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Thunderhill 2:08 lap

Old 04-29-11, 03:50 PM
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Thunderhill 2:08 lap

Went to Thunderhill yesterday and ran a personal best of 2:08.88 on the final lap of the last advanced group session. Lots of traffic throughout the day, but was able to get a good clean lap at the end. Just wanted to share since I'm so stoked! The Hankooks Z214s are amazing! I'm confident there is still time to be had on these tires.

http://vimeo.com/23053112
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Old 04-29-11, 06:44 PM
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Nice lines jrx13!

I think you might pick up a little time if you adjust your gear selection. I'd suggest 3rd gear from T2 entry until T6 exit. Also 3rd for entry of T9 and T10 then 2nd for entry of T11. Your motor wants to sing at high revs...let it!

These are the same gear selections I use when I run Thill in my RX7, as well as the spec Miata guys.

Next time you're up there try it and let me know what you think...

Guy
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Old 05-02-11, 10:20 AM
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Thanks! I appreciate the feedback!

Up until this last track day, I used to brake and downshift to third in turn 3, stay in third gear until turn 5, then came out of turn 5 in second gear and shift in the middle of turn 5a to third gear. I also used to shift to 2nd gear coming out of turn 11. My car has 4.88 rear gear and 225/45-15s. So by using a gear calculator, 2nd gear tops out at 56mph, 3rd tops out at 82mph using 8000rpm redline. I usually don't go higher since I'm not racing yet. So I was finding I had to brake more for 11 to shift down to second. Now I brake less and just stay in 3rd.

As for turn 2 and after, it's weird, but using the predictive lap timer, I was finding I am gaining time by not going through the down shifts and up shifts! You can see the predictive lap timer working in the video. It's the left display on the Racepak G2X. The right display is mph. So for this run, I stayed in 4th all the way through until turn 5 then shifted to 3rd gear for that one. Watch the video closely and you can see the predictive lap timer showing my gains. Remember this is all based on previous runs throughout the day, which were all done with more downshifting. Interesting huh? I'm always experimenting so next time out I'll try both ways again and see if it was just a fluke.

If you guys don't have a predictive lap timer, I strongly suggest you get one!

Some data points from the logger:
Top speed = 110mph
Max lat g = 1.47 left, 1.80 right
Max accel g = .56 accel, -.93 decel/braking

Previous best lap time = 2:10.9 on Nitto NT01
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Old 05-02-11, 10:52 PM
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Nice numbers. The spec miata lap time was just set at 2:07 at the regional race a few weeks ago.

finger lock is on the money on the gearing.
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Old 06-22-11, 09:14 AM
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trying to embed new video....

don't know how...
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Old 06-22-11, 09:42 AM
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[ youtube]put link here[/youtube]

Delete the spaces between the [ and the youtube and put your link where it says to

If that doesn't work, post the link and I'll embed it for you.
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Old 06-22-11, 09:47 AM
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It's a vimeo video. I tried [vimeo]link[/vimeo] and I tried the embed code too. Maybe can't embed vimeo?




anyways here we go:

ITS NOT DONE ENCODING YET!!! HANG ON!


http://vimeo.com/25457153


Quick notes:
Last session of the day. It was hot!
First time merging data & video using program called Dashware.
The Miatas in the video both running forced induction.
The gold RX-7 pretty sure has a ported engine.
No 2:08 this day but ran a very low 2:09 for my FTD.
Car was down on power due to the heat. Coolant warning light on means over 210F.
Steering angle sensor is an actual data channel/sensor that I added.
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Old 06-22-11, 10:36 AM
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Ok it's done. Can't edit my previous post. Every forum I go on has different permissions that I'm going to have to start remembering.

http://vimeo.com/25457153

Quick notes:
Last session of the day. It was hot!
First time merging data & video using program called Dashware.
The Miatas in the video both running forced induction.
The gold RX-7 pretty sure has a ported engine.
No 2:08 this day but ran a very low 2:09 for my FTD.
Car was down on power due to the heat. Coolant warning light on means over 210F.
Steering angle sensor is an actual data channel/sensor that I added.
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Old 06-23-11, 08:15 PM
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How are you capturing the steering angle? What are you using as a sensor?
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Old 06-24-11, 09:17 AM
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Originally Posted by HotRodMex View Post
How are you capturing the steering angle? What are you using as a sensor?
Glad you asked! I made a post here quite a long time ago actually:

https://www.rx7club.com/forum/showthread.php?p=9068618

I have tps & brake on/off as well but didn't yet show those in my first dashware video.

Next goal is to try to add individual wheel speed sensors.
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Old 06-25-11, 09:28 AM
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Originally Posted by jrx13 View Post
Next goal is to try to add individual wheel speed sensors.
that might not be too bad, if you're lucky the holes for the ABS sensors are there and drilled out
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Old 06-25-11, 10:57 AM
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I'm looking for a set of the ABS rings. I posted a WTB yesterday but no responses yet. I also picked up some radio shack magnets yesterday. Just looking at different things for now. Trying to keep it cheap by using proximity sensors that I have and sourced already.
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