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STLMARSHALL
10-07-2013, 08:42 AM
On Sunday I ran the last points event of 2013. Things went very well. It was my 3rd best finish of the season and I took my class by 6 seconds. I had a very good day and Bill (2nd in XP) had a very bad day. He was having some major handling problems, which seemed strange to me considering how well he ran just a couple of weeks ago.

I tried some very different tire pressures today which finally found some balance in the car. I ran 28 in the rear which was the lowest pressure I was able to find on different forums for the NT01. I upped the front tires to 40 psi which is about 10 psi over their peak performance I have seen in the past. The idea was to overinflate the fronts to kill some grip and induce some understeer. It worked! The car was more neutral than I have ever seen it and I had a blast driving today. I could push very hard and place the car into a line at will even though it was sliding in the cold temps. Lots of tire spin, sliding, and controllable drifts....what fun! I was having so much fun that I left some time on the track....but did I mention I was having a blast?

I have been playing with the new Go Pro editor so it took some time to edit the video. Here is my best run of the day. I was recording in 720p but switched to 1080 to see if there was much difference in quality. The throttle modulation you hear is me trying to "pedal" the car to find traction as the rears were spinning a bunch. At the 40 sec mark I was hard on the limiter as I entered the slalom. The vibration you see at that point under braking is axle hop as the rears lock slightly turning into the slalom. Lots of rear brake bias yet still very controllable.

http://www.youtube.com/watch?v=5P3MJbKfHdo&feature=c4-overview&list=UUd16s9zwPBUCB8EpK7OAzJA

http://i464.photobucket.com/albums/rr2/mmarshall01/20131006_155237_zps91e99abd.jpg (http://s464.photobucket.com/user/mmarshall01/media/20131006_155237_zps91e99abd.jpg.html)



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CraigS
10-07-2013, 11:52 AM
All I see are still pics.

Mike N
10-07-2013, 12:10 PM
All I see are still pics.

I get the youtube video, not sure why you don't.

So what's your long term plan to balance the car? More front bar or higher front spring rate? Softer rear springs?

STLMARSHALL
10-07-2013, 12:25 PM
All I see are still pics.

Craig I reset the links. Should be good now. Youtube has been acting funny.

STLMARSHALL
10-07-2013, 12:31 PM
So what's your long term plan to balance the car? More front bar or higher front spring rate? Softer rear springs?

Mike I currently don't have matching compounds front to rear so it is difficult to measure the balance. With all the changes I have made it got close but was still not there. The lesson I have learned is that FFR's have no business with a square tire setup. I think the 315F / 275R is a good place to start and then it can be balanced with spring, bars, shock settings, tire pressure, etc. I will have a 315/275 setup next year and should be able to finally enjoy a fairly neutral car.

STLMARSHALL
10-07-2013, 01:59 PM
Here is lap 5. I carried more speed on the front half and had a great lap going until I turned in too early and got off line. Helps to look ahead, but not too far ahead which is what I did here. This was not a driving error but a planning error. Hardest I have hit a cone in a while and only cone I caught all day.

Also my 1st video trying the Go Pro fish eye removal:

Run 5 no fish eye - YouTube (http://www.youtube.com/watch?v=feM9cfXTJB4&feature=c4-overview&list=UUd16s9zwPBUCB8EpK7OAzJA)

Mike N
10-07-2013, 02:30 PM
Mike I currently don't have matching compounds front to rear so it is difficult to measure the balance. With all the changes I have made it got close but was still not there. The lesson I have learned is that FFR's have no business with a square tire setup. I think the 315F / 275R is a good place to start and then it can be balanced with spring, bars, shock settings, tire pressure, etc. I will have a 315/275 setup next year and should be able to finally enjoy a fairly neutral car.

I just put 315/275 NT-01's on my car and have been running them a lot closer to my street tire pressures, typically 25 back 23 front, and the car feels pretty nicely balanced. My pyrometer is on loan to another forum member at the moment so I will wait until next season before playing much with pressures. The lack of wear on the edge of the tread is indicating that lower pressures are probably warranted.

STLMARSHALL
10-07-2013, 03:32 PM
I was running 25 in the back but tried 28 on Sunday. I am not sure if that was better or not as it was very cold. Mike it is good to hear someone else is running the NT01. They wear fast but they hook up like no street tire can.

Mike N
10-07-2013, 06:34 PM
I haven't had an opportunity to run the NT-01's back to back with anything else but to me they feel pretty darn good compared the the V710's that I was running. They don't have the crazy grip that the A6 has but I wouldn't want to drive any distance on the road on the A6's. So long as it's not heavy rain the NT-01's do just fine.
22367

STLMARSHALL
10-07-2013, 08:40 PM
I haven't had an opportunity to run the NT-01's back to back with anything else but to me they feel pretty darn good compared the the V710's that I was running. They don't have the crazy grip that the A6 has but I wouldn't want to drive any distance on the road on the A6's. So long as it's not heavy rain the NT-01's do just fine.
22367

Interesting that you say they are close to the V710's. I am running new NT01's 315x17 rear and Hankook C71 275x17 front. The hankooks have close to 150 runs on them and they still have more grip than the NT01's (when run at the proper pressure). I really wish that Hankook made a 315 as they last forever.

On a side note the NT01 does really well at cold temps. My Hankooks are pretty hard when cold and my competition was on newish V710's Sunday and he kept spinning. The grip of the NT01 does not change much as they warm up.

Mike N
10-07-2013, 08:56 PM
Mike.

Without running the tires back to back there is no way to know exactly how the NT-01's compare but seat of the pants they 'feel' like the V710. Neither have the grip of an A6. I'd love to get a group together for a test n tune somewhere and rotate tires amongst the cars, that would be cool. It would be great to have a couple of the Auto-crossers here make a few runs in my car just to get some different feedback on the set up.

Owlknight360
10-08-2013, 03:17 PM
Looking good Mike!!

Is it just me or did you put some fresh paint on the car?

STLMARSHALL
10-10-2013, 07:37 PM
Looking good Mike!!

Is it just me or did you put some fresh paint on the car?

Yes I painted it last winter. The paint code is PAV.

It changes color a lot depending on the light.

http://i464.photobucket.com/albums/rr2/mmarshall01/20130721_145205_zps22947433.jpg (http://s464.photobucket.com/user/mmarshall01/media/20130721_145205_zps22947433.jpg.html)

http://i464.photobucket.com/albums/rr2/mmarshall01/20130725_190232_zps60ae5638.jpg (http://s464.photobucket.com/user/mmarshall01/media/20130725_190232_zps60ae5638.jpg.html)

http://i464.photobucket.com/albums/rr2/mmarshall01/REL_0101_zpscdf11498.jpg (http://s464.photobucket.com/user/mmarshall01/media/REL_0101_zpscdf11498.jpg.html)

Owlknight360
10-23-2013, 05:30 PM
Wow, I like it. Very interesting. In the first two pics, I'd say it was black. But the last picture it looks to be a gun metal grey color.

STLMARSHALL
10-24-2013, 08:28 AM
Wow, I like it. Very interesting. In the first two pics, I'd say it was black. But the last picture it looks to be a gun metal grey color.

Steven it is a Dark Charcoal Pearl from a 2013 Dodge minivan. I used Nason 2 stage paint and mine is not exactly the same as the Dodge color for some reason. I actually like mine better than the factory paint I tried to duplicate.
https://www.google.com/#q=pav+dark+charcoal+pearl

How is your project coming? LS in yet?

Check your PM.

http://i464.photobucket.com/albums/rr2/mmarshall01/20131019_152636_zpsf093afb5.jpg (http://s464.photobucket.com/user/mmarshall01/media/20131019_152636_zpsf093afb5.jpg.html)