[KingLT1]

Originally Posted by FlukeSS

Went to the drag strip again got 3 runs in. All the shift points were raised, airflow adjusted, timing adjusted, among other things.

According to the original logs, Apparently the tune I got after rebuild was an extremely conservative tune. According to calculations of the log only 525 hp at the crank. Don't ask, I have no idea why.

After retune according to log calculations 591 at the crank. Prior tune car was barely moving more air than stock.

Definitely did better on gas pedal was at 100% throttle at 6mph. Also ran with TC and stabilitrak completely off. Also had some decent reaction times even though don't matter on test n tune.

Edit: What I think probably happened that explains my dyno numbers: The shop that rebuilt my engine probably did a max effort tune just to see what the car could do, then gave me the conservative tune I asked for. The new tune I am using now is more or less in between 100% aggressive and 100% conservative. Or at least that is how I explained it to Justin when he was going through it.

Temperature Range: 75-80 degrees F
DA Range: 2500 to 2589
Tire Pressure: 17 PSI warm
Track Condition: Good
Retuned by: Justin L.

Set new best time, best 60 ft, and best ET on the 3rd run. Each run I had was improved from the last. Now I really want that 55 degree day back with -200 to 300 DA.

Getting better...It still seems lazy out of the hole like there is a delay on the initial hit of the throttle. You should be able to 1.6 60ft fairly easy. Next time out try brake stalling it as high as it will go. 2200rpm or so and see what happens.

[FlukeSS]

Originally Posted by KingLT1

Getting better...It still seems lazy out of the hole like there is a delay on the initial hit of the throttle. You should be able to 1.6 60ft fairly easy. Next time out try brake stalling it as high as it will go. 2200rpm or so and see what happens.

That happens between 2000-2500 rpm, Stock torque converter, but the car seems to respond well at 1500 rpm brake torqueing, I was thinking the same thing as you, try to stall it higher around 2000 see if anything changes.

Trying to get over the hesitation from the TC. I'd use Launch control if I could ever figure out how to get the damn thing to work, every time I've tried all I did was spun the tires.

[FlukeSS]

Will be going to the drag strip again this Wednesday. Test out the new tune, and try to work in a 2000-2200 rpm stall on launch.

Apparently my car was peaking on hp at about 525 hp, with the new tune I have the potential to peak at 600hp, and about 570-580 hp in 80 degree weather.

Learned a lot about the data logs from this tuner that readjusted things for me.

Such as the value of a high stall launch. Real time estimate of hp based on data logs.

Either way: TCM retuned with higher rpm shift points, but still relative to the intake system.

From what I gather the original tune might have been intended for an LS rather than an LT. There are differences that I learned from this tuner that sometimes can be difficult for LS tuners to tune the LT's.

Also the recommended BTR cam settings were not set in the tune for some reason. That alone increased airflow. Those recommended settings for the BTR cam are now set in the new tune.

Hopefully I can make something happen this Wednesday.

Looks like there is rain in the morning, but the strip doesn't open until 3pm so we'll see.

[Zracer]

Flukess
I have been following this thread. Our cars are set up fairly similar except I have a 16 1ss with an 8 SPD and have a stage 2 cam motion PD blower cam because I plan on doing an Lt4 blower later. Our cars make similar power and run similar in the same weather conditions and I also run 20" drag radials on factory wheels with the stock converter. I ran last night and went 1.819 60', 5.010 330, 7.575 1/8 mile at 97.48 mph. It was 76 degrees, DA was 2786.49 with 64% humidity.
My car is real sluggish off the line too. I assumed it was sluggish off the line because of the cam but saw where you said your throttle wasn't opening all the way on the hit. When I logged my pedal position and throttle last night I found out mines not opening until I'm running 12 mph. It's out at least a car length before it goes wot. I assume this is in the torque tunning . I'm learning this LT stuff as well. I've been 7.39 at 98 in better weather. We'll get them figured out just takes time.

[wnta1ss]

Originally Posted by Zracer

Flukess
I have been following this thread. Our cars are set up fairly similar except I have a 16 1ss with an 8 SPD and have a stage 2 cam motion PD blower cam because I plan on doing an Lt4 blower later. Our cars make similar power and run similar in the same weather conditions and I also run 20" drag radials on factory wheels with the stock converter. I ran last night and went 1.819 60', 5.010 330, 7.575 1/8 mile at 97.48 mph. It was 76 degrees, DA was 2786.49 with 64% humidity.
My car is real sluggish off the line too. I assumed it was sluggish off the line because of the cam but saw where you said your throttle wasn't opening all the way on the hit. When I logged my pedal position and throttle last night I found out mines not opening until I'm running 12 mph. It's out at least a car length before it goes wot. I assume this is in the torque tunning . I'm learning this LT stuff as well. I've been 7.39 at 98 in better weather. We'll get them figured out just takes time.

When you say throttle not opening, are you talking about just the electronic throttle not opening until 12mph? You are at full accelerator before the car moves, but the electronic throttle is slow to respond to your demand in other words? Because that kind of slow response could indeed come from a torque table in the TCM.

[Zracer]

Yes ,that's what I was thinking.

[FlukeSS]

Originally Posted by Zracer

Flukess
I have been following this thread. Our cars are set up fairly similar except I have a 16 1ss with an 8 SPD and have a stage 2 cam motion PD blower cam because I plan on doing an Lt4 blower later. Our cars make similar power and run similar in the same weather conditions and I also run 20" drag radials on factory wheels with the stock converter. I ran last night and went 1.819 60', 5.010 330, 7.575 1/8 mile at 97.48 mph. It was 76 degrees, DA was 2786.49 with 64% humidity.
My car is real sluggish off the line too. I assumed it was sluggish off the line because of the cam but saw where you said your throttle wasn't opening all the way on the hit. When I logged my pedal position and throttle last night I found out mines not opening until I'm running 12 mph. It's out at least a car length before it goes wot. I assume this is in the torque tunning . I'm learning this LT stuff as well. I've been 7.39 at 98 in better weather. We'll get them figured out just takes time.

Originally Posted by wnta1ss

When you say throttle not opening, are you talking about just the electronic throttle not opening until 12mph? You are at full accelerator before the car moves, but the electronic throttle is slow to respond to your demand in other words? Because that kind of slow response could indeed come from a torque table in the TCM.

Ya so far for me it does hit 100% throttle at 6mph now, I was light footing it before. But trying to get that down below 6mph seems to be near impossible and may have to do with throttle response I figure.

That said however, there's also the 2000-2500 rpm hesitation as well.

Last time at the dragstrip wasn't a good day, bad track conditions, and I guess it wasn't just me everyone was running sluggish relative to their cars.

I didn't post this video publicly because the runs were just that bad.

I also have a bigger problem with heat from the intake system, at the start my IAT is like 150 degrees F. However, the faster I go the lower the temp gets. So I think I definitely need a new CAI with an enclosure. As much as I don't want to blow $1000 on a Cold Air Inductions, I think it will give me the best advantage for the intake system.

That said, with the new adjustments to the tune, my car feels like it pulls strong af in 2nd and 3rd gears in each of the runs.

[Zracer]

If your intake tube is aluminum that's your problem. They heat soak. You don't have to get an inclosed cold air kit. The plastic tubes don't do that.

[FlukeSS]

Originally Posted by Zracer

If your intake tube is aluminum that's your problem. They heat soak. You don't have to get an inclosed cold air kit. The plastic tubes don't do that.

It is aluminum but I felt the tube after a run, and it was barely warm.

Also the CAI I have isn't the best as I'm learning. There's a lot of engine heat that can get into my intake. Rotofab would be a significant upgrade for that, but I wasn't sure if rotofab was completely enclosed. Which is why I'm considering Cold Air Inductions.

[BMLMZ]

Try hitting it off straight idle. My ZL1 never liked to be brought up off idle. Just stab it from idle and let it eat. Try that once and see how it short times.

[Zracer]

The problem with the aluminum tube is it heat soaks at idle and low speeds when air is not circulating thru the engine bay. Do a log while idling and watch the iat temps rise. When you are in the staging lanes in line at the track and doing your burnout it's heat soaking then when you go down the track it cools off and will be cool when you check it after a pass. As far as launching at the track I've tried off idle .

[wnta1ss]

Originally Posted by FlukeSS

Ya so far for me it does hit 100% throttle at 6mph now, I was light footing it before. But trying to get that down below 6mph seems to be near impossible and may have to do with throttle response I figure.

That said however, there's also the 2000-2500 rpm hesitation as well.

Do you mean that you hit full accelerator at 6mph, or that you hit full on the accelerator earlier than that, and it was the electronic throttle that hit 100% at 6mph?

[FlukeSS]

Originally Posted by wnta1ss

Do you mean that you hit full accelerator at 6mph, or that you hit full on the accelerator earlier than that, and it was the electronic throttle that hit 100% at 6mph?

I hit throttle to 100% before that, You can see below I was at 100% throttle at 2mph, but the actual throttle was at 92.5% So I imagine that is the electronic being slow I guess.

[FlukeSS]

Originally Posted by BMLMZ

Try hitting it off straight idle. My ZL1 never liked to be brought up off idle. Just stab it from idle and let it eat. Try that once and see how it short times.

I've done a few runs off idle, but seems the car likes 1500 the most so far. I'll keep trying off idle, 1500 and 2000 just to get more consistent data.

Trying to see which of the launch rpm's limits the hesitation between 2000-2500 rpms.

The recent video above. 4th run was from idle and you can see the hesitation between 2000-2500 rpms when launching from idle. 1st run was from 1800-1900 rpm I believe there was a slight hesitation, but less than from idle, second / third runs were I believe 1500 rpm.