How to use F8X M3/M4 Launch Control - Facts and Fiction

[xxx_mina]

I've already done like a ton of passes at the drag strip and the street . Here is what I've learnd between me JB4 M4 and my Buddy eazrad with completely stock M4:

1. You can launch control in any throttle, suspension, and steering setting. Even efficient and comfort. Some say they prefer to use efficient for a softer launch and then use M button to switch to sport plus after launch(i have not proven or disproven this yet)

2. Do not launch in sport plus Suspension . You will spin and probably crash vise versa comfort suspension at speeds over 130 mph is very unstable (in my opinion)

3. How launch control works. You turn off traction, set transmission to S3 press the brakes and floor it and hold both brakes and gas down. then lower rpm to lowest setting 2200(if needed) let off the brakes and hope you grip. Then the car will shift on its own even though your in S3. It shifts first into second pretty early but I've cut 1.80 60ft so im okay with that. You don't need to shift at all but you can if you want to after it shifts into second on its own. My friend ran 11.68@121 with a 1.83 60ft in completely stock M4 using that method and shes a girl. She let the car shift itself the whole way. Ps: JB4 users, i reccomend you set your max boost in first gear to 6psi. That will lower whatever your first gear boost by 6psi. With better tires or sticky track try increasing RPM or Increasing first gear boost on JB4.

4.Warming up the tires. 1. Set your tires to 29-32psi. 2. While your car is fully stoped and your foot off the brakes and your in S3 gear 1 (our cars don't move till you give them gas) Floor it as hard as you can. The car will rev up to 4k,the clutch will catch and the wheels will spin. If you get wheel hop during launch , lower air and try to burn out harder. I recommend you launch in comfort suspension.

5. Warming up and cooling down . You don't really need to drive any amount of miles. You just need to warm up the car for it to activate. I've activated it at 200 degree oil temp in sfl. At the track after a pass, i get back to staging, leave car running for a min or two to cool the turbo then completely turn it off to cool the transmission. If you don't do this and if you try to hot lap it. Your car will tell you the clutch is too hott and go into limp mode around 3rd gear and kill your run. On the street just drive the car for a min or so on cruising to cool transmission and engine. Track tends to be hotter. Feel free to turn off your car between passes / races. Launch control will work again as long as the car is warm. If there is a huge break between passes. Just keep an eye on oil temp and make sure the gauge is reading in the 200s. Leaving car on will keep your transmission hott and your car will limp mid pass.

I've tested all this on both the track and the street it works. I've hooked in the street very well and ive cut 1.80 60ft at the track and ran 11.34@125.4

Ps: if you use launch control and decide to let off or hold back throttle/feather the gas during the launch... Your car will complete disengage the clutch and ruin your pass. You have to keep the gas pedal down when you launch or the car will disengage the clutch. Also you can't launch control twice in a row but you can activate launch control turn it off(don't use it just let off the gas) and activate it twice in a row.

Please make it a sticky.

Mina

[Rx7andy]

Thanks for the good tutorial.

[Longbow64]

Absolutely right about setting the RPMs (especially in temps less than 65), suspension settings, and info on heating up the tires. First car with a DCT, so I wasn't sure how to actually do this.

[TurboSid]

do you adjust your max boost for 2nd? i spin even in third gear on e85/93-30/70

[CanAutM3]

Good recommendations

That 11.68 @ 121mph from your friend in a stock F8X

Quite impressive

[xxx_mina]

Originally Posted by TurboSid

do you adjust your max boost for 2nd? i spin even in third gear on e85/93-30/70

No i dont, if you warm up your tires like i reccomended and dont spin in first, you most likely wont spin in 2nd... maybe a chirp... on the track you should'nt at all . I could be wrong , you might need to limit boost in 2nd...but the way the car shifts into 2nd early on its own might also be the reason i dont spin in 2nd. your probably riding first out and shifting into 2nd higher in the power band. Try it, play around with it and see...

Originally Posted by CanAutM3

Good recommendations

That 11.68 @ 121mph from your friend in a stock F8X

Quite impressive

1. It was a really cold day for south florida, in the 40-50s , yet the track was still warm and sticky- Perfect Track Day

2.He has the M4 with carbon fiber roof and no adjustable suspension. so its probably the lightest version of the car there is. We will be taking the car to the scale to see. What we're missing is an M4 with carbon fiber roof and M suspension (if you have one , please take it to any truck stop and get it weighed for $7-13 and PM me)

3. He is 280 lbs and ran 11.83... he let his friend 100lb girl drive and she ran the 11.68 . The car really drives itself once you figure it out and follow my directions and you can teach this to the lightest driver you can find and set some records.

For full info , click this thread
http://f80.bimmerpost.com/forums/sho....php?t=1090482

[AlpineE92M3]

Wow 11.6 on a stock M4. That is damn impressive!

[CanAutM3]

Originally Posted by xxx_mina

2.He has the M4 with carbon fiber roof and no adjustable suspension. so its probably the lightest version of the car there is. We will be taking the car to the scale to see. What we're missing is an M4 with carbon fiber roof and M suspension (if you have one , please take it to any truck stop and get it weighed for $7-13 and PM me)

If it has DCT, it is not the lightest M4 around. DCT weighs 89lb more than 6MT .

Originally Posted by xxx_mina

3. He is 280 lbs and ran 11.83... he let his friend 100lb girl drive and she ran the 11.68 . The car really drives itself once you figure it out and follow my directions and you can teach this to the lightest driver you can find and set some records.

For full info , click this thread
http://f80.bimmerpost.com/forums/sho....php?t=1090482

So the wifey beat the hubby How did he take it ?

Thanks for posting the link. That time and especially that trap speed are very impressive. As you stated, I don't think I have seen another stock M4 that was that fast.

Your car is also quite impressive

[xxx_mina]

Originally Posted by CanAutM3

If it has DCT, it is not the lightest M4 around. DCT weighs 89lb more than 6MT .



So the wifey beat the hubby How did he take it ?

Thanks for posting the link. That time and especially that trap speed are very impressive. As you stated, I don't think I have seen another stock M4 that was that fast.

Your car is also quite impressive

Lol - The 6MT will be the lightest and will put down the most power, However i doubt its gonna run the fastest time. Nothing launches as good as this DCT and shifts as fast...

Mina

[CanAutM3]

Originally Posted by xxx_mina

Lol - The 6MT will be the lightest and will put down the most power, However i doubt its gonna run the fastest time. Nothing launches as good as this DCT and shifts as fast...

Mina

Agreed

[blwbyuii]

Mina,
Thank you for the write-up I was trying to figure it by trial and error before I read your explanation.

[SflBimmer8484]

Good info. Thanks for sharing

[xxx_mina]

Originally Posted by blwbyuii

Mina,
Thank you for the write-up I was trying to figure it by trial and error before I read your explanation.

You guys are all welcome. Between me and eazrad we pretty much tried every possible launch to see how effective it is on both the street and the track. There is still a little more to try out but this is the best we can figure out using stock tires. Once we put drag radials on, its probably gonna be a whole new game.

[TurboSid]

Originally Posted by xxx_mina

No i dont, if you warm up your tires like i reccomended and dont spin in first, you most likely wont spin in 2nd... maybe a chirp... on the track you should'nt at all . I could be wrong , you might need to limit boost in 2nd...but the way the car shifts into 2nd early on its own might also be the reason i dont spin in 2nd. your probably riding first out and shifting into 2nd higher in the power band. Try it, play around with it and see...

I will play around with it. I'm talking more about daily driving though not just track. Do you use the same setup on the streets or do you adjust?

[xxx_mina]

Originally Posted by TurboSid

I will play around with it. I'm talking more about daily driving though not just track. Do you use the same setup on the streets or do you adjust?

i've used same exact technique on the track and on the street and its worked on both ... map 6 on the track, map 2 on the street... both with 6psi boost limit in first no limit in 2nd. you have to really warm up your tire and increase the boost limit if your still spinning.

[harry$]

What kind of 60ft can one expect on a non prepped surface with street tires and drag radials?

[xxx_mina]

Originally Posted by harry$

What kind of 60ft can one expect on a non prepped surface with street tires and drag radials?

we'll ship me some drag radials and a v-box to measure my 60ft and i will find out for you

Actually just a V-Box or any sort of device to measure my 60ft and i'll tell you. I'm shopping for Rims and Drag Radials right now....

[harry$]

Originally Posted by xxx_mina

we'll ship me some drag radials and a v-box to measure my 60ft and i will find out for you

Actually just a V-Box or any sort of device to measure my 60ft and i'll tell you. I'm shopping for Rims and Drag Radials right now....

Might as well just add that V-Box to your shopping list while you are at it!!

[Longbow64]

Does the car remember the RPM setting or is this something that has to be set again if you shut down the car?

[Mike@N54Tuning.com]

Thanks for posting this write up. Was very informative.

Mike

[TurboSid]

Originally Posted by Longbow64

Does the car remember the RPM setting or is this something that has to be set again if you shut down the car?

For me it has always reset to 3k and had to manually drop it each time LC is enabled (Even with the car remaining on)

[Longbow64]

Well that's not very useful