[travislambert]

Does anyone know how much the wind affects 1/4 mile times?

It looks like he had a pretty strong head wind.

[17CamaroZL1]

Originally Posted by 93oh

Drag racing doesn't work that way my friend. If you run slow et in fast car the track gets "longer" et in crapper should be indicative of higher mph and you're not picking up 4 mph and knocking et down 4 tenths. Mph should be consistent he's either shifting wrong or has one missing about 50 hp.

Is that so? So for instance, if one run you spin half way down the track, and another one you dead hook and accelerate hard the whole way, you're saying you'll have a higher mph on the run that you were melting your tires on? That makes zero sense. If you're spinning, you're not accelerating as fast as you would be if you're not, plain and simple. The only mph that is consistent is the gain in mph between the 1/8 mark and the 1/4 because you typically don't spin. Now the point you meant to make, is that the mph doesn't change as much as the time does between a good launch and a bad one, because you usually don't spin that far as you're traveling pretty slow at launch where most of the tire spin occurs.

[17CamaroZL1]

Originally Posted by travislambert

Does anyone know how much the wind affects 1/4 mile times?

It looks like he had a pretty strong head wind.

It will make a difference, especially in the mph. It will lower the mph more than it will increase the ET. It's kinda like seeing a really fast ET, but a low mph when someone with a fast car lets off the gas before they get to the timing line.

[93oh]

Well he went out there and tried. To answer he naysayer.. I meant to say what I said. After you run few times the 60 foot resulted in lower mph... The car here should trap 122 at least not 119.

[KLR ZL1]

Sure sounds like you had some wheel spin off the line on most of those videos.

[cwebster]

Wow! I go offline for a few hours and I get all this feedback! Thanks everyone!

Originally Posted by detltu

I'm not a hard core drag strip person so I'll let others offer tips. Its very similar to my first run in my ZL1 with my times about half a second slower across the board. Pretty cool that you got to take your grandson out for a ride.

So you're saying there's hope?

Yeah, they very seldom do that. They do have Jr. Dragsters but they're trained teens driving miniature dragsters. I think after watching me from the tower most of the day, he felt comfortable with my driving. He knew right off who I was when I gave him my car number.

Originally Posted by 17CamaroZL1

Thanks for posting! There was a lot of wheel spin from everyone it sounded like and that's what hurt you the most, besides the times you said you bogged. Keep practicing and the bogging will happen less and less. Looking at your slips, the 60 ft is where you have lots of room to drop your times. You'll typically see close to .2 of a second gain in the quarter for every .1 you gain at the 60 ft mark, and you can see that in your slips. Your 12.5 runs had around a 2.3 60 ft and your 12.1 runs were about 2.1 at 60 ft. If you can manage to get your 60 ft down to a 1.6 or so, you'd have some really fast times. I'd think that should be doable, but would take DRs to do it. Question. Did you lower the air pressure in your rear tires any? If not, you'll gain some traction by doing so. I'm pretty sure the HP supplement even had recommended pressures for drag racing.

Yes, you're right about the wheel spin. It was a nice day but we'd just come off sub-freezing temps the previous several days. Track started out in 40s and rose into high 50s by mid-afternoon. The last hour temps dropped dramatically. As you know, colder temps = more power and less traction. It was hard to keep the Custom Launch settings dialed in. I see what you mean, though, about spinning having more effect on ET.

I don't plan on running primarily at the drag strip so I wasn't considering DRs - at least not right now.

So, in terms of bogging the motor, I thought this was being induced by the "Launch Control" system, like it was in my '14 1LE. All but one run were begun under Launch Control. I thought about switching to manual launch but decided to keep testing the automated launch, varying the spin and RPM, to see if it would come around. I wanted to thoroughly test it. Next trip I'll go manual. Should I be feathering the clutch at all on manual launch?

I did not drop the pressure in my tires. In fact, I think they were set higher than recommended at the dealer and I just left them as-is. Worse yet, I did read the supplement and had planned on doing it but when I got there I was anxious to get started and it completely slipped my mind.

Originally Posted by 93oh

All in the launch ... I ran 2.1 short times in my aod mustang in 1990. Appreciate video. You at sea level?

Yeah, this beast is SO powerful once the RPMs are up that there wasn't one car I didn't gain on after I got going down the track. I caught and passed several that had me off the start.

It's pretty close to sea level I think. On the way there I travelled over bridges over the intra-coastal waterway.

Originally Posted by Can'tHave2MuchHP

Yeah, order a set of NT05Rs in 315/35/20 and you'll cut 1.6s and less in no time.

I am actually looking at getting an extra set of rims and tires but not for the drag strip. I want to run the road courses so I was thinking along the lines of compounds that would work well for turns primarily but haven't decided on the rubber yet.

Originally Posted by detltu

For a manual on his first time out with the car I don't think there is anything wrong with that. It takes a lot of work to get times down on stock tires. There is a reason people quickly switch to DRs.

Thanks. I thought I did pretty well too, considering this was only my 3rd trip to the drag strip ever. The other 2 trips were back in 2013 and 2014 with my 1LE. Best ET with the 1LE was 13.1. I'm sure I can do better, even on these stock tires.

Originally Posted by 93oh

Ehh true but maybe he has never drag raced. It's all relative but the mph sucks too so it's confusing me all the way around.

I wouldn't say never but I definitely lack experience at the track and in this car with this setup.

Originally Posted by 17CamaroZL1

The manual ZL1 is actually advertised as a high 11 second car. GM says it will do 11.8, so I'd say he did pretty good for his first time out. Plus I feel there's more traction to be had out of the stock tires even. Whether it's temperature, track prep, air pressure, burn out, or launch adjustment, or maybe even a little of it all. The mph is down compared to the 125 GM says the manual will do, but with a better 60 ft, that'll go up too.

I definitely was gaining on everyone near the big end. In fact, for most of the track, once I got out of the hole. I'm seeing quite clearly that improvement in the first 60 ft will bring my times down dramatically. If I could just keep from bogging and slipping...

I'm thinking a combination of tire pressure, launch parameters, and timing (launch and shift) will do the trick. I feel certain that mastering these could put me below 11.8 on stock tires.

Originally Posted by 17CamaroZL1

Looks like his best mph was a 121.66 with a 12.22 ET. So if he gets the 60 ft time down so that he can run the 11.8 that GM claims, he should be close to the 125 they say the manual will do.

Why does MPH matter? If my ET is lower than the other guy but his speed is faster, does that give him bragging rights? Is that the fastest speed that they clocked with radar or is it calculated?

Originally Posted by Snowblind

Thanks for sharing OP

Practice and tires and more practice, did you happen to check what the DA was ?

I like sharing because it allows me to leverage the knowledge and experience of everyone who participates in the discussion. I'll get more practice on the next available track weekend. It's kind of hit-or-miss this time of year. The weather is usually mild here in Eastern NC but it's fickle and you often don't know if the track will be open until the day before. Even if it's clear they won't open if its too cold or damp.

I assure you that DA was the last thing on my mind. I believe the dew point was high and barometric pressure still low as we were still close to a storm front.

Originally Posted by 506JTF

Great info! Stick with it. These things are very hard to launch with or without launch control. Bogging off the line seems to be an issue that stuck with the zl1 from 2012.

It was there in my '14 1LE so bad that I divorced launch control and got much better times with manual launch. The season closed before I could get good at it, though.

Originally Posted by travislambert

That's a lot of work to post everything. Thank you!

I know the launches are incredibly difficult with the manual. I've only made two passes with my car, but your 60' times are as good or better than mine. With a little practice I'm sure you'll get it mastered.

I have to say though I'm a little disappointed overall. I'm no drag racing expert or anything, but I was expecting the ZL1 MPH times to be a little faster based on the times I got from my 2SS (with a stock LT4 crate engine).

You're welcome. I'm glad you enjoyed the content. I'm hoping that my openness will prompt others to share too. That way we all learn something and get better. Besides, it's fun to watch others do what I love to do and see what they do differently.

Sounds like quite a machine, your LT4 2SS. It was probably a bit lighter than the ZL1.

Originally Posted by 17CamaroZL1

Is that so? So for instance, if one run you spin half way down the track, and another one you dead hook and accelerate hard the whole way, you're saying you'll have a higher mph on the run that you were melting your tires on? That makes zero sense. If you're spinning, you're not accelerating as fast as you would be if you're not, plain and simple. The only mph that is consistent is the gain in mph between the 1/8 mark and the 1/4 because you typically don't spin. Now the point you meant to make, is that the mph doesn't change as much as the time does between a good launch and a bad one, because you usually don't spin that far as you're traveling pretty slow at launch where most of the tire spin occurs.

This is interesting! I never thought of it this way but it makes sense.

Originally Posted by 17CamaroZL1

It will make a difference, especially in the mph. It will lower the mph more than it will increase the ET. It's kinda like seeing a really fast ET, but a low mph when someone with a fast car lets off the gas before they get to the timing line.

Come to think of it, there was about a 10 mph wind coming from a nearby storm front - saw it on the news in the morning.

Originally Posted by KLR ZL1

Sure sounds like you had some wheel spin off the line on most of those videos.

I thought I'd dialed most of that out. All I remember was a chirp off the launch after the first 3 or 4 runs. There might have been more during the sifts. I'll go back and review the videos anyway. I've got a lot to review and analyze before my next visit to the track.


Thanks for all the input, guys and gals!

--Cal

[2NASSTY]

Good job on taking your ZL1 out there and making a lot of runs. It will get better with practice and working on each area of the run. Especially on factory rubber which is very difficult to do in a heavy blower car making this kind of power.

Lower your tire pressure down to 22-23 lbs. get a a good 2nd gear burn out. Not 1st gear. Lower wheel speed in 1st gear which won't heat the tires. Try slipping the clutch off the line at 2000-2500 rpm on factory rubber. Once the nose comes up, gradually release the clutch while applying gas. This will take practice. If you let of the clutch too soon without enough gas you will either bog or wheel hop.

Not sure where the factory rev limiter is on this new ZL1. Guessing it's 6500 rpm. Make sure you are shifting all The way up to 6300 on each shift. Very important. This is where your MPH will come from.

After you get this all down after 20-30 runs start working on the tree. That's another chapter in a manual.

I noticed you made many runs. Make sure you let this car cool down at least 20 min before each run. Your IAT2 temps where probably sky high if you were hot lapping this thing. The compeuter will pull timing once the IAT2 temps reach a certain temp. Up to 50-70 HP loss. I don't care how many heat exchangers are installed.

Have fun with it Man. Good job again

[Jeffro19]

Nice to see someone take there ZL1 to the track for some actual times. They will get better once you get used to the car. Thanks for the videos!

[Can'tHave2MuchHP]

Originally Posted by 2NASSTY

Good job on taking your ZL1 out there and making a lot of runs. It will get better with practice and working on each area of the run. Especially on factory rubber which is very difficult to do in a heavy blower car making this kind of power.

Lower your tire pressure down to 22-23 lbs. get a a good 2nd gear burn out. Not 1st gear. Lower wheel speed in 1st gear which won't heat the tires. Try slipping the clutch off the line at 2000-2500 rpm on factory rubber. Once the nose comes up, gradually release the clutch while applying gas. This will take practice. If you let of the clutch too soon without enough gas you will either bog or wheel hop.

Not sure where the factory rev limiter is on this new ZL1. Guessing it's 6500 rpm. Make sure you are shifting all The way up to 6300 on each shift. Very important. This is where your MPH will come from.

After you get this all down after 20-30 runs start working on the tree. That's another chapter in a manual.

I noticed you made many runs. Make sure you let this car cool down at least 20 min before each run. Your IAT2 temps where probably sky high if you were hot lapping this thing. The compeuter will pull timing once the IAT2 temps reach a certain temp. Up to 50-70 HP loss. I don't care how many heat exchangers are installed.

Have fun with it Man. Good job again

Chett here knows his stuff with drag racing. His manual runs are awesome.

Just keep practicing, but take it easy on her, ya don't wanna replace the clutch at 3,000 miles

[bobby35ny]

Originally Posted by 17CamaroZL1
Looks like his best mph was a 121.66 with a 12.22 ET. So if he gets the 60 ft time down so that he can run the 11.8 that GM claims, he should be close to the 125 they say the manual will do.


Why does MPH matter? If my ET is lower than the other guy but his speed is faster, does that give him bragging rights? Is that the fastest speed that they clocked with radar or is it calculated?

I don't think 17CamaroZL1 was trying to put you down or anything.

I was looking at the same thing he was, Your first time out there, The ET really didn't matter, I was looking at the big end MPH, I wanted to see 125-126 too. The MPH is a good indicator of HP. Unless you had a super crazy headwind at those temps I would think your MPH should have been at 125.
-Bobby

[396ssrat]

Kudos for getting to the track. The results are not unexpected at all, you will improve with seat time. Your life would be more fun if you invest in a good set of drag radials. Don't worry so much about mph as it will improve once you get your launch and shift points dialed in.
Sticky tires are your friend here more than anything else at this point. With time you will vastly improve your track times.
Have fun and stay safe. Great job!!!!

[17CamaroZL1]

Originally Posted by bobby35ny

Originally Posted by 17CamaroZL1
Looks like his best mph was a 121.66 with a 12.22 ET. So if he gets the 60 ft time down so that he can run the 11.8 that GM claims, he should be close to the 125 they say the manual will do.


Why does MPH matter? If my ET is lower than the other guy but his speed is faster, does that give him bragging rights? Is that the fastest speed that they clocked with radar or is it calculated?

I don't think 17CamaroZL1 was trying to put you down or anything.

I was looking at the same thing he was, Your first time out there, The ET really didn't matter, I was looking at the big end MPH, I wanted to see 125-126 too. The MPH is a good indicator of HP. Unless you had a super crazy headwind at those temps I would think your MPH should have been at 125.
-Bobby

Right. Thank you! I'm pretty sure he understands that. I had actually been bragging on him in earlier posts. I think he was just asking why everyone seems so focused on the mph more than the ET. I only brought up the 125 because someone was saying his mph sucked and I was taking up for him saying I thought he did good since he almost managed a 122 on his first track day. I feel even stronger about that after finding out he may have had a 10 mph headwind.

[2NASSTY]

The MPH will come with practice, quick shifts, shifting consistently on each gear change at 6200-6400 rpm. The biggest factor will be -DA on MPH. Gotta have good air

[93oh]

Air doesn't get better then January. It's pulling shifts at 6200. Launch tc off at around 1000 and squeeze out and slowly bury it and shift at 6200, bang shift into second as so on should go faster. He did well but saying mph is way off. Indicative of short shifting. Also, yes hot lapped it so car probably had its tongue hanging out.