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Discussion Starter #1
I took mine to the local SCCA AutoX this weekend. There was one other STi there.

His ambient temp was 80 track temp 90. Mine was 95/120. There was a definate loss of power and grip as the track heated up.

His best tire pressure was 45 front 42 rear hot.
Mine was 47 front 41 rear hot.

I could feel plenty of tire roll and slip. After the second run the tires were too hot to maintain proper grip for me. I was able to drop .4 seconds on each of the first 3 runs. On the last run I had lowered the tire pressure too far and gained .7 back.

Driving impressions:

If rolled easy into a corner or a mid-corner lift there was a ton of understeer. Even with left foot braking it did not want to turn.
On the other hand if you pounded on the brakes and tossed the car into the corner and hammered the gas you could easily with steering inputs go from neutral to tail first slide.
This course had a large increasing slalom that went from 5,000 rpm in second at entry to 6,000 rpm in third at exit. The car was very easy to transfer side to side.
The most fun was a line of cones that constitued a hairpin. This was entered at revlimited 2nd with hard brakes to 1st. (No problems going to first at speed) Then apply parking brake while accelerating to rotate 180 then release to complete four wheel power slide. The DDCD unhooking with the parking brake really works.
I only used the DCCD in auto. With only 4 runs and working with tire pressures I did not have time to experiment with manual settings.

Left foot braking and heel-toe operations were all fairly easy. I did not have much movement in the seat. I used factory belts. I move the seat back one click pop the belt to engage the tensioner and then move the seat back up to make sure that it stays tight.

All in all a fun blast. The web site is not up yet with all of the times for the event.
 

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WOW!! :D Great info. Thanks for the time to document your experiences.
 

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330hp 2.0L STi

XB9R - My impressions and experiences with 2 autox'es in the Sti are exact with yours. The only difference would be tire pressures. We were running 40F, 44R.

One thing that I have noticed though: On course designs that allow higher speeds (2nd/3rd Gear), the Sti will push through sweepers and descreasing radius turns.

I am going to play with the DCCD settings for next time. Based on what I've been reading, it looks like for tight autox'ing, set the DCCD to manual with the dial pulled all the way back (Farthest from Lock, essentially running the center diff open). For open, higher speed courses, two clicks up from there. Will try and report back!

Launch Note: Set DCCD Auto, leaving the roller in the desired two clicks up or full open setting. After hitting second gear, hit the DCCD button to put it into Manual mode! Atleast that's the plan. I will probably only succeed in turning on the windshield wipers, hitting the horn, and Coning the finish ....And still be in DCCD Auto. :lol:

(edited for grammar)
 

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lol, I will try to mess around with some DCCD settings this weekend at a school I am instructing at. I am running Kumho ECSTA R compounds, so the pressures and car handling is a bit different. I ran two runs on the stock tires and the car was very difficult to drive on the autoX course. The Kumho's are much more predictable and do not push as much in the tight turns.
 

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Agreed. Once you put the Kumhos on, it will be like starting over. I will be in the same boat by next week or so.

This is probably the funnest car I've ever autox'ed.
 

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Hey Xman I have been hearing that the ECSTAs wear a lot faster than the VRs. Do you any experience with both of these models? Thanks.
 

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I haven't used the V700's before, but the ECSTA's do seem to wear pretty quickly initially. I have almost all the tread grooves worn off and I HOPE the wear will decellerate. I think they will last me the whole season without a problem (as long as I don't spin too often)

Maybe next year I can afford Hoosiers
 

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Discussion Starter #8
I will agree that 3rd gear sweepers the car will push. The course I ran had a sweeper that was 6,000 in 3rd that finished into a tighter turn that exited into a braking straight to a low rpm 2nd gear corner. You had to feather the brakes to make the car turn. I think in the future I will use the ebrake to slow and rotate the car in this type of turn.

I do not know about different tires. Each tire will have its own particular charateristic on the car.

shaqnwrx- why did you have less pressure in the front? Were you trying to get the car to rotate?
 

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Ran my first autocross in the STI.

I tried the 44f 40r, but found a ton of understeer, with DCCD fully back, e.g, rear basis.

Used the Auto setting in wet and actually went faster (same tire pressures)

Maybe I was trying to over do the power in the dry runs, but I would be tempted to put more pressure in rears. (BE070)
 

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it really sounds like you were overdriving the tires. I ran the Bridgestones yesterday and found the 44f 40r to be fine when I got the car really slowed down in the corners. These RE070's like to slide in the slaloms and sweeping type turns but don't like hard constant radiuses. They put the power down nicely and are not a bad tire but take a lot of patience to slow the car down more than you would like to before entering the turns.
 

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We had an auto-x this past weekend with the BMWCCA. The course was a 50-60 second course with two skidpads and short straights laid out in a very complicated manner, but was very fun. there were two STis, one Evo, and many BMWs.

I set the tires to 38/38 and I had no roll-over at all, but I am not sure I pushed as hard as I could, this was my first auto-x in the STi. The other STi driver (a veteran autocrosser, but first time with the STi as well) and I set the DCCD to full back after trying "auto", the handling was nicely balanced with a tad understeer. In the uneven skidpads, in the long sweeping turns we did not get much push-out, but modulated the throttle frequently. This really did help in bringing the back out slightly. The tires howled incredably as if someone was attacking them with a knife, but held-on.

My best time was mid-pack with a 55.8, and the other STi driver's best was 52.2. He missed FTD to a heavily modified '88 M535 which ran 51.8. One thing for sure, however, pushing the STi was a lot of fun, especially pulling out of corners and rocketing to the next one.

The Evo driver's best time was 58.x, but it was his very first auto-x. Later in the day, another experienced driver drove the Evo to a 53.9 for his best time, but that was his first time in an Evo.

Overall, BMWers were impressed with the little Jap compacts :)
 

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:D Just want to thank you guys.

After my inital post I gave 44f and 40r another try (2nd Auto X with STI). It worked fantasically. I beat the fastest Evo by over 2 secs (on a 50 second course, I was the only STI :( ). Although I think the Evos should have been a closer in time.

Also set the DCCD, 2 points from fully back, excellent balance on a "Fast" Auto X course.
 

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Guys, I know you all ran lower pressure in the back.. but from the 2 autoX I'v done with mine.. I had better success with 41F 41R, DCCD one click from full open.
This tire pressure\DCCD combination is really confusing the hell out of me. Can anyone give me some more info?
 

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Mister2cool said:
Guys, I know you all ran lower pressure in the back.. but from the 2 autoX I'v done with mine.. I had better success with 41F 41R, DCCD one click from full open.
This tire pressure\DCCD combination is really confusing the hell out of me. Can anyone give me some more info?
Our Notes
 

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Dyno sheets

Good notes! I agree with the handling stuff -- at the autocross you have to keep remembering that if you go in too hot, you've blown the corner, as you'll push forever coming out, which means you can't get your power down -- thereby losing your one huge advantage. At the road courses the turns aren't so tight, so it doesn't happen as much (or at least isn't as painfully obvious).

Also, one thing I've noticed with mine is that if you aren't careful, you can get the springs all loaded on one side, then if you try to do quick flick, the car will start to turn, followed a couple seconds later by all that weight just flinging itself over all at once. Be ready for it! Or better yet, be on the ball, looking ahead, giving smooth inputs... I believe SGP addresses this in their chassis/suspension notes. Does anyone know what the stock spring rates are?

Regarding steering, I started with a stock 1996 Miata, went to the STi, and after a few autocrosses I did another one with the old Miata. Wow -- talk about differences in steering (and everything else). The STi requires a lot more steering input for the same direction change. The Miata is so much better. No power at all, but great steering and great shifter. Of course the STi is easily 2 seconds faster on a 40 second course (Azenis on the Miata, RE070s on the STi). But much more brutish about getting there, and other than the acceleration, doesn't amke me smile so much during the run.

You think the brakes are that bad? I changed the fluid to Motul 600 RBF before my first track event, and have not had any problems with the stock pads. Admittedly I am not a fast driver, but using the stock pads in 13 separate 1/2 hour sessions with no fade seems to imply they're not that bad. Now for autocross, they are not my favorite at all. You must get on the brakes with a smooth initial input, or it will "skate" along as the ABS goes into fits. I've heard from someone with an RX-7 that this is very unusual and his car doesn't do this at all -- he just slams his foot down full-bore to do the best stops. With the STi at the auto-x I've had the opposite -- a sudden stomp on the brakes means horrible braking.

Once again, I have to agree with the SGP reactions about the DCCD. I've tried different settings, and auto has always been faster. Sure, manual at two steps up from open feels better coming out of corners, but the times are always slower for me. This has been true at both the dry events and the one damp one.


Oh yeah -- had my first autocross with a little rain. Huge fun! It was just barely sprinkling -- about enough to want the wipers run about once every 3 minutes. Unfortunately, after our run group, the second group ended up with no rain for their last runs, and their last 2 of 6 were basically dry (experienced people were turning times 2 seconds faster than their previous times on their 5th run). Still, how many times will you see a first-year autocrosser in a stock car with stock tires hold FTD for the whole first run (yes, I beat the A-mod and B-mod cars!). Their second run saw them get a handle on the traction and blow me out of the water, but it was still cool. I ended up 6/63 in PAX on the dry day and 5/55 on the wet day (with 3 of the people above me getting their time on the dry runs -- the other one just drove the snot out of his SM car, which turned out to be a bit much as the axle broke on the last run).
 

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Speed Monkee Performance 0 loss grounding kit

WRX_Mundi,

These are interesting comments and notes. I certainly will be replying, but we are getting ready for an auto-x tomorrow and I will not have time until Sunday.

I thought, I should not leave it in the air hanging... ;)

Thanks.
 

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WRX_Mundi said:
...
Also, one thing I've noticed with mine is that if you aren't careful, you can get the springs all loaded on one side, then if you try to do quick flick, the car will start to turn, followed a couple seconds later by all that weight just flinging itself over all at once. Be ready for it! Or better yet, be on the ball, looking ahead, giving smooth inputs... I believe SGP addresses this in their chassis/suspension notes. Does anyone know what the stock spring rates are?
Your assessment is spot on. The responsiveness of the STi is one of the points that has room for improvement. The delay you experience is quite natural in many vehicles, but can be improved with more aggressively valved shocks and polyutherane bushings, or also with some driving style adjustments. For this reason, during slaloms in an auto-x, you really have to start turning when the nose of the car is about 1-2 feet prior to the cone you have to actually take. One technique that I am still trying to learn to do better is to pre-load the weight transfer with a quick but minor steering input in the direction of the upcoming turn, may be about a second before, and turn when it is time. That way, you do not suprise the car, but give early warning that the turn is coming and move the weight first to the center and then shift it towards the outside. It is somewhat difficult to time it, but experienced drivers do it flawlessly. A great example of this technique can be seen in old videos of Senna driving, it is just amazing.

WRX_Mundi said:
Regarding steering, I started with a stock 1996 Miata, went to the STi, and after a few autocrosses I did another one with the old Miata. Wow -- talk about differences in steering (and everything else). The STi requires a lot more steering input for the same direction change. The Miata is so much better. No power at all, but great steering and great shifter. Of course the STi is easily 2 seconds faster on a 40 second course (Azenis on the Miata, RE070s on the STi). But much more brutish about getting there, and other than the acceleration, doesn't amke me smile so much during the run.
There is no question that the Miata is a very nimble vehicle. Low to the ground, and very light; compared to the STi. Again, you comparison is accurate.

WRX_Mundi said:
You think the brakes are that bad? I changed the fluid to Motul 600 RBF before my first track event, and have not had any problems with the stock pads. Admittedly I am not a fast driver, but using the stock pads in 13 separate 1/2 hour sessions with no fade seems to imply they're not that bad. Now for autocross, they are not my favorite at all. You must get on the brakes with a smooth initial input, or it will "skate" along as the ABS goes into fits. I've heard from someone with an RX-7 that this is very unusual and his car doesn't do this at all -- he just slams his foot down full-bore to do the best stops. With the STi at the auto-x I've had the opposite -- a sudden stomp on the brakes means horrible braking.
The braking power on the STi is tremendous, in fact, I think the tires cannot keep up with the brakes and that is why the ABS comes in so early. The STi surely needs R-compounds in auto-x and track to get to the limit. However, the pads build up heat extremely fast and does not dissipate it fast enough; that is the issue we are having. As an example, on the exact same circuit we ran our BMW 330Ci and STi (at different times). The 330 had Porterfield R4S pads, which are primarily for street and auto-x and the STi had stock ones. The 330 is about 250 to 300 lbs heavier than the STi. Granted the Sti achieved higher speeds, but no more than 10-15 mph more at the end of the straights as they were short ones (also the 330 handles better and could take corners nearly at the same speed as the STi). But the STi pads started smoking nearly 20 min. in to the session, where as the R4S pads, inspite of a heavier car, lasted all day without any sign of problems at all, and we still have the same pads on the Bimmer after 4 months :). Both vehicles had Castrol SRF, which has higher wet boiling point that Motul. I also would like to mention that the air temp during the 330Ci run average 90-95 and during the STi run, it was roughly 70-75 degrees. Take my word for it, change pads if you will do any track event :)

The Brembo pads in the STi are no where close to Porterfield R4S pads in my opinion. We will be trying both the R4 and R4S pads on the STi at VIR in December, we'll see how they go in that very fast track.

We will complete our notes during mid-December, and hopefully we will add more valuable information.

Thank you for the positive comments.
 

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[...]The delay you experience is quite natural in many vehicles, but can be improved with more aggressively valved shocks and polyutherane bushings, or also with some driving style adjustments.
I'm thinking of putting some Moton struts on together with some stiffer springs. I'm still waiting on the details, but theoretically this should be better, as long as it is set up properly.

For this reason, during slaloms in an auto-x, you really have to start turning when the nose of the car is about 1-2 feet prior to the cone you have to actually take.
At least. That was hard for me to get at first, especially in higher speed (50+ mph) slaloms. I think it's true of every car. Watching the veterans doing a fast slalom is fascinating, as it always looks like they're going to hit the cones, but the car just barely misses them.

One technique that I am still trying to learn to do better is to pre-load the weight transfer with a quick but minor steering input in the direction of the upcoming turn, may be about a second before, and turn when it is time.
Interesting. I've been trying to cure myself of little unconcious inputs during a turn and get a single smooth input. Once I get to that point, I'll try working on preloading!

[...BMW 330Ci with Porterfield R4S brake pads better than stock STi...] Both vehicles had Castrol SRF, which has higher wet boiling point that Motul. I also would like to mention that the air temp during the 330Ci run average 90-95 and during the STi run, it was roughly 70-75 degrees. Take my word for it, change pads if you will do any track event :)
Perhaps it was the street tires on my car, or just not going fast enough -- I haven't had problems with mine at the track. I agree that SRF is going to compare favorably with Motul, so that isn't it. I've been looking into the Carbotech pads as possibilities (Bobcat for street/autocross, XP1109 for track) -- any opinions on those? I'll be interested in hearing the results of your stock, R4, and R4S tests, since the R4S was also on my list for consideration.

Back to autocross, here is a video of my car at the last autocross of the season. It was damp out, which was a lot of fun, though you can see one bit of unexpected oversteer. I ended up 5th in PAX and 9th fastest in raw time (out of 55 total), which is quite good for me, especially given a stock STi with stock street tires (all the faster cars were on DOT-R or AM/BM slicks). I would have been higher if it hadn't stopped raining for the second run group, but regardless this is my best result all year. Let's hope the STi stays in ESP...

http://www.jacobsensation.com/dana/Autox_2003_11_09_run3.wmv
 

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So, I just purchased Stratmosphere's STi Cover...

The video is very nice :) I should have one soon, but it will be lower quality taken manually by a passenger.

Three things I noticed, please take as constructive critisizm:
1- at the end of the first slalom you were too fast and had to brake to take the right-hand sweeper. I speculate but I thik that was actually due to late turn-in on the very first slalom cone. I could not tell exactly, but you did not seem to be looking ahead in thatsweeper turn and that might be the reason as well. That right-hand sweeper caught you somewhat by suprise.
2- during the few right/left sweepers, it looked (not quite visible however from camera position) you had quite a bit of room left towards the cones. Inches count as you know :)
3- The last slalom, again, you turned in to the first cone too late, as we were discussing in previous messages.

However, I thought you were quite smooth, big advantage, and the way you handle the steering seems very natural and controlled; great job.

As for the Motons... I do not have first-hand experience. They are very well known for sure. However, about 2-3 months ago, the Grassroots magazine had a shock review, and they came in last; actually posting worst times to OEM shocks. All shocks in the test (Koni, TC Kline Koni, Moton, EOM) were tuned properly after installation. However, they think Moton shipped them incorrectly valved ones and that is why they did not post favorable times. The purpose of the test was to determine if agressively valved shocks alone could improve run times, and the conclusion was a definitive "yes". I honestly cannot tell more.

However, as you can imagine, since we sell JIC and TEIN coilovers; I am biased towards them. Also, we sell those because we like those brands and also DMS (which will start carrying within a month or so). There are so many brands out there, and they are all quite good that it is impossible to keep up with all their little nuances. But may be in a year or so we might start carrying Konis and even Motons if we become comfortable with their products that we can actually recommend specific applications to customers :)

If you do end up getting the Motons, I would certainly would love to hear more about your expriences during the 2004 season. Sincerely!

A lot of people like and use Carbotech pads. Somehow, I just could not warm up to them. I like Porterfield pads and Hawk Performance. Btw, I checked our notes and the 330Ci that particular day actually had OEM brake fluid as apparently we had run out of SRF.

On the STi, we will go with the R4S pads for VIR testing in December as the weather will be cold any way. If they fail, we'll switch to R4 pads, and if they do not; for me it would mean that the R4 pads will perform even better. So, I do not think, unless forced to, we will be testing R4 pads specifically. We already extended our testing budget for this year :)

Great conversation, thank you for the contributions :) keep them coming.
 
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