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Here is Daniella’s fastest run in C class. I will post a video of my fastest run later.
[video]http://www.youtube.com/watch?v=2gDduSM-tqo[/video]
Took a while, here’s ours…
Hal: http://www.youtube.com/watch?v=yaWAHfGt9JM
Diane: http://www.youtube.com/watch?v=OewJyIu0hnwI’m slow because I’m a n00b — this was my 3rd autocross. Thanks to Paul, Eric, and Jeff who coached me Saturday. With their help I went from 57 and change first run to 6th run (and my best of day) at 53.2??.
I feel like I am leaving at least 3s on the track and posting this to solicit some suggestions to work on for June!
[video]http://www.youtube.com/watch?v=RmEVvLEmD1I[/video]
53 isn’t slow for a 3rd autocross, that’s pretty good for 225 width tires and crappy Continentals! A lot a guys getting low 50’s have much wider tires than yours, and better rubber on them and way more experience.
Since this wasn’t a horsepower course and your lines look decent, the other advice is to gas earlier and brake harder! And get better tires (and wider if possible) when yours wear out.
I would disagree on that this is not a power course, this is a common misconception. There were 5 90+ degree corners that required hard braking and hard acceleration. Those are corners for horsepower cars… High hp cars are better for course that requires them to get up and go from a low speed corner. Courses with less deceleration or acceleration and more speed maintenance are more suitable for lower power cars.
Can I design a course with more speed maintenance? Seems like most courses we get with BMW is a lot of point and shoot.
I would agree with what dacat said.
I would move the camera to another location so that you get a better idea of the cars position in relation to the apex cones. I learn a lot from watching my videos in the days following an autocross.
[quote=”mp_johnson” post=1485]I’m slow because I’m a n00b — this was my 3rd autocross. Thanks to Paul, Eric, and Jeff who coached me Saturday. With their help I went from 57 and change first run to 6th run (and my best of day) at 53.2??.
I feel like I am leaving at least 3s on the track and posting this to solicit some suggestions to work on for June!
[video]http://www.youtube.com/watch?v=RmEVvLEmD1I[/video][/quote]
Well, I still don’t fully agree with you, considering there was a lot of room in some of the 90+ turns, I wouldn’t say all of them required a point and shoot approach solely for horsepower cars. Perhaps two of them were. We’ve had plenty of past courses where horsepower was a much bigger factor than this course, with a noticeable gap between regulars depending on the course design. Perhaps Dave can comment, he’s the designer and is well aware of which course he designs are geared to light vs. horsepower.
Justin, I see your point, but I don’t think it’s as much about hp as it is about grip.
My car has 300hp (335i in B class), but its open diff meant I had to deal with power-on oversteer in the turns you are talking about.To be fair, I’m far from stock… my GTI has some mods on it for canyon carving before I decided to try autocross… Lighter wheels, Michelin Pilot Super Sport tires, H&R “small” sway bars, stiffer linear springs, a couple chassis braces, and upgraded to the Golf R/Audi S3 turbo with supporting mods and tune which dynos ~330hp.
Thanks for the feedback! I think more gas/more brakes makes a lot of sense… I wasn’t looking ahead early enough so I felt kind of tentative with how much speed I could carry and how much gas I could use.
Just because a 90+ degree turn is wide doesn’t mean there are a lot of lines to choose from. In AutoX, the fastest way around these turns will be the shortest and straightest distance, the straights following these turns are usually too short to justify a wide entry like turn 2 at Laguna seca. In these type of turns, having more horsepower makes a huge difference, a m50 at 2500 rpm isn’t going anywhere.
Bmw181, I am not sure how you get power oversteer with an open diff. The spinning wheel is pushing you to the outside of the corner. Maybe you need to control your throttle input? Are you on and off the throttle?
Certainly not always the fastest way. The fastest way around a 180 u-turn is not a straight line to the wall end. Last month’s course also had a deceptive slow 90+ corner where the best line was not the shortest. In fact, it was your video that showed me that the wider line was better. Not sure where you are going with this one.
I think your opinion of what a high horsepower course is and mine differ greatly…so be it. I happen to have a high horsepower car and remember one turn that was barely fast. How do you know if you have 168 horses yourself? Are you thinking STi’s and Evo’s with 4 wheel drive are the same as our cars here, just point, turn and go?
Justin, the inside spinning wheel is not getting enough traction, but the outside wheel has enough of it. So the outside wheel makes the tail go out.
Shortest and straightest exi…. obviously you aren’t plowing straight line thru to the wall by taking a tight turn in. You want the shortest line from the corner exit to the entrance of the next corner.
The car was dynoed at 168hp, I don’t make up my own numbers. I drive a 280hp mazdaspeed 3 powering the wrong wheels with STX level mods just like the e36, I guarantee that car would have been faster on this course.
Bmw181, open diff spins the wheel with the least traction. How are you spinning the one with traction?
I would totally believe you if you handily beat your brother with the mazdaspeed, but since you didn’t, well then it’s your opinion.
I would also totally believe you if I hadn’t walked around and talked to other folks. The high horsepower people were not happy, “man this course is fast!” or “I really got the power on” was not something I heard once. Perhaps someone else can chime in here, since this seems to be a two-side, no budging conversation.
I know you don’t make up numbers, I was just asking how do you know if this was a horsepower course when you yourself were driving on it with 168.
First of all, this is the BMW club and not the Miata club. The courses are designed with BMWs in mind, and for that reason, I will always feature at least one straight where you can stretch your legs.
BTW, what matters in autox is [u]torque[/u], not horsepower (unless your engine is [i]severely[/i] RPM-limited).
I usually run simulations to help me balance the course for handling vs. torque, but I didn’t do it this time. My intuition says that this course was reasonably balanced. I watched a few videos, and I think the best drivers were spending less than 1/3 of the time at full throttle. If you find a big disparity in time spent at full throttle between the slowest and fastest cars, then you can argue that it’s a course designed for torque. I’m pretty sure this was not the case.
Next month’s course will be all about speed control.
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