10.50’s 135. Stock zl1. Thoughts?..
 

Saw this on FB

Seems about right for negative DA.

Sheesh

What does a stock ZL1 dyno?

I have seen anywhere from 520-580whp with an average of 540-550whp. In negative DA, the LT4 will run cool enough to get "All the Timing" GM commands in the stock tune and also make more boost. In average air they are normally pulling timing. So I could see a hero pass like this happening. Put that car on a track in 1500 DA and watch it run 10.80-10.90. Put the stock wheels back on it and watch it run 11.2-11.4, right where they are rated.

Cliff Notes

-Full Drag pack is worth 3-4 tenths or better ET reduction and 2-3 mph trap.
- -100 DA probably makes 1-2psi more boost vs 1500-2K


Here is another example. Back in 2017-18 guy posted a time slip of his bone stock 2017 SS A8 running 11.7 @ 119 bone stock down to the run flat tires. Negative DA does wild shit...especially at those north east coast tracks.

Good info thanks king :happy0180:

Density altitude is real for sure. Just to show how density altitude can effect a car this is my 22LT1 this year...

Summer
Density Altitude +2850
60’ 1.850
1/8 7.904@91.24mph
1/4 12.160@115.84mph

Fall
Density Altitude -295
60' 1.798
1/8 7.697 Mph 93.82
1/4 11.849 Mph 118.67

Just another example from my old 01SS Camaro...

Summer
Density Altitude +2265
60'...2.092
1/8...8.580 mph...85.32
1/4...13.197 mph...106.93

Fall
Density Altitude -1245
60 1.958
1/8 8.165 mph 88.14
1/4 12.638 mph 110.04

These comparisons are all about the DA change only. Each 1/4 mile pass had same mods. The little LS1 knocked off the most and I credit that to the super sucker ram air it had as it is a true CAI kit.

As for the ZL1 cars, would you say heat/power loss can be a much bigger issue vs an NA car?

He just dyno’d it. 590hp 553tq on a hub dyno. They read slightly higher. I’ve heard 7-8%. Dsx did the dyno and said it was mufflers, catch can only. Made 10psi. Never been flashed

This is what I had pieced together based on your short response but I just didn’t realize the drag pack picked up that much as well as how much the -DA could do. Good write up for us lesser taught folks!