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Old 10-10-2021, 04:32 PM   #400
IROCZman15
10 Second Club / Meet Coordinator
 
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Join Date: Dec 2004
Location: Roxbury, NJ
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Went to Island Dragway on Friday night for Test and Tune, along with Jerry who was running his 57 Chevy. We had a good time; early on the track needed to come around a bit, but after that, things went pretty well. Glad to have helpful advice from Jerry with all his wisdom, thank you dude! Before arriving at the track, I stopped to visit with Larry and Chris at 2nd Gen Engineering and we chatted for a bit as well. Good times!


Front struts are non-adjustable 90/10 Lakewood's and the rear Koni shocks I set at 3/5 drivers side and I tried 4/5 on the passenger side. Front tires were at 48 psi all night and the rear tires were between 18.0 and 18.4 psi all night long. Still suffering from the nervous jitters with the nitrous and even sometimes forgetting to hold the damn button down during the whole pass. That I hope to change, and hopefully soon! The moisture content was high all night, humidity in the 89%-91% according to my app. The DA was about 1200 at the start of the night and right about 1,000 at my last run, again according to my app, which is less reputable than most.
-on all nitrous passes I had the nitrous set to come on at 3,000 rpms. I might lower this to come on directly when I do launch because its almost feeling like I have a "double launch" sensation.
- I use the same timing numbers for my 100 and 125 nitrous shots, so I actually use the same tune file. so even though it says F125 on the page, I use that same file for a fixed 100 shot.. same goes for the progressive shots. I am pulling 4.5 degrees of timing for both a 125 and 100 shot. So it is at 29.5 deg on nitrous, and 34 deg on motor.






Pass 1:
All motor, no nitrous. Did a very short burnout because I forgot to pump the brakes hard before activating the line lock, so about 1 second into the burnout it pushed through the brakes and darted me forward. The track starter motioned that I could do another one (and I should have) but I told him no and staged. Foot brake launch at 1475 rpms and it instantly spun. Pedaled it, short shifted 1-2 at 5400 rpms, and then short shifted 2-3 shift at 5,421 rpms, crossed the line at 6177 rpms like a total goofball and it ran 12.23 at 113. The top green line is my Throttle position sensor, so you can see I was not at full throttle most of 1st gear and all of 2nd gear.

Timeslip:



Datalog:



Video:
https://www.youtube.com/watch?v=U560xdwQQiU





Pass 2:
Hoping to redeem myself from the above nonsense, I decided to do a progressive-ramp 100 shot. After a proper 7 second burnout, I footbraked the launch at 1580 rpms and then the ramp came in at 3,000 rpms. The 1.52 sixty foot felt real good! The green line in the datalog thats across the middle of the page, you can see the timing ramp before it goes flat. When it is flat I am on the nitrous, when the line goes upwards and then flat and then downwards, those are moments I am off the nitrous. As you cans ee I was off the nitrous between the 1-2 shift, the 2-3 shift and again (twice) at the top of third gear. Anyways, I shifted 1-2 at 6,700 rpms, 2-3 at 6,230 rpms, and crossed the finish line at 6515 (of the nitrous). Same as last TnT event, I am out of rpms at the top of 3rd gear (more info on that later), but thats why you hear the engine "lay over" about 200 feet from the finish line.

Timeslip:



Datalog:


Video:
https://www.youtube.com/watch?v=GxxjR17KXVo



Pass 3:
Changed from a progressive 100 shot to a fixed 100 shot. Did a 6 second burnout and footbraked the launch from 2,002 rpms. Shifted 1-2 at 6,706 rpms, 2-3 at 6,417 rpms, and across the line at 6,536 rpms. Again, not on the nitrous with 200 feet left before the finish line.. out of rpms. I was on the button the whole time and the only time the nitrous turned off is when it hit the "high rpm limit" at the top of 1st gear and also at the top of 3rd gear. I did notice (and can be seen in the log also) that I had less footage between where I was and the finish line when the nitrous went off at the top of third. food for thought!

Timeslip:



Datalog:



Video:
https://www.youtube.com/watch?v=KqhbmUODOMQ




Pass 4:
I decided I was ready to change from a 100 shot to a 125 shot, so I did. Did a 7 second burnout and footbrake launched from 1693 rpms. Shifted 1-2 at 6,782 and 2-3 at 6486 rpms which put me crossing the line at 6477 rpms. I know the nitrous clicked off at the top of first gear, and it appears that I got off the button while shifting from 2-3..and didn't get back on the button for over 2 seconds.. .until I was mid way through 3rd gear! ugh, you can hear it in the video too.


Timeslip:



Datalog:




Video:
https://www.youtube.com/watch?v=vf0lhM3OumI



continued below...
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Last edited by IROCZman15; 10-10-2021 at 06:42 PM.
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