First N/A shakedown passes on new combo
12-03-2016, 04:47 PM
#1
First N/A shakedown passes on new combo Finally made it to the track today with the new combo to make some passes. The weather was low 50's and pretty nice out except for the occasional gusty wind. Drove 20 miles to the track, retorque the wheels, did a look over and safety check and ran. The QA1's were set to 4 on the front and 8 on the back. I had 47 psi in the front tires and 18 in the rears (MT drag radial 27.8"). I was datalogging to try and dial in the tune at the track and did not use the trans brake.
1st pass (idle launch)
1.569
4.489
6.971
99.119.121
10.955
122.71
2nd pass (had my tuner on the phone and he made the corrections to the VE table to get the wideband corrections under 5%---the car was pulling fuel to keep it at a target A/F ratio of 13.1)
1.573
4.497
6.975
98.38
9.150
11.008
121.06
3rd pass ( I changed the A/F table to target 12.7 instead of 13.1 at WOT--back to where I was on the first pass)
1.563
4.488
6.960
99.18
9.107
10.940
122.85
4th pass(kept the tune the same but foot braked it to 2850rpms--no real change)
1.582
4.505
6.979
99.19
9.123
10.956
122.74
5th pass(changed the target A/F table to 12.7 from 12.6 at WOT---picked up a some hp!)
1.571
4.488
6.948
100.2
9.069
10.873
124.68
6th pass (changed the A/F table from 12.6 to 12.5 at WOT---picked up some more mph)
1.584
4.513
6.974
100.23
9.095
10.899
124.74
7th pass (changed the A/F table from 12.5 to 12.4 at WOT---ran into some issues)
Went to shift from 1st to second and the car shifted then went right to 7600rpms (rev limiter). I let off and coasted the rest of the way down. I am not sure if it is a shifter cable or a trans issue but will have to trouble shoot it to see. The car drove the 20+ miles home OK and shifted fine so I need to investigate.
It was the first time since July 06 that I had this car to the track so I had a blast. I think the car has a 10.6-10.7@126mph as it sits with some more tuning. I still need to clean up the part throttle and acceleration enrichment tables but wanted to get the WOT tables down. I really wanted to see how it would react with the 12.4 A/F ratio. I felt like it was leaning out in the middle of second and third so I want to get this smoothed out and the tune spot on before any nitrous is added. The car still has 3.7 gears which kills my ET and mph. The converter was flashing to 4600 on the logs from idle so it should really pick up on the bottle as well as on the trans brake. The car weighs in at 3600 with driver and fuel. The old lt1 was putting in some decent times and was very consistent. The suspension on the car really works and the car is so easy to drive down the track.
Matt
1st pass (idle launch)
1.569
4.489
6.971
99.119.121
10.955
122.71
2nd pass (had my tuner on the phone and he made the corrections to the VE table to get the wideband corrections under 5%---the car was pulling fuel to keep it at a target A/F ratio of 13.1)
1.573
4.497
6.975
98.38
9.150
11.008
121.06
3rd pass ( I changed the A/F table to target 12.7 instead of 13.1 at WOT--back to where I was on the first pass)
1.563
4.488
6.960
99.18
9.107
10.940
122.85
4th pass(kept the tune the same but foot braked it to 2850rpms--no real change)
1.582
4.505
6.979
99.19
9.123
10.956
122.74
5th pass(changed the target A/F table to 12.7 from 12.6 at WOT---picked up a some hp!)
1.571
4.488
6.948
100.2
9.069
10.873
124.68
6th pass (changed the A/F table from 12.6 to 12.5 at WOT---picked up some more mph)
1.584
4.513
6.974
100.23
9.095
10.899
124.74
7th pass (changed the A/F table from 12.5 to 12.4 at WOT---ran into some issues)
Went to shift from 1st to second and the car shifted then went right to 7600rpms (rev limiter). I let off and coasted the rest of the way down. I am not sure if it is a shifter cable or a trans issue but will have to trouble shoot it to see. The car drove the 20+ miles home OK and shifted fine so I need to investigate.
It was the first time since July 06 that I had this car to the track so I had a blast. I think the car has a 10.6-10.7@126mph as it sits with some more tuning. I still need to clean up the part throttle and acceleration enrichment tables but wanted to get the WOT tables down. I really wanted to see how it would react with the 12.4 A/F ratio. I felt like it was leaning out in the middle of second and third so I want to get this smoothed out and the tune spot on before any nitrous is added. The car still has 3.7 gears which kills my ET and mph. The converter was flashing to 4600 on the logs from idle so it should really pick up on the bottle as well as on the trans brake. The car weighs in at 3600 with driver and fuel. The old lt1 was putting in some decent times and was very consistent. The suspension on the car really works and the car is so easy to drive down the track.
Matt
12-04-2016, 08:20 PM
#3
11 Second Club
Nice runs.. 124 trap speed is right on par with a well thought out street oriented 383 should be..
It will go faster. These setups always take some time to dial in!
12-05-2016, 09:30 PM
#6
Thanks for the compliments. The runs were at Cecil. I am happy with the runs first time out for sure. I talked with FTI today to go over my datalogs and I am getting 10.5% converter slippage in top gear through the traps. I also noticed a slight bit of surging in 2nd and 3rd gear in all the passes but it seemed to get better the more fuel I added. FTI suggested that I go to a 4.11 gear to optimize the performance on the bottle as well as helping it out N/A. The 4.11's will bring the converter efficiency to closer to 5% and also help move the 3600 lb race weight.
I won't be able to get the changes done before the end of the season but will get the gears swapped out and go back to make some more tuning changes.
I won't be able to get the changes done before the end of the season but will get the gears swapped out and go back to make some more tuning changes.
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12-08-2016, 10:46 AM
#9
I figured out the missing/surging issue. #5 spark plug boot was melted completely to the plug. Figure it was like this all summer and I never noticed the missing as I did not floor the car much. That should net me some decent gains once I fix that issue.