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Old 02-21-2013, 04:19 PM
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Steve, Let me know if you make a decision on this. I may not be able to make the april event, but I would like to go to roebling sometime soon.

M2cupcar, I would love to pick your brain about this stuff sometime in person.
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Old 02-21-2013, 08:45 PM
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Old 02-22-2013, 08:58 AM
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warning- lots of blathering below

You have the right attitude to go faster- knowing you're not. As long as you know that the car has never gone as fast as it possibly can around the track, you'll always seek to improve.

I watched the vid, and yes, generally it looks normal- throttle on, lines, apexes etc. And agreed- you have no idea how hard he was really trying. I think what's key is for the instructor to give the student a feel for what that car can do, what the sensations are "up there." That video is nowhere near that IMO. But that's "his" choice. Once you are driving the car to maximize vehicle dynamics, you then increase the potential of the car. Make sense? Of course that's not as easy to do in a weekend vs. regular instruction. And then you're face with instructor's own limits. When I was starting out, I found an instructor that was good and willing to bring up the pace with me riding along, so I sought him out. Even after I was promoted to solo I would seek out other drivers/instructors that I thought could offer something.

Originally Posted by Scrappy Jack
...but it seems like a big gap from ~1:31 to even 1:27, let alone sub 1:25.
This is true. With quickness and consistency comes the appreciation for smaller gains. There is a every steepening curve to those record lap times, and as I mentioned before, they're not attainable without the right combination of skill and equipment. This also brings to light the advantage of data to demonstrate consistency. You need to know that you've actually made a half second gain by improving something, rather than losing a second by your change, and fixing five other mistakes you didn't know you were making. I think it's a frustration a lot of drivers don't know exists.

I'll cite the example I mentioned above. I was convinced that my speed through T3 at rd. Atlanta was so great that there was no need to downshift to 3rd. Though looking at the data showed me with a 3mph advantage in turn 3 over my student. But because he was downshifting to 3rd gear he was actually out "dragging" me through the long sweeper (no-name) and 1mph quicker than me into the esses. Doh!

In a single sentence of advice- keep the car as-is, seat time, and stay honest.
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Old 02-22-2013, 09:17 AM
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Originally Posted by Scrappy Jack
My car was corner-weighted and aligned prior to the event that I'm using times from. Unfortunately, the message board I had my "build thread" on got vaporized so I have to go back and check my hard copy notes to verify the actual alignment settings.

I've got video of his laps and mine, but no data overlay and there was no legitimate timing equipment in the car at the time.
Code:
          Left      Right
Caster
   Front   4.32*    4.37*
Camber
   Front  -2.02*   -2.00*
   Rear   -1.81*   -1.78*
Toe
   Front   0.02"    0.00"
   Rear    0.00"    0.01"
Corner weights (with 158 lb driver) were:
Code:
       Left      Right
Front  648 lbs    603 lbs
Rear   605 lbs    553 lbs
Total  2409 with driver, 2251 without
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Old 02-22-2013, 09:26 AM
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Thanks, Rob. You posted while I was compiling that masterpiece of a chart above.

My current plan of action is:
  • Run some basic diagnostics to make sure the car is not down on power due to a mechanical issue (e.g. low compression, exhaust leak I am not aware of, etc).
  • Use the Pbox for data acquisition and analysis.
  • Try to have my instructor drive at least one portion of a session in my car.
  • Get my towing situation sorted out so I can get more seat time, seat time, seat time.

I have already mentally prepared myself to not be in a rush to go solo and I do appreciate that there is a wide variety of skill and pace in the instructor group.
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Old 02-22-2013, 09:29 AM
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I'm pretty sure I'm going at this point.

That track looks incredibly easy on brakes, but I'm debating needing to add some camber back in for it. I took some out for squaring up the contact patches in the braking and accel zones at Sebring. I was using up the tires in the braking sections by burning off the inside edges of the tires long before the outsides were worn. My ride height is a bit high because I only have 550/350 spring rates in an overweight car (and Sebring is rough), so I was getting a fair amount of camber gain as the wheels traveled upward. I wasn't using the outside shoulders of the tires much at all.

What do you think?
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Old 02-22-2013, 10:42 AM
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Rob, Thats essentially what im trying to do. I want to keep the car as much the same now for as long as I can. That being said, I did just order a 14mm rear bar to try and take a lot of my understeer out of the car. From the sounds of it, you seem to be recommending getting a daqs such as a trackmate or so? Worth the cost, or just stick to seat time for now?

Six, If I can afford it, I would like to come by as well, but I rather doubt that will be happening. Ill let you know if things change though.
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Old 02-22-2013, 11:01 AM
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Originally Posted by Gryff
Rob, Thats essentially what im trying to do. I want to keep the car as much the same now for as long as I can. That being said, I did just order a 14mm rear bar to try and take a lot of my understeer out of the car.
Where else have you run the car to determine it has too much understeer? I will defer to the more experienced, but I might be inclined to run with your current setup first and then switch to the 14mm rear bar after putting in some laps at RRR.

From the sounds of it, you seem to be recommending getting a daqs such as a trackmate or so? Worth the cost, or just stick to seat time for now?
A lot of the guys at the events I've been to have used the premium Harry's LapTimer with their super smarty phones. It has lap timing + video overlay. I think it's only ~$20 plus a solid windshield mount. If it had been around when I bought my Pbox, I might have just gone with that.
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Old 02-22-2013, 12:03 PM
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Road Atlanta, and Cmp. I would love to have someone else more experienced than I drive the car and see what they think. but the problem is I have my seat bolted to the floor, it fits me 5'7" 150lb and not much more than that.

Harrys lap timer is always an option as well, I would just need a window mount for my phone to pull that off.

Edit: I can certainly play with the rear sway, before putting the 14 mm on the car.

Last edited by Gryff; 02-22-2013 at 12:37 PM.
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Old 02-22-2013, 12:49 PM
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Originally Posted by Gryff
Harrys lap timer is always an option as well, I would just need a window mount for my phone to pull that off.
Apparently, TomTom used to sell an enhanced GPS phone mount setup that was pretty good but I can't seem to find any for sale new. They may be discontinued.
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Old 02-22-2013, 01:04 PM
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Yeah, but thats the least of my worries right now, I want to get this car handling a little better, and seat time more so than anything.
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Old 02-22-2013, 01:15 PM
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If I had the option for daqs in the beginning and knew just how valuable it was, I would've spent the dough. I only have experience with traqmate, but know there are way more options. Even the most fundamental system should work to some degree. And the data is always there to review- either between sessions, that night or between events. That combined with in-car video should be a huge help for learning.

The advantage to a driver ed is that you're not competing, so keeping the car as a constant will allow you to isolate the driver. Believe me, I understand the pain in not tinkering- I autocrossed stock class for three years, and then raced showroom stock for three years. But that forced me to only consider the driver and mechanical wear as cause for less speed. Plus anything you do spend on parts won't go to seat time.

I raced a Miata for three years that was setup for somebody shorter than 5'7" and I'm 6'. It was only uncomfortable until the race started. Good training to put things out of your mind that matter. I just drove with my knees bent up and made adjustments with feet for pedal control. And for the record the car had a good cage with the knee bar up at the firewall deep behind the dash.

Scrap- your car looks set up well for tracking to me. But like I said, if you put 200# in the pax seat everything changes.
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Old 02-22-2013, 01:18 PM
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Buy something like this: Universal GPS Car Mount Holder for Garmin Nuvi 255 260 260W 200 255W 265W | eBay

Buy a molded plastic belt clip for your phone. Cut off the clips on the GPS mount and cut off the belt clip. Epoxy them together and you have your phone mount.

I made one for my old phone for ~$15.
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Old 02-22-2013, 01:26 PM
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Originally Posted by m2cupcar
If I had the option for daqs in the beginning and knew just how valuable it was, I would've spent the dough. I only have experience with traqmate, but know there are way more options. Even the most fundamental system should work to some degree. And the data is always there to review- either between sessions, that night or between events. That combined with in-car video should be a huge help for learning.

The advantage to a driver ed is that you're not competing, so keeping the car as a constant will allow you to isolate the driver. Believe me, I understand the pain in not tinkering- I autocrossed stock class for three years, and then raced showroom stock for three years. But that forced me to only consider the driver and mechanical wear as cause for less speed. Plus anything you do spend on parts won't go to seat time.

I raced a Miata for three years that was setup for somebody shorter than 5'7" and I'm 6'. It was only uncomfortable until the race started. Good training to put things out of your mind that matter. I just drove with my knees bent up and made adjustments with feet for pedal control. And for the record the car had a good cage with the knee bar up at the firewall deep behind the dash.

Scrap- your car looks set up well for tracking to me. But like I said, if you put 200# in the pax seat everything changes.
Want to drive my car sometime soon then? see what you think?
I do feel like some sort of daq is invaluable, I hope to get something in that department soon.
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Old 02-25-2013, 08:25 AM
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Unfortunately I'm not so well connected to all the clubs for instructing anymore. I am going to this AMP event though. Not sure if there are spots at this point.
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Old 10-21-2013, 10:56 AM
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Originally Posted by Scrappy Jack
So what sort of laptimes are people running at Roebling?

I am trying to figure out if my car is horrifically slow or if it's actually in-line with reasonable expectations. With an experienced instructor and SM racer, the car ran in the 1:31s. I was a few seconds off that pace.
Just got home from my third event at Roebling Road Raceway. I was pretty consistently in the 1:31s with clean laps. My best of the weekend was a 1:30.5.

I made three changes:
  • Sticker BFG Rivals (225/45-15 on used 9" TRM C3 wheels) vs the heat-cycled Kumho XS (205/50-15 on 8" 6ULs)
  • Full TSE Big Boy Pants Brake Kit with DTC-60 pads (with M-Tuned Sport rears and ducting)
  • I drove much better lines

I'll get some video uploaded at some point. I will once again say that having the instructor in the car has been a big help. I have been getting lucky with my instructors and this last one really helped me push to find more time.

Because the car is so slow, the brakes are insane. I need to review the video, but I think I am braking at the 300' mark into turn 1, maybe 250, then I don't touch the brakes again until into turn 4. I am overslowing most of the time into 4 so there is time there.

Turn 5 is deceptively difficult to get right consistently. Turn 7 requires obscene amounts of patience and I am leaving some time on the table there as I build confidence to go flat-out sooner with the throttle steer.

I am killing some of the slower drivers out of 8 and 9 when I get the line through 7 right.

Attached Thumbnails Roebling & Brakes-roebling.jpg  

Last edited by Scrappy Jack; 10-21-2013 at 04:34 PM. Reason: Fixed BFG Rival size
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Old 10-21-2013, 12:38 PM
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Whoa, hold up... where'd you get 245 Rivals?
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Old 10-21-2013, 04:34 PM
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Originally Posted by Dunning Kruger Affect
Whoa, hold up... where'd you get 245 Rivals?
Sorry; fixed that. They are the standard 225/45-15 Rival size.
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Old 10-21-2013, 06:06 PM
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NM

Last edited by hornetball; 10-21-2013 at 06:39 PM.
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Old 10-23-2013, 08:04 AM
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I should probably start a thread for my car, but in the meantime, some photos from Roebling, courtesy of AWOL Photography:







Attached Thumbnails Roebling & Brakes-awo_3053-2852387265-o_zps7c8d2e15.jpg   Roebling & Brakes-awo_9307-2852378231-o_zps20a9b9e0.jpg   Roebling & Brakes-awo_3907-2852374922-o_zps17d5b905.jpg   Roebling & Brakes-awo_9141-2852376102-o_zpsd4e1d448.jpg  
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