the stock unit. We cannot use an aftermarket flywheel in STX, but I just wanted to know what the stock unit weighed to see if it would explain the sluggish nature of engine revving - it didn't.

This afternoon when I went to pick up the car Sean had a lot of great information for us, as well as two new tunes loaded to our SCT unit and three color print outs of the various dyno pulls. That seems trivial but when you pay for dyno tuning you sometimes have to ask for printouts. They even videoed the dyno pull. Great service! They are also familiar with HP Tuners and other software packages, and I noticed several LSx powered cars as well as an SRT Challenger in their shop for tuning that day.

They tinkered with our Mustang off and on for several hours, made some calls to some other SCT gurus, even to some folks at Ford. Here's what they relayed to me:

1. There is a very weird steering feedback issue we had noticed but didn't mention to him, as we thought it was just a bad wheel bearing (we already received a new pair to install, next). He brought this up after driving the car... the explanation he had was bizarre, but it makes perfect sense. Its possibly a programming issue (that he cannot alter), so once we test this theory to verify his conclusions I will post up about it. Don't want to spread bad information if this isn't the cause. Its something we've been noticing for a while, but had not mentioned here yet.

2. The "heavy flywheel effect" is all in ignition timing. The OEM tune adds 66 degrees of ignition advance in "engine deceleration mode" (off throttle, falling RPMs), which slows the engine responsiveness. He changed this to a normal 12 degrees and wow, what a difference. The engine response is SO much more lively! Its easier to rev match downshifts, too. I had no idea that could be in the programming.

3. Sean says they've used 7700-7800 rpm redlines in these new Coyote 5.0 engines without issue. Yikes! The dyno pulls show that the motor is starting to lose power above 6700 rpm, so it doesn't make sense to go to these stratospheric revs unless its in an autocross situation where we're barely touching those high revs, to avoid a 2-3-2 shift on a short straight. Anything we can do to avoid a lot of shifting is a win, especially after the last autocross (where I needed 4 separate 2-3-2 shifts per run!). We'll keep an eye on the harmonic balancer (check for slipping) and oil usage, but we've gone ahead and moved the redline on our car to 7700 rpm, up from our previous 7400 number, and way up from the stock 6800 redline. Zing! I'm already looking at aftermarket SFI rated balancers, for long term durability.

4. So last, but not least - the throttle mapping. Again, everything is all new on 2011s, as they can tune 2005-2010 throttle mapping easily. Sean tried to alter the correlation of pedal to throttle like I asked for, but there are something like 3 separate data tables/variables necessary to drive this interface, and he said if he altered all 3 the computer would "throw a wrench" error code on the dash. He says he has tried this on 2011s and it keeps "relearning around the tuning". He did try something very novel on our "track tune" and it might be effective - more than just running the car in a higher gear (our autocross testing showed Costas to be faster in 3rd gear rather than running in 2nd - which was such a kludge of a fix we'll try anything). Again, this tuning trick might be a flop so we're going to hold off on explaining about what he did until I can prove that it works. We will be testing the new tune at two autocross events this weekend. He loaded another identical tune without this throttle tricking tweak as our "street tune", which I can switch to in 90 seconds if the other doesn't work out. This "street tune" in fact makes more power... but again, we cannot use the power we're making in autocross situations, so this unusual "track tune" might indeed be faster.


Today's final 2 tunes with a peak number of 392 whp, corrected

So where are we now? 4500 miles later with one single bolt on part (cold air) and a custom tune we're at 392 whp, up +25 whp and +28 wtq on the new "street tune" over stock. That's pretty damn good power for an STX legal car with an air filter and "some 1s and 0s". A tiny part of the increase in peak numbers is the rise in the redline, as the bone stock dyno pull was just barely still going up at the stock 6800 rpm fuel cut. But the shape of both the new power and torque curves look nearly identical to stock, with the numbers up across the board, and the new power peak is only at 6700 rpm. So the cold air + the tune = a win.

Talked to an exhaust supplier yesterday and I'm anxious to get their full length 1-7/8" header set-up coming. Picking that larger header primary diameter to help kill some more low end power while giving a little more on top - unless the new tune is magic, in which case I'll go with their 1-3/4" primaries. Until now, adding any power anywhere would just make the car slower in autocross, so if this new "track tune" allows us to modulate throttle and corner exit faster then we can finally go ahead and look at more power, which is there for the taking. Then we can focus the rest of the season on more suspension bits.

Next up! Two autocrosses this weekend, including Saturday's National Street Tire Challenge and Sunday's Texas Region SCCA Autocross #3, both being held at the massive Mineral Wells complex. Amy and I are driving the Mustang in 2 different classes at each event, and we might even be running on different tire packages as well. We do have a strange, new wheel and tire package we're testing this weekend, which is funny looking and sure to draw some laughs, but it might help cure some of our power issues. If it doesn't work, I won't mention it in my next post, photoshop them out of the pics, and deny we tried it if asked.

More soon,
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Old 08-16-2013, 01:32 PM   #6
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Project Update for June 13, 2011: We had two autocross events on the weekend of June 4-5, where we tested the new engine tuning (throttle mapping) and some new wheels/tires, with the first real promising results for the car in STX class to date. Let's start with the new rear rubber first, then cover the two very different autocross events separately.

17" Rear Wheels and Tires

After the very positive results we had with some very worn and borrowed 18" Dunlops at our Tire Test in April, we wanted to try some fresh 265 Dunlops. We thought about just plopping down for another set of 265/35/18s but instead we tried something different...



Dunlop has the only ST legal/competitive tire that is a 265mm max width for STX in a 17" diameter. This might be one of the only STX cars that can physically fit these 265/40/17 Dunlops under OEM fenders, too. (I've seen these used on an STX classed E36 or two, but those cars had massive compromises in ride height to clear these uber-wide tires) I'd love to run 17" diameter wheels and tires on the Mustang at all 4 corners, but the Mustang's (optional) front 14" rotors and Brembo calipers don't allow this. Up front. But on the rear...



Hell yes! The rear brakes are small enough to allow a 17" wheel to clear, so we bought a pair of wheels and got some 265/40/17 Dunlops mounted to them. The wheels are lighter (TireRack calls them "15.9 lbs") but the mounted 17" wheel and tire (45.0 lbs) is 3 lbs lighter than the 18x9" Enkei FP01 and 265/40/18 Yokohama (48.2 lbs) but is 2 lbs heavier than the 18x9" WedsSport and 265/35/18 Toyos (43.1 lbs). The Toyo R1Rs are way too soft for use on these big cars, so that lighter tire has its drawbacks. Keep in mind the OEM 19x9" wheel and 255/40/19 tire was 57 lbs, so its still 12+ pounds per corner lighter than that. The 265/40/17 Dunlop is actually .1" taller than the 265/35/18s we had been running, so we don't lose any tire height or alter gearing this way.

But we didn't go to the 17" Dunlop for "lightness" - we did it for increased sidewall height and lower cost. The dollars and cents are easy to understand: its $100 per tire cheaper to get the same exact Dunlop Star Spec in 265/40/17 vs 265/35/18. That's $400/set, and hard to ignore. But we've wasted $3K testing various tires and wheels on this car this year, so cost is pretty much thrown out.

Corner Exit Acceleration is the biggest aspect we need to improve on this car (and most autocross cars, for that matter), and we had a long way to go on the Mustang. Throttle mapping was part of it but we're looking for other ways to improve this acceleration direction. The thought that a taller sidewall could reduce some of the shock load to the rear tires crossed our minds. Going to the 17" tire allows for more sidewall height and potentially less spring rate in the tire sidewall.



There are "rules of thumb" regarding sidewall aspect ratios and in one book (ThinkFAST) race engineer Neil Roberts (Costas' close friend, and an old college racing buddy of mine as well) claims that he likes to use nothing shorter than 40 series tires. Sometimes we don't have a choice, but this time, we did. So we tried it. Looks goofy with 19" wheels on the front and 17s on back (above left), but the 18/17 combo (above right) doesn't look quite as jacked up. We've seen other autocrossers mix wheel diameters front to back, and even OEMs do it (but usually the other way around). So I had planned on running the 17's on back during the first 3-4 runs of the NSTC event and switch to the 18s for the last half. The best laid plans...

National Street Tire Challenge, Saturday June 4, 2011

Note: I've re-written this NSTC event summary several times, trying to be less negative of the course layout and the event in general. This is considerably "dialed-back" and as "PC" as I can make it. I do appreciate all of the hard work that went into putting on this event, and my main gripe is really just the uber-tight course. This is my brutally honest assessment from a 24 year veteran of SCCA autocrossing. Remember - I'm also driving in a very wide car with lots of power and limited rear grip - the proverbial bull in a China closet on a course like this - so that paints my views in a certain light. I wasn't alone in my harsh criticism of this course.

70 cars were there for Saturday's NSTC event, which was an autocross strictly for street tire equipped cars (140+ TW). Great idea for an event, as I'm a big supporter of the various ST classes and feel they are pushing racers out of dated and to some extent broken classes, like Stock and SP. For this series (4 events in 2011), run by the Milwaukee SCCA Region, they have 4-5 classes (all PAX based - my least favorite way to create a class), prizes for each class, and a free set of Bridgestone tires to the top PAX time of the event. Well.... except for any of the Street Touring Shootout class cars - they were not eligible for the PAX ranking or tires. That wasn't spelled out very well (none of the classes/rules were very clear to some) and some competitors felt a bit slighted by the way they handled that. Oh well, now we know - don't enter the PAX-combined ST class if you want to win the tires. And don't show up without an AWD car, either.

We noticed some serious issues as soon as we walked the course. The course... the course was BAD. It was not representative of anything I would call an "autocross", as it was more akin to a gymkhana course, with lots of stopping, crazy tight turns. The course drove over the dirtiest parts of the event site, with 2-3' tall grass over many sections - they needed a lawn mower on this thing. Not kidding. It "walked" so tight and un-flowing, but it drove tighter than Hell. It is hard to describe how bad this course flowed, you just had to drive it. I came to a near stop about 6-7 times on each run, there were never two corners that flowed together, every slalom cone and offset was spaced/timed differently from the one before, and the course was heavily biased to narrow cars as well as AWD cars. For having 40+ acres of asphalt to play with, and for making a 100+ second long course, to never get over 50 mph? That's just wrong. It was dubbed "The Milwaukee Beast" by the Miata drivers. Yes, the Miata guys thought it was a big, long, tight, nasty mess.



After making my morning runs I couldn't understand how our local course designer JJ could have made such an abortion of a course. I found out later that JJ had almost no say over the layout this time; the NSTC event organizers walked the course and made changes to every corner, insisting that it be super tight. A good 90% of the drivers I talked to hated the course and vowed to never to go to another NSTC event.



The throttle mapping WAS much better, but this course made everything feel bad. A go-kart would have felt big and cumbersome in this mess. It was also very hot outside, and with such a long damned course the rear tires got greasy halfway thru the run if I allowed any wheelspin at all. I was spraying the rear tires 3 times after each run, fighting for rear traction through the many tight corner exits. It felt pretty loose and disconnected on the 17" Dunlops and almost as bad on the 18" Hankooks (which I ran up front all weekend and out back after my 4th run Saturday). I did a quick pit stop tire change after run #4 of 6 Saturday, and was faster on the 18" Hankooks, but its not a fair test - this course shouldn't be used to judge anything about any car's handling. The results from the rear tire testing really have to be thrown out, this time.

more...
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Old 08-16-2013, 01:33 PM   #7
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continued from above



Many racers that day were so disgusted with the course that when they heard that Sunday's SCCA Regional event was supposed to run the same course backwards the next day, they decided to back out on their paid entries. We even had a large number not show up for their afternoon runs Saturday - they simply abandoned the event. Some of the local SCCA folks had to work extra corner assignments to cover for all of the missing folks. It was that bad. And it was damn hot - I think I saw 97°F Saturday. We lost more than a couple of folks to heat exhaustion.



There are "Class Results" and even "PAX Results" - I guess you can call them that. The classing was all PAX based, and I'm not a fan of the black magic voodoo they use to make up these PAX factors. The problem here was that its not applied evenly, as you could only use stock class or street prepared PAX factors. Also, the "ST Shootout" cars (ST, STS, STX, STR, STU) have some bogus mega-PAX handicap so they are at the bottom of the PAX results. Just... ignore the PAX results I guess.


You can hear me cursing on almost every in-car video run from that event, linked above, so of you watch the videos make sure you keep the volume down or call "earmuffs" for the kids. On a positive note, Vorshlag sponsored the beer at Saturday night's party, which was frosty and delicious. The burgers and beer were a win, as was Bidgestone's road crew bringing out their mega-trailer, tire changing equipment, and crew (below, left). I was a little embarrassed that they drove across the country to sit in this miserable heat for 3 days and have only 70 people show up. Still, Kudos for Bridgestone for sticking with us all weekend!



In an astounding bit of irony, Andy Hollis won the random drawing for a free set of Bridgestone tires at the end of the event (above, right). Ha!

And again, as negative as this write-up is, I do appreciate the hard work that went into setting this up, I thank the various sponsors, the local SCCA region people who spent 3+ days at Mineral Wells getting this set-up, etc. I'm sure someone liked the course - the fellow that won the tires surely did. Also, big thanks to Brad and Jen Maxcy for doing so much work to help set-up the SCCA's portion of this event and for taking these great pics (more at autoxmax). I barely had time to snap any pictures at all, but here they are.

Texas Region SCCA Event #3, Sunday June 5, 2011

The course designer that was unfairly blamed for the NSTC course (by me and others - sorry JJ!) announced in the afternoon Saturday that "Sunday's SCCA course will look nothing like this", and he stood by his word. With only about an hour of tweaks (and 2 hours of sweeping) Saturday night, still following the same general layout as before, the Sunday course flowed so MUCH better. The stupid tight, herky-jerky mess that was the NSTC course was completely gone. Unfortunately the Saturday event scared off many of our pre-registered Sunday racers (the entire Austin, TX contingent left, as did many other Dallas area regulars) and our attendance dropped to only 54 on Sunday. That's a shame, as it was a lot more fun running this more "normal" course and they really missed out on a fun event. But it was hotter still - we saw 103°F when we left.

Amy ran in the "W" PAXed Womens class in the morning "A" heat (3 runs in the morning, 3 in the afternoon), but with 1 other STX ladies driver there wasn't much "PAX effect" on the results. She knocked down some blisteringly fast times in her 3 attacks at the course, even with a migraine headache that started Saturday afternoon - she said her head felt like it was going to explode wearing her helmet on Sunday. The heat was a big factor in this, but she still managed to put up the 5th fastest PAX time for the event in those 3 runs and clobbered both W and the STX open class. She passed out inside the timing trailer after she made her 3rd run and didn't drive in the afternoon at all.

I ran in STX with the usual suspects - Brad Maxcy and Chris Ledbetter in their AST/Vorshlag/Hankook equipped 328is BMWs, plus Ledbetter's co-driver Sherrie. We ran the "B" group and were running very similar times to each other, trading off the lead almost every run - we finished our 3rd runs within .1 sec of each other. I was feeling better about the performance of the car, especially considering that Amy was over 1 second quicker at a 78.040 sec run. I went to her and asked what she was doing differently - in her migraine daze she said she was smooth, attacking the offsets, stepping on cone bases, and just driving well. She also managed to do the whole course in 2nd gear, where I was shifting to 3rd in the back section. I think the excessive shifting was slowing me down, so in the afternoon I left it in 2nd and tried to be smooth.



After my 4th run I was quicker by a few tenths and in the lead again, at least for a short time. Maxcy and Ledbetter got quicker on their 4th-6th runs, so I was back in my normal 3rd place by day's end - but closer than ever (.391), and Amy was still quicker then all of us, in the same car in only 3 runs, and ran the course when it was dirtier. The throttle response was markedly improved and the car was handling better than it ever has in an autocross. So I was excited with the performance of the car overall - its finally showing some promise. STX class beat STS, STR and STU that day, with Lebetter PAXing 7th, Maxcy 8th and me back in 12th.



So we left Mineral Wells Sunday night sweaty, dehydrated, in pain, and generally dead tired from being at the event site for 3 days. We weren't out there as long as some others, but it was still a bit of a whipping.

Up next: Our new autocross timing system has now arrived (big thanks to SPS!) as well as a bunch of new cones, so we have everything needed to hold our own private autocross tests now - so expect to see some more tire testing, soon. We talked to the guys at Bridgestone and they were keen on possibly getting us a set of RE11s to go head to head with the Hankooks and Dunlops. We will see. Next event: 2-day Divisional Autocross this weekend in San Antonio.

Cheers,
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