[j0hn08]

Wanted to share this with you guys. a month ago i went to Las Vegas Speedway 1/4 track and my best time was 13.5x @106mph w/ 91acn gas and was a little dissapointed because i wanted to break into high 12's with mods i have. Car mode was on sports+ DCT half off. Issue is with traction on lower gears that i just keep on spinning. Cant hook the car properly off the line .. Im still a newb driver since i dont really drive the car that much since i just work at home.

Before i went back to the track again last night. I kinda tuned the boost by gear settings in bootmod3 to see if i can improve traction on lower gears. Settings is below
1st- 50%
2nd- 50%
3rd- 30%

Went with my wife again last night and told her if i run 12's that i would take her to a steak place lol.. I am # 54 on timeslips

gas on car was on 91acn 12 gallons + 100oct 3 gallons equates to 93oct

1st run, i put the car in sports+ mode and hold DCT button to fully turn off traction control(i think this switches it back to comfort but with tight steering), left it on D so car will shift for me. didnt use launch control at all. no burnout. just floored it from get go. Time was 13.081 @ 107mph.

2nd run, same mode as first run but on manual and with launch control. Floored it again for the get go.. car spinned a little bit when i put it launch control mode. not sure why(you can see the tire slip from the video) before light tree turns green. quickly I release the gas pedal to stop the spin then quickly wot again when light turned green. Car finally hook correctly. 60ft 1.889. Time was 12.742 @ 106.45 even i got beat by the challenger!!


on 3rd and 4th run i lowered the tire pressure on the rear tires from 38 to 34PSI to see if i can still get a better traction. lol a mistake.. car wasnt hooking now like before. this is with launch control being used. Launches were terrible now back into 14's but thats ok since i even told my wife that i just wanted to get 1 12's and ill be done for the day.. I guess i would be keeping the tire pressure in the future around 37-39psi on the rears

Honestly, i just need to practice on my launches to be more consistent on times. There is still a lot of improvement that i can do i believe. I think this car is hard to make hook off the line. This is with Michelin PSS4 255/235/18.

For people that have good 60ft times . do you leave the car in sports+ with DCT half way off or hold down DCT as well to fully turn off traction completely? do you guys have any tips? what rpm? do you guys use launch control? how many psi on tires, etc......

Kinda contemplating still if xhp would be better to improve traction on lower gears + launch control settings vs just bootmod3 boost by gear settings.for $350 is it worth the shot? No budget yet for LSD

Just wanted to share with you guys

thank you again Mike @ xph and Cary(jordantuned) for all your help
Link of dyno vid https://f30.bimmerpost.com/forums/sh....php?t=1677709

Here is the link for the best run

Inside car 360 video

Bonus video - Messed up on the launch or launch control didnt activate properly but caught up at the end

[AmuroRay]

Nice information and data - but that still seems down on power.

Try lowering the tire PSI, and upping the boost by gear - you shouldn’t be cutting power by 2/3rd gear when most of that torque is already trailing off.

[n55david]

Originally Posted by AmuroRay

Nice information and data - but that still seems down on power.

Try lowering the tire PSI, and upping the boost by gear - you shouldn’t be cutting power by 2/3rd gear when most of that torque is already trailing off.

Hes not down on power. Hes killing power by reducing boost in multiple gears.

Also, lowering the psi isnt gonna do much if he has run flats. Since the tire is meant to run flat all he will be doing is hurting the integrity of the tire for if and when he does have a flat.

OP,

Dude, you need to just get different tires and learn to drive. Not knocking you, but you are whats holding your car back. you should be able to run a bit quicker at a higher mph Keep at it and youll get it!

[j0hn08]

Originally Posted by Phantom10R

Hes not down on power. Hes killing power by reducing boost in multiple gears.

Also, lowering the psi isnt gonna do much if he has run flats. Since the tire is meant to run flat all he will be doing is hurting the integrity of the tire for if and when he does have a flat.

OP,

Dude, you need to just get different tires and learn to drive. Not knocking you, but you are whats holding your car back. you should be able to run a bit quicker at a higher mph Keep at it and youll get it!

Tires are non flat Michellin PSS4.
No worries. hehe i know it is me that is holding it.. Just need more practice. thank you

[n55david]

Originally Posted by j0hn08

Tires are non flat Michellin PSS4.
No worries. hehe i know it is me that is holding it.. Just need more practice. thank you

gotcha. i wasnt paying attention.. manual or auto?

[j0hn08]

Originally Posted by Phantom10R

gotcha. i wasnt paying attention.. manual or auto?

Auto ZF8 transmission

[n55david]

Originally Posted by j0hn08

Auto ZF8 transmission

Try just a 10% reduction in first and go from there. a reduction in higher gears will be a waste

[thejeremyman9]

Did you not do a burnout on any of the runs? Was the track prepped? Asking because with warm PS4S on a clean dry road i can usually hook 1st from a dig with little to no spin.

I would recommend:

1. Only a little torque limit in 1st as mentioned above. No limit need in other gears. You should not spin 2nd at all.

2. Do a very brief burnout - just enough to clean the tires and get them a little warm. Make sure you roll out of the water still spinning - dont stop the burnout still in the water.

3.. To launch, apply medium brake force and when the light turns green floor the car and let off the brake about 0.5 second later - basically once the RPM builds to the stall of the converter. You do not want to actually hold the car back with the brake like with launch control, you only want to prevent the car from moving while you spin up the converter and start to spool the turbo. This is how i get the best launches on the street. You can try DSC fully off or just sport +

4. If you want the car to shift, at least make sure its in S, not D, for fastest shift times. You can also try short shifting at around 6k in manual mode. Not sure if it will actually be a faster time but power drops off quite a bit on stock turbo up top.

5. Report back with results

[AmuroRay]

Originally Posted by thejeremyman9

Did you not do a burnout on any of the runs? Was the track prepped? Asking because with warm PS4S on a clean dry road i can usually hook 1st from a dig with little to no spin.

I would recommend:

1. Only a little torque limit in 1st as mentioned above. No limit need in other gears. You should not spin 2nd at all.

2. Do a very brief burnout - just enough to clean the tires and get them a little warm. Make sure you roll out of the water still spinning - dont stop the burnout still in the water.

3.. To launch, apply medium brake force and when the light turns green floor the car and let off the brake about 0.5 second later - basically once the RPM builds to the stall of the converter. You do not want to actually hold the car back with the brake like with launch control, you only want to prevent the car from moving while you spin up the converter and start to spool the turbo. This is how i get the best launches on the street. You can try DSC fully off or just sport +

4. If you want the car to shift, at least make sure its in S, not D, for fastest shift times. You can also try short shifting at around 6k in manual mode. Not sure if it will actually be a faster time but power drops off quite a bit on stock turbo up top.

5. Report back with results

He’ll make more power by spinning the car out to approximately 6500-6700rpm.

[Hirads]

Get rid of those run flats.

[mike@x-ph.com]

Nice

[thejeremyman9]

Originally Posted by Hirads

Get rid of those run flats.

He already said specifically he has non-runflat PS4S...