2MCHPWR

iTrader: (10)

hi all - i went to a track rental weds at atco, NJ.
first time dragging the zl1 (but i have many years drag and RR experience).
But i had weird launch issues (below).
2013 M6 Zl1
3955 lbs (no driver) with pass seat removed and lighter weight wheels/tires.
1/4 tank of gas. Torco additive.
MT ET Street 305/45/18 25 psi and 255/18 goodyear RSA's. (these wheels were from my firebird, and the whole wheels/tires setup saved 75 lbs).
The only mod is rotofab CAI.
Probably making about 525 hp at wheels. I did dyno once and it was 507 but there was KR and it was only making 19 degrees timing; i think due to winter gas.

At the track, i turned all nannies off (hold button 10 secs until both lights illuminated); did this all day except for 2 times to experiment with the factory "LAUNCH CONTROL" (details below).

pass #1 right off street 11.9, 3500 launch
pass #3 11.6. bam. happy as pig in ****. i think rpm was 3500 or so.
Since then i started raising the launch RPM but consistently had major bog.
Yes the track was sticky as ****.
4500 - bog
5000 - bog
5500 - bog
6000 - bog.
all above were 12.0 times.
ok time to regroup.
why is it bogging? it has power to spin the wheels! i am thinking torque management killing power. TM is built into the stock tune/ECU.

so then i try to use ptm (performance traction management) 5 with Launch Control. i had doubts and i was correct.
first time with LC - bog
2nd time with LC - bog

ok now what? so i think slip the clutch ...
first time with like 5k rpm launch (no more LC) - smoked the clutch.
2nd time slipping it a little less than previous - smoked the clutch.

now i'm annoyed that i can't reproduce the 11.6 and smoked clutch.
rest.

new idea - lower RPMs again (approx 3500) and NO burnout!
i did clean off the tires in 1st gear in the water box for like a second.

first time - slight spin 1.8 short time and 11.6
2nd time - still no burnout! - slight spin, 1.79 and 11.6
3 and 4th time - no burnout - all 11.6's.

all had slight spin.
so now i'm greedy. let's try a small burnout with that lower 3500 rpm launch.
bog - 1.8 and 11.7.
2nd time with above - same result

so i'm done for day. mostly happy with a slew of 11.6's but still i know or feel the car has more in it if i can get a real launch.
the first launch of the day was 1.748 but couldn't reproduce. 2nd best was 1.788, followed by 1.798 followed by 1.830 ( and ironically my fastest ET was from that slowest 1.830 short time).

If i could get a 1.6x, that could be a 11.4 which would be pretty insane. I think i will lower air pressure to 20psi and stick with the low 3500 RPM launch and see what it does.

1RawTA

iTrader: (1)

Good MPH, The car is moving. I would assume the car isn't in warranty anymore? why dont you throw a tune on it get rid of all the TQ management and add a few extra HP.. Prob run 11.3 maybe even 11.2 with a tune

2MCHPWR

iTrader: (10)

17 more months of warranty. thats why certified GM pre-owned

very hard not to put smaller pulley on and tune it. temptation

murphinator

iTrader: (2)

hit it with a little dry shot ( DA in a bottle) nobody can tell you did that warranty wise and I can tell you from experience roots sc cars will pick up more than you would ever expect from just a little 35-50 shot.

MonmouthCtyLS7

iTrader: (6)

very nice...

454z06

iTrader: (-1)

Nice!