Auto Launch Street tires

[foxxxtman]

Headed to the track tomorrow for the first time in an auto and this car period and I know there has been a lot of discussion as to how best to launch an auto with a stock stall RPM wise but I haven't seen anyone mention how they are throttling it and positioning feet.

Most seem to agree that unless you have an aftermarket converter that you are best to launch from idle, just wondering if you guys are holding on the brake with one foot and then slamming the gas with the other foot as you let off the brake and are you able to go WOT off the bat or will you roast the stock tires? I'm guessing both feet are used, you would have to with a non-stock stall launching at higher RPMs unless you have a trans brake right?

I'm sure I will find out soon enough but just curious as to personal experiences. Seems like the quickest way would be to hold the brake with one foot and get ready to slam with the other vice sliding your foot from brake to gas. I did a bit of searching and reading in the forum here, I know all about the RPMs and converters and stuff like that, just didn't see that specific question answered.

 

[Five Oh Brian]

Hold some rpm's against the brakes at the tree. About 1500 rpm's or so. On the last amber, let off the brake while mashing the gas. If you try launching from idle, leave just before the last amber lights up.

 

[garner]

Start with leaving off idle and see how the car handles it. My car will spin the tires off idle(2.0-2.6 60fts), so I've never tried any higher. But I have my left foot on the brake, then when it hits the 3rd yellow, I let off and hit the gas with my right foot

 

[FIVE-OH]

I have about 100 passes on my car and do a lot of bracket racing, so consistency is huge for me. I can tell you there are no exact answers. It depends largely on your tracks prep, and then your mods. I would lower your pressure to about 25 psi, anything lower will do you no good. Also, do a small burnout to get some heat in the tires, no need for a huge smokey burnout on street tires.

My track happens to prep very well. On the street, my car will roast the tires, at the track it hooks very well. I keep my left foot on the brake, right foot on the throttle. When the car was stock, leaving at idle worked the best. But, once I added my tune it wasn't enough rpm. It now likes leaving at about 1500 or so. I would try idle, just above idle (1000 or so), then 1500 and see what works best. Anything higher will be past the flash point of the converter, or start to give you wheel spin...

Let us know how it goes, with a Mike Rousch tune, and off road pipe (not sure what else you have done), you should be in the low 12's easy...

 

[foxxxtman]

All I have done currently is the Mike Rousch tune and O/R-H, it doesn't even have 2k miles on it yet LOL. So on the track you can mash her to the floor (if prep is good and such) and not light them up typically? I was going from a rolling start yesterday on the street and when I mashed it they lit up pretty well so was just curious. I will try going from idle and from 1k and 1500 just to test which works best for me, knew I was going to have to do that one already.

 

[FIVE-OH]

All I have done currently is the Mike Rousch tune and O/R-H, it doesn't even have 2k miles on it yet LOL. So on the track you can mash her to the floor (if prep is good and such) and not light them up typically? I was going from a rolling start yesterday on the street and when I mashed it they lit up pretty well so was just curious. I will try going from idle and from 1k and 1500 just to test which works best for me, knew I was going to have to do that one already.

On my track yes, I can mash it and it hooks. Don't go by what your car does on the street.

 

[Riptide]

Foxxxtman did you get the new h pipe on?


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[foxxxtman]

I did get the new H-Pipe on yes, no leak and fit good. Only time I've heard any hiss like noise at all is on a cold start when it's inside of my garage where the noise is amplified, soon as it calms back down to idle nothing and driving nothing.

Track got rained out tonight darn it. Maybe next Friday.

 

[808muscle]

300+ passes bracket racing here and Easter Weekend Pro Street 12.90 class winner.

Leaving off idle will get you your best ET.
Leaving with some rpms such as 1500 will get you a better RT but it will slow the car down. The convertor flashes higher off idle than with some rpms.
Deep staging will improve your RT, dont be afraid to try it.
Obviously dont manualy shift the car and turn off all traction controls. With the 5r55 you need to turn off the O/D.
Left foot brake, right foot gas....practice the action of yanking your foot off the brake and slamming the gas beforhand. I literally pull my left leg up into my chest in an exagerated motion. I run the Pro tree so you have no warning when the lights drop.
Seat time improves everything....now go have fun.

 

[FIVE-OH]

Leaving off idle will get you your best ET.
Leaving with some rpms such as 1500 will get you a better RT but it will slow the car down. The convertor flashes higher off idle than with some rpms.

Maybe on a 4.6, but not on a 5.0 necessarly. I can tell you from lots of recent experimenting that is not the case if the car has a good tune, it will want more rpm. If you have LCA's and or relocation brackets it will want more rpm as well. Now, when totally stock, idle was best. My car consistently 60's better by at least a hundreth or two when launching around 1300-1500 then it does at idle. Which equates to a better ET...

 

[808muscle]

Maybe on a 4.6, but not on a 5.0 necessarly. I can tell you from lots of recent experimenting that is not the case if the car has a good tune, it will want more rpm. If you have LCA's and or relocation brackets it will want more rpm as well. Now, when totally stock, idle was best. My car consistently 60's better by at least a hundreth or two when launching around 1300-1500 then it does at idle. Which equates to a better ET...

5.0 motor and new trans might very well be different from the 4.6 and 5r55. Very good point. What is your ET?

 

[2DaDarkZide PR]

I have about 100 passes on my car and do a lot of bracket racing, so consistency is huge for me. I can tell you there are no exact answers. It depends largely on your tracks prep, and then your mods. I would lower your pressure to about 25 psi, anything lower will do you no good. Also, do a small burnout to get some heat in the tires, no need for a huge smokey burnout on street tires.

My track happens to prep very well. On the street, my car will roast the tires, at the track it hooks very well. I keep my left foot on the brake, right foot on the throttle. When the car was stock, leaving at idle worked the best. But, once I added my tune it wasn't enough rpm. It now likes leaving at about 1500 or so. I would try idle, just above idle (1000 or so), then 1500 and see what works best. Anything higher will be past the flash point of the converter, or start to give you wheel spin...

Let us know how it goes, with a Mike Rousch tune, and off road pipe (not sure what else you have done), you should be in the low 12's easy...

What are your 60' times?

 

[foxxxtman]

Made it to the track this evening, it was 75 degrees and 79% humidity by looking at the drag strip information but my best run was a 12.55 (corrected to a 12.40 flat using DA calculator), numbers were as follows:

1.97 second 60 foot
5.39 second 330 foot
8.17 1/8 mile ET
88.61 1/8 mile MPH
12.55 1/4 mile ET
112.87 1/4 mile MPH

I'm just running the O/R-H and Mike Rousch tune on stock pirelli tires. I was hooking pretty good off the line but once I hit 2nd gear it would spin and get a little squirly on me, after that straightened out it was fairly smooth sailing and my runs were pretty consistant.

I found 2 things launch wise, #1 is that my car had it's best run holding the brake and launching at 1500 RPMs and #2 is that you definitely, without a doubt, have to turn advancetrac OFF. My first 2 runs my car actually felt like it cut the RPMs for a short while, then it would kick back like it was shifting again and bark the tires. My fastest (tried it twice with only traction control off) with advancetrac on was a 13.0....

 

[FIVE-OH]

Made it to the track this evening, it was 75 degrees and 79% humidity by looking at the drag strip information but my best run was a 12.55 (corrected to a 12.40 flat using DA calculator), numbers were as follows:

1.97 second 60 foot
5.39 second 330 foot
8.17 1/8 mile ET
88.61 1/8 mile MPH
12.55 1/4 mile ET
112.87 1/4 mile MPH

I'm just running the O/R-H and Mike Rousch tune on stock pirelli tires. I was hooking pretty good off the line but once I hit 2nd gear it would spin and get a little squirly on me, after that straightened out it was fairly smooth sailing and my runs were pretty consistant.

I found 2 things launch wise, #1 is that my car had it's best run holding the brake and launching at 1500 RPMs and #2 is that you definitely, without a doubt, have to turn advancetrac OFF. My first 2 runs my car actually felt like it cut the RPMs for a short while, then it would kick back like it was shifting again and bark the tires. My fastest (tried it twice with only traction control off) with advancetrac on was a 13.0....

Not bad runs, and yes, traction and stability must be off. If you are spinning on the 1-2 shift, but hooking off the line your track must not prep far enough out. You may want to have Mike write you another tune with a slightly softer WOT 1-2 shift...

 

[foxxxtman]

I already sent mike a datalog last night and told him exactly what it was doing, i'm sure he will hook it up. I didn't disconnect my front swaybar either so that would likely help a bit as well.

 

[foxxxtman]

Oh, on a sidenote, I can turn traction control off OR I can turn advancetrac off. Evidently turning advancetrac off also disables traction control? I hold the brake down and hold the traction control button down for about 10 seconds and it says advancetrac off, if i tap it again like I was going to disable traction control it just turns advancetrac back on vice turning traction control off as well. I'm guessing they are paired together.

 

[garner]

Traction control turns off first then advance track is the next step

 

[foxxxtman]

I tried it multiple different ways but from what i can tell I didn't have the option to turn traction off once advanctrac was on, it just turned advancetrac back on and when I turned traction control off first and then advancetrac the traction control off button disappeared. You sure they're not paired? It seems like when you turn advancetrac off that everything goes off, I didn't have any problems after that with the car cutting RPMs or anything.

 

[FIVE-OH]

Foot on brake, two quick pushes of the button puts it in sport mode. Foot on brake, one push of the button, turns off traction control. Foot on brake, hold button for 10 seconds, turns off traction control and stability control.

 

[foxxxtman]

^^ that makes sense. I was holding it down for 10 seconds and shutting everything off then. Makes sense as to why the traction control button off went away. Before I done that the car felt like it was braking or cutting the RPMs and then it would pick back up even with traction control off. After I held it down for 10 sec it was good.