Two weeks ago I drove the car to Island for a Sunday daytime test-and-tune.* I wanted some more action on the 27" tall Hoosiers (BiasPly, no rim screws) so when I got to the track they were bolted on and the MT drag radials I drove there on were removed. I had a few pounds less than a full nitrous bottle when I arrived, and I was intending to work on the car's all-motor 60 foot and timeslip and then later a few nitrous passes but knowingly shutting it off early (the 27" tires put me wayyy too far into the rev limiter before the finish line on the nitrous).
Pass 1:*
All motor pass, Hoosiers set to 16.6 psi on each side, Rear Koni yellow shocks set to a soft 1.5 each. Forgot to fully empty rear air-bags, whoops! Footbrake launch at 2201 rpms, flashed to 4803, shifted 1-2 at 6238 and 2-3 at 6318, crossing finish line at 6181 rpms.*
Timeslip:
Datalog:
Track Photo of my actual first pass:
Video:
https://www.youtube.com/watch?v=UqtVn5baWt4
See-ya mustang video:
https://www.youtube.com/watch?v=jx_Qf7Y0WMk
Pass 2:*
Emptied rear air-bags to near zero. Tires had heated up to be at 16.8 psi each so I left them there, no changes to shocks yet. Footbrake launch from basically idle at 956 rpms, flashed to 4686 , shifted 1-2 at 5978, shifted 2-3 6209 and the*finish line at 6218 rpms.*
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=-3hRBC4bP-g
Pass 3:*
Increased rear tire pressure to 17.4 psi each. My buddy John convinced me to make a fee "open loop" fueling runs so I did these next two passes with closed-loop comp turned off. Footbrake launch at 1851 rpms. Flashed to 4816, shifted 1-2 at 6374, 2-3 shift at 6216, and across the finish line at 6222. The AFR gauge on the holley dash and the newly remedied AEM afr gauge both displayed mid-12 afr readings by eyesight the whole pass and the run felt good overall. Actual*numbers can be seen in datalog and also the gopro video.* However, It is still not launching as expected with these tires, and the advice I soon finally paid attention to, is the rear LCA bar angle needs to be adjusted to take a more level angle for a bias-ply tire. I considered jumping under the car and changing a bolt hole, but I got carried away with other stuff and decided just to lower the rear shocks to a very soft setting for the next pass:
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=f0AyZPKMPt0
Pass 4:*Shocks were then lowered to a very soft 1.0 each, tires had heated up to be 17.8 psi so I left them there. I did another open loop pass because I liked what I had just seen on the datalog for pass 3. However, I double-clicked the button and did not get a saved datalog for this run. It was simple and smooth run, but still not in the 11.50's as I had hoped for.*
Timeslip:
Video:
https://www.youtube.com/watch?v=P8Y8iwLiJ80
Pass 5:
Done with the all motor passes. Was not thrilled about the slower-than-usual sixty foot times but hoped I could have success with the Hoosiers and some nitrous, maybe a quick sixty foot launch and run the car out to the 1000 foot mark a few times.*Launched at 1182 rpms, flashed the converter to 5001, shifted 1-2 too high at 6438 while off the button, shifted 2-3 again too high at 6432off the throttle and button, back into 3rd gear, then chopped the throttle and drove the rest of the pass*on-motor.*
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=IRxLZdiYkso
Pass 6:
*I was a bit happier*with the 1.43 sixty foot, but knowing this car has been in the 1.3's before, I wanted more out of it so I got right back in the lanes and hot lapped it; no changes to anything. Footbrake launch from 1966 rpms, it spun a bit and flashed up to 5154 and climbed to 6575 rpms when I got off the button and throttle to shift, back on it in 2nd, shifted into 3rd at 6235 rpms, climbed into mid 3rd gear while still on the nitrous, but got off the button and rode out the pass all motor finishing at 5577 rpms.*
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=pMBFzM4k9l8
Pass 7 :Knowing I would need to make a LCA change to get the Hoosiers to probably work better (but not wanting to do it and then un-do it very shortly in order to drive home on the*radials) I decided to just put the MT drag radials back on for the rest of the day. The track also had made the announcement that they will be closing at 3:00 instead of 4pm, so I only had time for a few more passes. Set the radials at 19.6* psi. Kept the rear shocks at the low setting of 1.* Footbrake launch at 2143 rpms, spun real bad, pedaled it, shifted 1-2 at 6419 rpms, 2-3 at 5909 and held the nitrous until 6083 rpms and chopped the throttle off exactly at the 1000 foot cone, dead-coasted the rest of the way to the finish line.*
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=keTrLPXpYKg
Pass 8:*Getting greedy and got right back into the lanes and made this pass just minutes later.* Sat at the light for a few seconds and Footbrake launch at 2193 rpms, flashed to 5055, shifted 1-2 at 6306, shifted 2-3 at 6234, hit torque converter lockup button at 6025* and then got off the nitrous before crossing the finish line at 6202 rpms.*
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=UMbz73XofX0
Pass 9:
Lowered the rear shocks down to 0.5 settings on each side, Rear MT radials set to 19.8 psi. Footbrake launch at 1962 rpms, and the converter flashed to 5232. shifted 1-2 at 6443, shifted 2-3 at 6305 and while watching the nitrous bottle pressure gauge drop steadily during the run, I climbed through 3rd gear while finishing at 6244 rpms. You can see me point to the N20 bottle pressure gauge after the run, it got down to just below 800psi on that pass so the bottle was now no longer useable.*
Timeslip:
Datalog:
Video:
https://www.youtube.com/watch?v=SWYDmTMuSB4
Drove the car home without any issues. Of note, the DA was in the 1800-2300 range all day and the car stayed hotter than usual all day long. Not worried about that. Speedometer is fubar again, as can be seen during the GoPro video footage on the dash. Will re-do the whole assembly this winter.
I have some adjustments to do before the next track day, which will be the October 24 Track Rental at Island Dragway.