L99 all over the place!

[2SSARMY]

I just got back from the track. Got a good 30 runs in and man this L99 sure is all over the place. My first 10 runs I ran solid 13.6~.

As soon as I stopped for about 20 mins to watch some other cars with my friends, I started running 14.0~. This kept going for a good 5 runs.

Then I decided to go into tapshift mode to see my luck. I immediately started running 13.8 in competitive mode, then with T/C off I ran a 13.7.

Finally, I kept everything on, no burn out, tapshifting, and ran a 13.5@106, smoking a GT that ran like 15.0 (lol).

Man oh man this car is all over the place. As soon as I started shifting myself I never ran under a 13.8~. 13.5 being my best run of the day, which I was proud of, since my car is an auto and does have 21".

But yeah, just saying, this L99 throws me all over the place. Any ideas why as the day progresses, driving in D makes the car go slower? Every time I hit the track I start off at 13.x~ then end up in 14.0-14.2 in D mode.

[JohnInSoCal]

Did you just try sport mode (M) and no tap shifting ? That should be the fastest with traction control off. D shifting has slower shifts and shifts at a lower RPM I believe. But I am surprised you see a full second difference with a stock tranny tune, I don't recall it making that much of a difference stock.

[Revo1]

20's might tighten up your times a little...

[brAnd7onX]

Is your car completely stock?? I think a tune to get rid of torque management might help out those times a bit.

[djsnoflake]

As the day goes on, it gets hotter which doesn't help anything. Also as I have said eleventy billion times, DON'T do burnouts on tires that aren't drag slicks. It does nothing for your traction.

But hey, it's your money and those 21' tires are only, what, 800 bucks each?

[Mr CLuTcH]

Yeah for the price of each tire....I stay away from burning out. Hey Army, did you ever try cooling your engine in between runs? I've heard it could pull you better times. That and going back to 20s. Nice runs though.

[SGOS252382]

Without knowing your 60' times and trap speeds (seeing the full time slip) your times don't tell us a lot.

Your 60' times (how well you launch) are usually the biggest factor on track times. That could be why your times are all over the place?

And I do a dry burnout. I stay out of the water and just spin the tires for about 15 feet or so. Its just enough to clean off my tires (lots of sand, etc. in our staging lanes) and soften them up a tiny bit. It does help.

[2SSARMY]

Originally Posted by SGOS252382

Without knowing your 60' times and trap speeds (seeing the full time slip) your times don't tell us a lot.

Your 60' times (how well you launch) are usually the biggest factor on track times. That could be why your times are all over the place?

And I do a dry burnout. I stay out of the water and just spin the tires for about 15 feet or so. Its just enough to clean off my tires (lots of sand, etc. in our staging lanes) and soften them up a tiny bit. It does help.

This was my best run:

R//T ... 0.93
60' ... 2.200
330 ... 5.880
1/8 ... 8.873
MPH ... 82.47
1000 ... 11.410
1/4 ... 13.537
MPH. 106.05


And I do dry burnouts too because I put my car on the gravel and dirt when I stop to watch... So calm down guys. I'm not burning the tires to hell... Jeez haha.

And as the day progresses it got colder. When I got to the track it was 73F, then it went down to 59F.

Also I did try to cool the engine down a bit, but when I cooled it down I started getting worse times.

[SGOS252382]

Originally Posted by 2SSARMY

This was my best run:

R//T ... 0.93
60' ... 2.200
330 ... 5.880
1/8 ... 8.873
MPH ... 82.47
1000 ... 11.410
1/4 ... 13.537
MPH. 106.05


And I do dry burnouts too because I put my car on the gravel and dirt when I stop to watch... So calm down guys. I'm not burning the tires to hell... Jeez haha.

And as the day progresses it got colder. When I got to the track it was 73F, then it went down to 59F.

Also I did try to cool the engine down a bit, but when I cooled it down I started getting worse times.

Your 60' time is pretty slow. I can only assume, that on your other runs, your 60' times were similar or slower? You need to get your 60' times down in the 1.9x sec. range. If you do, you'll be running very low 13s (13.2s or so).
Fast 60' times = fast E.T.

And your car should definately run faster as the air gets cooler. 59 degrees is a great temperature for running fast times. But as the temperature get colder, it can be harder to hook up.

I launch my car by holding it on the line with the brake while revving to around 1000 rpms. To launch I just lift up on the brake and roll quickly into the gas. I get consistant 1.9x sec 60' time with this method.

But your track prep will have a lot to do with how you launch your car.

[2SSARMY]

Originally Posted by SGOS252382

Your 60' time is pretty slow. I can only assume, that on your other runs, your 60' times were similar or slower? You need to get your 60' times down in the 1.9x sec. range. If you do, you'll be running very low 13s (13.2s or so).
Fast 60' times = fast E.T.

And your car should definately run faster as the air gets cooler. 59 degrees is a great temperture for running fast times. But as the tempertures get colder, it can be harder to hook up.

I launch my car by holding it on the line with the brake while revving to around 1000 rpms. To launch I just lift up on the brake and roll quickly into the gas. I get consistant 1.9x sec 60' time with this method.

But your track prep will have a lot to do with how you launch your car.

This is exactly what I do. I hold the brake and get it to about 1,000 RPM then let go of brake and go into it. I keep telling myself my not so fast times are due to my rims but who knows.

I am also totally stock. Not one modification..

[SGOS252382]

Originally Posted by 2SSARMY

This is exactly what I do. I hold the brake and get it to about 1,000 RPM then let go of brake and go into it. I keep telling myself my not so fast times are due to my rims but who knows.

I am also totally stock. Not one modification..

What wheels are you running?

Also, are you getting wheel spin? Or are you hooking up pretty well (very little wheel spin)?

If you're hooking up, then it might be your wheels/tires.

A 2.2 sec 60' time is usually associated with wheel spin or wheel hop.

And 13.5 @ 106 mph is a good time. All you need to do is get that 60' time down and you'll be running low 13s.

[2SSARMY]

Originally Posted by SGOS252382

What wheels are you running?

Also, are you getting wheel spin? Or are you hooking up pretty well (very little wheel spin)?

If you're hooking up, then it might be your wheels/tires.

A 2.2 sec 60' time is usually associated with wheel spin or wheel hop.

And 13.5 @ 106 mph is a good time. All you need to do is get that 60' time down and you'll be running low 13s.

Running the P-Zeros that come with the 21".

I get nasty wheel spin, but when I hook I go. Lots of people keep telling me to get slicks, but I am not that much into the track to actually invest that amount of money into it.

[SGOS252382]

Originally Posted by 2SSARMY

Running the P-Zeros that come with the 21".

I get nasty wheel spin, but when I hook I go. Lots of people keep telling me to get slicks, but I am not that much into the track to actually invest that amount of money into it.

Yeah, you need to prevent that wheel spin. Those 21'' P-Zeros have less sidewall than the 20" P- Zeros and that could have something to do with it.

I would advise you to do a softer launch. I would only rev (brake stall) a little bit (maybe 500 rpms or so), and then roll gently into the gas (don't floor it). That should get you off the line a lot cleaner without so much wheel spin.

The higher you brake stall the more likely it will be that you spin the tires. The gentle roll into the gas to launch will also help a lot to keep the wheels from spinning so much.

You might feel like you're launching slowly, but you'll actually be moving faster off the line.

Try that the next time you go to the track and see what happens.

[2SSARMY]

Originally Posted by SGOS252382

Yeah, you need to prevent that wheel spin. Those 21'' P-Zeros have less sidewall than the 20" P- Zeros and that could have something to do with it.

I would advise you to do a softer launch. I would only rev (brake stall) a little bit (maybe 500 rpms or so), and then roll gently into the gas (don't floor it). That should get you off the line a lot cleaner without so much wheel spin.

The higher your brake stall the more likely it will be that you spin the tires. The gentle roll into the gas to launch will also help alot to keep the wheels from spinning so much.

You might feel like you're launching slowly, but you'll actually be moving faster off the line.

Try that the next time you go to the track and see what happens.

I will!
Thank you very much for your help!
It's appreciated!