Best way to launch RS7 at the drag strip?

[kevinw23]

I am coming from a 2013 S6, and being that it was a double clutch, I'm assuming thats why I feel a difference. Once I engaged LC, the S6 staying in launch mode for a few seconds.
When I tried it last night with the RS7, I was in sport mode, dynamic, and I held the traction control button until it was completely disengaged. I then slammed the brake to the floor and then the accelerator. The car immediately shot forward at about 2,800 RPM give or take. It almost felt like all I was doing was "power breaking" and not really launching. Heading to the track in a few weeks and just want to get the launch down. Any input would be appreciated.

[MadAboutCars]

The RS7 has no way to disengage the torque converter, so it is pretty much a brake launch, using torque converter slip. What the LC procedure does do is enable AMAX mode, which will give you much faster gear changes without the usual cackle between gears.

[3rdBNCC]

Interesting to see this as I just saw a similar question on another forum. As stated above by madaboutcars, the RS7 does not have traditional LC. The same procedures are apprarently required though to enable AMAX. I cannot speak for other RS7 owners but in my case a good launch requires perfect timing. A feathering in of the throttle to raise the RPMs to or around 2500 when releasing the brake. Again with my car, the gas pedal must be floored right after launch. Any slight let up on the pedal my AMAX does not activate properly which equates to a poor pass on the track.

When I get back to my office I will post two videos. One with AMAX working flawlessly and one without AMAX. You will be able to tell the dramatic difference.

[kevinw23]

That would be great, thanks. Just coming out of an S6, it just feels so different. I have about two weeks until the tracks open up here, so I have time to mess around with the car. We are going to run the car stock, and then stage 1 tune hopefully on the 3rd. Then, we will install the downpipes and go stage two in the following few weeks. After that, I'm hoping to push things a little further. Can't wait to see your videos.

[3rdBNCC]

That would be great, thanks. Just coming out of an S6, it just feels so different. I have about two weeks until the tracks open up here, so I have time to mess around with the car. We are going to run the car stock, and then stage 1 tune hopefully on the 3rd. Then, we will install the downpipes and go stage two in the following few weeks. After that, I'm hoping to push things a little further. Can't wait to see your videos.

Until I have a chance to post both videos, you can go to post 85 on the sticky at the top of this section on 1/4 mile database. That post shows my 10.344 pass. Obviously AMAX was working lol.

Watch the video closely on the launch. Not a lot of violence, nice and smooth lift into take off

[3rdBNCC]

Heelbuff without AMAX
https://youtu.be/06LjfWqgu6o

Mine with AMAX
https://youtu.be/p35Qm8oSX1Q

[cobrario]

Heelbuff without AMAX
https://youtu.be/06LjfWqgu6o

Mine with AMAX
https://youtu.be/p35Qm8oSX1Q

so this may sound like a really dumb question but all the AMAX talk I've never seen it explained what AMAX is and is that exclusive to APR? I thought I read it was shifting without boost bleed but I may be way off the mark there.

[3rdBNCC]

so this may sound like a really dumb question but all the AMAX talk I've never seen it explained what AMAX is and is that exclusive to APR? I thought I read it was shifting without boost bleed but I may be way off the mark there.

This is an explanation from Kouzman on another forum: "Amax is what the Germans are referring to as Acceleration MAX. It is a shifting strategy to ensure the fastest acceleration possible. Some stage 2 cars have shown issues with this mode where they cannot longer activate it and the car is significantly slower. It has occurred mostly on stage 2 cars and so far the most likely scenario is the huge amount of extra torque the stage 2 produces and it might be setting some kind of safe mode. A few tuners are researching it but the process is extremely slow."

There are other explanations on this forum as well. To my knowledge only APR cars have suffered the loss of AMAX

[kouzman]

Interesting to see this as I just saw a similar question on another forum. As stated above by madaboutcars, the RS7 does not have traditional LC. The same procedures are apprarently required though to enable AMAX. I cannot speak for other RS7 owners but in my case a good launch requires perfect timing. A feathering in of the throttle to raise the RPMs to or around 2500 when releasing the brake. Again with my car, the gas pedal must be floored right after launch. Any slight let up on the pedal my AMAX does not activate properly which equates to a poor pass on the track.

When I get back to my office I will post two videos. One with AMAX working flawlessly and one without AMAX. You will be able to tell the dramatic difference.

Your launch seems to work perfectly since you are cutting 1.50s! The questions that I have... did you play with the tire pressures or not? what psi do you have hot at the strip?

[DGVR6]

so this may sound like a really dumb question but all the AMAX talk I've never seen it explained what AMAX is and is that exclusive to APR? I thought I read it was shifting without boost bleed but I may be way off the mark there.

This is a good detailed explanation of amax by sean.
Even though it's for DSG, same principle applies to the ZF in terms of power output through shifts

Quote from: Sean@APR

A normal shift de-rates the engine by telling the ECU to pull timing. It does this to prevent free-revving and to lower the torque at the clutch to make shifting easier. It has the engine de-rate while it's opening the first clutch. The engine free-wheels for 50ms or so while the second one is being closed and then the TCU tells the engine to bring back the power.

When in this mode, the TCU keeps the beans on the entire time. There is no de-rate at all. It controls the engine RPM by having both clutches engaged in the linear (slip) region together while it transitions between the two. The upshot of this is that there is no de-rate, the engine is making full power the entire time and is transmitting it to the ground even during the shift. The downside is that it's extremely delicate. If the transition time is too fast, the clutches won't slip enough, will be working against each other and will rip themselves out of the transmission. On the other side, if the transition time is too slow, the engine will free rev, hit the limiter and de-rate via the rev limiter. It comes back as soon as the clutch closes a bit more and pulls it off the redline, but it still spent some time in de-rate.

[3rdBNCC]

Your launch seems to work perfectly since you are cutting 1.50s! The questions that I have... did you play with the tire pressures or not? what psi do you have hot at the strip?

Didn't touch the tire pressures (mine are a bit high if anything 45 psi). I drive an hour and 20 minutes to get to OSW, so the car has to cool down a bit when I get there. Typically my first two runs aren't great 10.8x to 10.6x due to wheel spin but as the night wears on, the crew does a better job with the track. The glue is quite heavy and that's when I am able to cut the 1.5s that you are seeing.

One other thing that seems to puzzle many people about my setup is, my car sits pretty low. Basically all 4 tires are tucked in comfort. Guys have said if it was raised back up to stock height, I would run a better time because it would allow the car to properly squat at launch. Not saying I disagree necessarily but in my case it seems to work out just fine. Not much room in the rear wells for wheel hop neither so I don't get much of that.

[kevinw23]

Awesome info here. Thanks guys. I will start practicing, as we are less that two weeks away from the tracks opening up north.....weather permitting.

[kouzman]

Didn't touch the tire pressures (mine are a bit high if anything 45 psi). I drive an hour and 20 minutes to get to OSW, so the car has to cool down a bit when I get there. Typically my first two runs aren't great 10.8x to 10.6x due to wheel spin but as the night wears on, the crew does a better job with the track. The glue is quite heavy and that's when I am able to cut the 1.5s that you are seeing.

One other thing that seems to puzzle many people about my setup is, my car sits pretty low. Basically all 4 tires are tucked in comfort. Guys have said if it was raised back up to stock height, I would run a better time because it would allow the car to properly squat at launch. Not saying I disagree necessarily but in my case it seems to work out just fine. Not much room in the rear wells for wheel hop neither so I don't get much of that.

You see this is exactly why i am asking. I am running as low as 31psi hot, which is substantially lower than my normal pressure. A taller tire can definitely help with the teap speeds. This year i will insist on running with tire pressure in the 40-45 psi hot.... i have a feeling that the
car will run better. If i can even touch the 1.50 60fts i will go much much faster. I did my best 10.59 with a really average to bad 1.73sec 60ft

Thanks for the reply!

[3rdBNCC]

You see this is exactly why i am asking. I am running as low as 31psi hot, which is substantially lower than my normal pressure. A taller tire can definitely help with the teap speeds. This year i will insist on running with tire pressure in the 40-45 psi hot.... i have a feeling that the
car will run better. If i can even touch the 1.50 60fts i will go much much faster. I did my best 10.59 with a really average to bad 1.73sec 60ft

Thanks for the reply!

No problem, anytime. Wish some of you NY guys could come down here and run with us FL boys.

Your time kicks ass. With a 1.5x 60' you would be damn close to mine. Must be a Daytona Gray Pearl thing!!

[cobrario]

I'm heading to the track Saturday for some baseline runs and I was hoping for a little clarification here- am I understanding correctly that although we don't have LC, the traction control needs to be completely disengaged to allow the car to increase the "torque convertor stall speed" to about 2800 rpms? I've tried it just in dynamic (without the traction control off) and I can't the car to come up over about 1500 without lurching.

Thanks!

[kevinw23]

From what I am being told by guys on here that have had success, is that you need to completely disengage traction control (holding the button down for a few seconds), sport mode, hard braking, and then you feather the gas to about 2,500 rpm. Some people say that the car should be at comfort height and others haven't used that. I am also going on saturday, and am going to use all of the above, mess around with the ride height and tire pressure, and see what happens.

I am hoping to run a few times stock, then take a break and flash the car to stage 1 on site and do a few more runs.

[cobrario]

I am hoping to run a few times stock, then take a break and flash the car to stage 1 on site and do a few more runs.

Should be good weather for making power, if it'll stick- whose software are you using, if you're flashing there i'm guessing Uni?

[kevinw23]

yes

[cobrario]

yes

that's what I'm going with after this Saturday, let me know how you run, are you using the 1+ ?

[kevinw23]

I will definitely post up results. I'm going to start a thread from stock to stage 2+, documenting each stage with track and dyno results. Should be fun. I assume just stage 1, not even sure what 1+ is.

[cobrario]

standard stage 1 is 91 octane, 1+ is stage 1 for 93

[3rdBNCC]

I set up the "Individual" drive mode in my car for the drag strip. Everything is set to dynamic except for the air suspension. It is set to Comfort. I haven't had much luck decreasing tire pressure, in fact my best runs have been at around 45 psi on all 4 tires. Not saying you won't have better results lowering yours.

[kevinw23]

Oh wow, didn't know you ran that much pressure. Good to know. We are going to run the stage 1+ file so that I can use premium fuel.

[cobrario]

I plan to raise it up to get some weight transfer too and my plan for tire pressure is to stick with what I get there with- although the ambient on Saturday here is only supposed to be 46 deg so traction may be an issue and tire pressure may play a part- I just plan to arrive, park and wait until they call us to run and see what she does.

[cobrario]

Oh wow, didn't know you ran that much pressure. Good to know. We are going to run the stage 1+ file so that I can use premium fuel.

I'm looking forward to see what you can do, I've only seen one other Uni car post slips on the forum so you'll immediately double the data pool

[3rdBNCC]

I'm heading to the track Saturday for some baseline runs and I was hoping for a little clarification here- am I understanding correctly that although we don't have LC, the traction control needs to be completely disengaged to allow the car to increase the "torque convertor stall speed" to about 2800 rpms? I've tried it just in dynamic (without the traction control off) and I can't the car to come up over about 1500 without lurching.

Thanks!

No traditional LC. Will need to feather into the launch. Still have to disengage traction and brake lock to enable AMAX. I have to keep a firm foot on the brake to prevent lurching if I am looking for a good reaction time. But typically I launch when I feel the car is ready and do not even apply the gas until the tree is on the way down. Feather in the gas to reach around 2500 rpm, release the brake, stab it hard and hold on tight.

[Chris Morales]

It should also work just flooring the gas with the brake held firmly. There is a rev limiter that for my S8 kicks in at 2400 rpm when I'm brake torquing. No need to feather the gas for launch, though experimentation may prove that works better (doesn't for me).

[3rdBNCC]

It should also work just flooring the gas with the brake held firmly. There is a rev limiter that for my S8 kicks in at 2400 rpm when I'm brake torquing. No need to feather the gas for launch, though experimentation may prove that works better (doesn't for me).

I have tried that as well. I guess I should have phrased that a bit differently and said... What has worked best for me personally, is to feather into the launch. As we have all seen, these cars can and do react differently from one another. I can consistently hit 1.5-1.6 sec 60' with my car launching this way though.

[decedre]

I have tried that as well. I guess I should have phrased that a bit differently and said... What has worked best for me personally, is to feather into the launch. As we have all seen, these cars can and do react differently from one another. I can consistently hit 1.5-1.6 sec 60' with my car launching this way though.

Where / who did your tunes? Also in Florida (further south) and am just curious.

[3rdBNCC]

Where / who did your tunes? Also in Florida (further south) and am just curious.

EPR in Vero Beach is doing APR tunes now.

[Serpent]

What I normally do is turn off traction control, make sure steering wheel is pointing straight, full brake, full acceleration and car squats and revs to about 3000 rpm and GO!

[Serpent]

I'm heading to the track Saturday for some baseline runs
Thanks!

You need to come to Blackbenzzz(on this forum) track day on March 25th at MIR.

[cobrario]

You need to come to Blackbenzzz(on this forum) track day on March 25th at MIR.

I'll see if i can work that out, after this Saturday I'll be getting software, was wanting to try Uni but I may end up going APR after all- just wish I had a dealer closer to me than Lorton- that's a haul from Winchester. I guess on the bright side I'd have about 80 miles to enjoy the new found juice

[Serpent]

I'll see if i can work that out, after this Saturday I'll be getting software, was wanting to try Uni but I may end up going APR after all- just wish I had a dealer closer to me than Lorton- that's a haul from Winchester. I guess on the bright side I'd have about 80 miles to enjoy the new found juice

I have APR stage 1 tune and I like it. I'm contemplating stage 2 right now.

[3rdBNCC]

I have APR stage 1 tune and I like it. I'm contemplating stage 2 right now.

Been on APR Stage 2 for 2 months now and love it. I guess the only fear is the AMAX issue, but looking at the few incidents that have happened. It seems that some cars lost AMAX immediately after changing from Stage 1 to Stage 2, meaning they never actually ran right after the upgrade. Maybe coincidental but look at heelbuff's car and the car he witnessed last weekend. Not saying this would happen to everyone because obviously it hasn't but it just seems odd to me and a possible pattern for the problem.

I went straight from stock to Stage 2 and thankfully so far no issues.

[Serpent]

Been on APR Stage 2 for 2 months now and love it. I guess the only fear is the AMAX issue, but looking at the few incidents that have happened. It seems that some cars lost AMAX immediately after changing from Stage 1 to Stage 2, meaning they never actually ran right after the upgrade. Maybe coincidental but look at heelbuff's car and the car he witnessed last weekend. Not saying this would happen to everyone because obviously it hasn't but it just seems odd to me and a possible pattern for the problem.

I went straight from stock to Stage 2 and thankfully so far no issues.

Interesting, thanks for that! I haven't heard of any C7.5 cars suffering from AMAX issue, maybe i'm wrong. Stage2 will still give me the extra boost from stage1 on my daily drives, even without AMAX which only engages if you 'launch' the car - from my understanding.

[3rdBNCC]

Interesting, thanks for that! I haven't heard of any C7.5 cars suffering from AMAX issue, maybe i'm wrong.

Just a theory I have... And to my knowledge, you are correct, no post facelift cars have suffered from this issue.

[cobrario]

I went straight from stock to Stage 2 and thankfully so far no issues.

did you run your car stock? Curious if your car was a freak then too?

[3rdBNCC]

did you run your car stock? Curious if your car was a freak then too?

Lol. No actually, I only ran it on the street a few times.

[cobrario]

Lol. No actually, I only ran it on the street a few times.

well I hope the luck of the DGP cars follows for me as well!