Page 1 of 4 1234 LastLast
Results 1 to 25 of 97

Thread: BMW turbo street car Drag Racing 101

  1. #1
    Join Date
    Dec 2002
    Location
    Sydney, Australia
    Posts
    8,867
    My Cars
    1999 BMW M Coupe

    BMW turbo street car Drag Racing 101

    Kenny's ideas on drag racing a BMW turbo street car.

    I've assumed the following:

    + BMW turbo street car (not street/strip cars)
    + Street radial tyres with street rims (no front runners, etc)
    + Pump fuel
    + Manual transmission

    Setup For Drag Racing - Weight Reduction
    First setup you car before going to the strip.

    Your first task is weight reduction. Ensure you get to the strip with 1/8th tank of gas. That means allowing enough gas to get there with 1/8th left. Better to arrive with too little gas and then topping it up a tad from your gas can, which is of course filled with the same unleaded gas you have in your tank. A properly mixed slug of octane booster (or unleaded race gas) will give you some peace of mind too. Remember to put the booster in first to allow the gas to mix with it properly in the tank.

    Every quart of fuel weighs 1.5 lbs.

    Next drain all the water out of your washer botle. My M Coupe takes 5 litres in the washer bottle which is 11 lbs you don't need.

    Then remove the spare tyre, toolkits and anything else from your trunk and from inside your car. Anything that can be eaily removed should go (CD Stackers, carpets, lose stuff, etc).

    Now decide if you want to go to the trouble of removing your rear seats and passenger seat. Believe me when I tell you it will make a big difference. On average they say every 100 lbs is a tenth (0.1 off your ET).


    Setup At The Strip - Tire Pressures
    Now you've driven to the strip and been through scrutineering, get out your trusty pass journal and tire pressure gauge.

    Ensure you've got 1/8th tank of gas - you don't want to starve for gas during a pass. Now hook up your compressor and increase your front tires to 55 psi. If you don't have access to a compressor then swing by the closest place to your drag strip and do this before you arrive at the strip.

    You increase the pressure in your front tires to minimise rolling resistance. If you happened to have an alternate set of narrower wheels/tires then you'd fit the narrowest practical set for race day.

    The rear tire pressure is more involved, because you've got to try a range of pressures and see what results in the best 60' times. The optimum setting changes as the weather conditions change, so this is a bit of a black art. That's what your Pass Journal is all about. This is where you record your car setup and the results after each run. That way you can make changes one at a time and make some sort of analysis in order to optimise your setup.

    Generally speaking you should drop your rear tire pressure 4 psi from standard and then work your way down by half a psi at a time until your 60' times get worse.

    Remember that fine adjustments on street radials is less of a factor than when you graduate to drag radials or slicks. However it is still well worth your while to get close to the optimium.

    Your Pass Journal will have an entry for every pass you do, including the following information as a minimum:

    + Tire pressure
    + Launch RPM
    + 60' result
    + My comments

    More on how to use your Pass Journal seek the optimum setup in a later post.


    The Burnout - How Long?
    If you are a beginner or feel a bit nervous about the upcoming pass, then simply drive around or through the water box and don't worry about a burnout. You can add the burnout to your later passes as you become more comfortable.

    Remember that street cars using street radials are very different to a Top Doorslammer. You're not going to do a half track burnout and wow the crowd. Street cars that do long pointless burnouts are basically wasting everyone's time. Don't be one of them!

    Now street radials like a touch of heat in them to get optimum traction. But too much heat and their traction is reduced. However if you don't spin the tires at all then you've still got some water and grit on your tires from the water box (unless you managed to drive around it).

    My advice for street radials is to drive through the water box and come to a halt. When signalled by the official, dial up the revs and drop the clutch. Wait until your tires smoke a tad and then button off. We're talking less than a 2 second burnout here. More than that and you risk cooking the rubber (ie reducing traction until they cool).

    Realise that drag radials and slicks are made totally differently to street radials. These special tires require a lot more heat to work. Street radials don't.


    The Burnout - How To Do One?
    Now you know how long to let the burnout go for, exactly how do you perform a decent burnout?

    Let's start from standstill, waiting for the official to motion you to start your burnout. Select the appropriate gear (1st, 2nd or 3rd depending on your horsepower, the higher the gear the more power required to turn the tyres over). When the official signals to start your burnout, dial in some revs and drop the clutch. You can dance your left foot over to touch the brake a tad and balance the revs via throttle with forward movement via brake (takes a bit of practice).

    Now if you continue to creep forward and start to contact your tires with dry sticky track then you're obviously going to put more strain on your driveline.

    When you've got some heat into the tires, just let off the brake and /or drop revs a tad and your car will creep forward. Get off the gas and allow the car to roll gently towards the staging lights.


    How To Pre-Stage
    You're rolling gently towards the staging lights. Keep your eyes on the Christmas Tree and look for the White Pre-Stage light to blink on. The instant you see this light come on you nail the brakes and come to a total halt. You're not yet fully staged - just pre-staged. The second Full Stage light is still unlit.

    I recommend you now wait until your opponent is at least Pre-Staged or even on Full Stage before you bump in to Full Stage. Once either competitor is on Full Stage, the other racer has only 20 seconds to fully stage or the starter may disqualify you. In practice at a street meet the starter will rarely disqualify you, but they may come over and bang on your side window to hint that you're holding things up!

    Once you are pre-staged you must now focus on that Full Stage light with all your concentration. Because as soon as you fully stage, the starter can trigger the Christmas Tree at any time.


    How To Bump On To Full Stage
    You're at a halt with the Pre-Stage light up and your competitor is fully staged.

    Now apply your ebrake gently and dial up your pre-determined launch RPMs. You've already thought about what RPM you're going to launch at before you lined up. If this is your first pass, then just choose whatever starting point you think appropriate.

    Your clutch is in, your RPMs are steady at your launch point and your ebrake is slightly on. Now you ever so gently tease your clutch out - looking for the friction point where the RPMs start to dip showing you the clutch is dragging your engine just slightly.

    With your hand you are holding the ebrake just slightly on. This is a delicate balancing act, ensuring your engine is at launch RPMs, your car rolls forward ever so slightly and your rear brakes are just slightly on to ensure you move very very slowly on to Full Stage.

    This is called bumping on to Full Stage and is not easy to do. If you roll forward too far you will Redlight by crossing over the start beam. No big deal, it's all practice and you'll do better next time.

    Once you bump on to Full Stage you pull your ebrake up firm so your car comes to a dead stop. But you don't allow the ebrake to ratchet on lock, you keep it on but not locked by pressing the button as you hold it.

    If you get it right you will find yourself fully staged, motionless on the start line and most importantly, you are solidly locked on your launch RPMs with your clutch just at friction point, dragging against your ebrake.

    You are not looking at your tacho to check your RPMs. You are not looking at your ebrake. You are not looking at anything other than the Christmas tree.


    The Launch
    It's been covered in detail in many other places so I'll just state it here. Because of human reaction time and because of the vehicle reaction time of your car's suspension and drivetrain, you do not launch when you see the Green light on the Christmas Tree. You launch the instant you see the last of the three Amber lights come on.

    Option One
    You're at steady launch RPMs with the clutch at friction point and the ebrake held on but not locked. As you see the last Amber come on, you release the ebrake fully (holding the button in) and flatten the gas while modulating your drivetrain using your clutch. Because you're launching a turbo car you flatten the gas. On an NA car you wouldn't do that.

    Option Two
    You've got your ebrake held on but not locked. You pulse your gas pedal so your RPMS peak at redline and drop slightly but stay in the power band of your engine (revving your engine quite hard). As you see the last Amber come on, you release the ebrake fully (holding the button in) and flatten the gas while modulating your drivetrain using your clutch. This is your attempt to build some boost off the line. Negatives are it's harder to get a consistent launch. Up to you - maybe try it both ways and see what you prefer.

    Whichever option you choose this is not easy to do and takes many repetitions to get a good result. This is where it's all at - your reaction time versus your opponent and how well you can launch your car without wheelspinning.

    You must slip your clutch mercilessly to get an optimum launch. Sometimes you may find you have not let the clutch out fully before it is time to change up a gear. This is OK.

    Wheelspin on launch or upshift will cost you precious time. The optimum launch is at 10% wheelspin. This is very difficult to achieve and again comes only with much practice and experience. It's all good!

    Yes, you will punish your clutch. Yes, it will give off that awful smell of tortured components. Yes - it is the only way to optimise your launch.

    Clutches are consumables and are meant to be replaced. Regular drag racing will severely shorten the life of your clutch, but so what? You replace the clutch and go on your way. Just like tyres.

    Take a look at my Pass Journal below. More about that in part 2.
    Last edited by MrBlonde; 11-07-2010 at 04:38 AM.
    .-=[ Kenny ]=-. See the BFc Drag Racing Standings List for BMW street cars. Watch my drag racing movies on YouTube. Some info on
    BMW turbo street car Drag Racing 101

  2. #2
    Join Date
    Dec 2002
    Location
    Sydney, Australia
    Posts
    8,867
    My Cars
    1999 BMW M Coupe

    Drag racing 101 part 2.

    Getting A Better Time
    Your reaction time (RT) is all about how quickly you react on the start line. It does not factor into your ET at all. However the winner of each race is very much affected by the RT. So once you are comfortable with the process of doing the burnout, launching and shifting up through the gears I recommend you treat each pass like it's a race. The only way to get better is to practice like you race.

    Drag racing is all in the launch. Every tenth (0.1 second) reduction in your 60' time is .15 to .25 reduction in your ET.

    You can beat an opponent with a much more powerful car by getting a sharp RT and by getting a sweet launch.

    Using Your Pass Journal
    After each pass I recommend you drive back to the pits after collecting your timeslip. Get out of your car and get your Pass Journal out.

    Now note down the vital pieces of information about the pass:

    + Launch RPMs: (eg 4500 RPM)
    + Tire Pressure: (eg 28 psi)
    + 60' time: (eg 2.150 seconds)
    + My comments: (eg Car bogged down, need RPMs)

    Sometimes you can easily tell what you did wrong - too few RPMs on launch and you bog down. Too many RPMs and you get wheelspin or wheel hop.

    Sometimes you have to use your 60' times to help you work out what's going on.

    The important thing to remember is to only change one thing at a time. Otherwise you have no idea which of the changes you made created the different result, not to mention that the combination of changes hopelessly confuses things.

    I recommend you start with your launch RPMs and keep your tire pressure at your standard setting (ie what you run on the street).

    The rule of thumb is that you want to launch at your peak torque figure. Now this is not so easy to find, because as you launch your engine and drivetrain slow as the load comes on. So you have to launch at an RPM level higher than your engine's peak torque, so that as the load comes on then you are at your peak torque.

    In practice, pick a fairly low launch RPM .. say 2000 RPM, and then bump it up 500 RPM at a time. Keep doing this until you get hopeless wheelspin on the launch. Then drop the launch RPM down by 250 RPM and try again. You're doing a sort of chop sort by way of hitting on the optimum launch RPMs.

    And how are you evaluating what is a good launch? By examining your 60' times after each pass. You soon note that wheelspin or wheel hop means a shitty 60' time and that bogging down results in a shitty 60' time, too. But sometimes it all goes right and you get a stormer!

    Before too long you'll have a good idea of the RPM band your car best likes on that day. Remember that different weather conditions will change what your car wants, but it will only change so far.

    Let's say you finally settle on 3750 RPM as the best launch, the one at which you consistently get the best 60' times. Now it's time to fiddle with the tire pressures. So you dial in every pass at 3750 RPM and then you adjust your rear tire pressure down by 0.5 psi each pass until you again notice your 60' times get worse.

    You should notice that the 60' times improve for a while and then get worse again. In any circumstance, you don't want to go much below say 10-12 psi less than recommended; that can be dangerous.

    Once you've done this analysis you will have an optimum launch RPM and an optimum tire pressure for that day.

    Now you will find that the optimum tire pressure will allow you to launch at a higher RPM! So you start the trial and error analysis all over again. Of course, for each pass you pre-determine what the launch RPMs will be so there's no thinking on the start line. And you record all your results in your pass journal when you get back. A pass journal may sound fancy but I use the back of a scrap of paper usually (see attachement image in post above) - whatever you prefer.

    Also don't forget to factor in your improvement as a racer. Your first passes will be crappy compared to your most recently passes as you get the hang of it all.

    It's all good fun! And it doesn't matter if you've got the most powerful car in the world or a stocker, the thrill of drag racing is there for everyone.

    A good racer can beat an opponent with much less hardware at his or her disposal using the techniques listed above. And it doesn't matter if you win by an inch or a mile ... winning is winning ;-)

    Here is my formal Pass Journal loaded up into a spreadsheet for more detailed analysis (just using my daily driver as an example):
    Last edited by MrBlonde; 11-07-2010 at 04:38 AM.
    .-=[ Kenny ]=-. See the BFc Drag Racing Standings List for BMW street cars. Watch my drag racing movies on YouTube. Some info on
    BMW turbo street car Drag Racing 101

  3. #3
    Join Date
    Dec 2002
    Location
    Sydney, Australia
    Posts
    8,867
    My Cars
    1999 BMW M Coupe

    Best rubber fitment for BMW street cars with unmodified bodywork

    This is the place to document the largest (tallest and widest) rubber fitment for unmodified BMW street cars (for drag racing).

    BMW E36 M3 unmodified bodywork
    With 17" rim:
    • Mickey Thompson ET Street Radial part number 3743R -> 275/40 R17
      + Tread width 10.2" (Can fit on rims 8"-10")
      + 26.0" tall and 82" circumference
      + Sidewall width 11.0"
      + Credit: Kurt (ParadigmGuy)

    With 16" rim:
    • Mickey Thompson ET Street part number 3793 -> 26"x11.5"-16
      + Tread width 9.7" (Can fit on rims 9"-11")
      + 26.2" tall and 82" circumference
      + Sidewall width: 10.8"
      + Credit: Mike Radowski

    • Hoosier QuickTime Pro DOT part number 17430 -> 26"x9.5"x16"
      + Tread width ? (Can fit on rims 6"-8")
      + 26.1" tall and 82" circumference (VERY tight fit in wheel well)
      + Section width 10.0"
      + Credit: Ulysses (Card Counter)


    • Mickey Thompson ET Street Radial part number 3793R -> 255/50 R16
      + Tread width 9.7" (Can fit on rims 7"-9")
      + 26.0" tall and 82" circumference
      + Sidewall width: 10.5"
      + Credit: Dave, George (trthrrt489, ImportedCars)

    With 15" rim:
    • Mickey Thompson ET Street Radial part number 3752R -> 235/60 R15
      + Tread width 8.0" (Can fit on rims 7"-9")
      + 26.0" tall and 82" circumference (VERY tight fit in wheel well)
      + Sidewall width: 9.5"
      + Credit: Alan (morerevsm3)


    • Hoosier Drag Slicks part number 18110 -> 26.0"x8.0"-15
      +Tread width: 8.0"
      +Diameter: 26.1"
      +Circumference: 82"
      +Recommended rim: 7-8"
      +Section width: 9.7"
      + Credit: Dave (trthrrt489)

    BMW E37/8 M Coupe unmodified bodywork
    With 15" rim:
    • Mickey Thompson ET Drag part number 3053 -> 26"x10"-15
      + Tread width 9.6" (Can fit on rims 9"-11")
      + 26.0" tall and 82" circumference
      + Sidewall width: 11.6"
      + Credit: Kenny (MrBlonde)


    • BF Goodrich Comp TA Drag Radial part number no longer available but try 82648 -> 275/50 R15
      + Tread width 9.6" (Can fit on rims 8"-10")
      + 26.1" tall
      + Section width: 11.3"
      + Credit: Kenny (MrBlonde)

    BMW E30 unmodified bodywork
    With 14" rim:
    • Mickey Thompson ET Drag part number 3013 -> 24.5"x8"-14
      + Tread width 7.7" (Can fit on rims 6"-8")
      + 24.5" tall and 77" circumference
      + Sidewall width: 9.9"
      + Credit: Donovan (BMW sob)

    BMW E46 M3 unmodified bodywork
    With 16" rim:
    • Mickey Thompson ET Street part number 3792 -> 26x10.50-16
      + Sidewall width: 10.3"
      + Tread width: 8.4"
      + Height: 25.9"
      + Credit: Adam (PEI330i)

    With 18" rim:
    • BF Goodrich g-Force T/A Drag Radial part number 89451 -> 275/35 R18
      + Tread width ?" (Can fit on rims 9"-11")
      + 25.6" tall and ?" circumference
      + Sidewall width: ?"
      + Section width: 10.9"
      + Credit: Vik (TaZaM3)

    BMW E90 335 unmodified bodywork
    With 17" rim: (APEX ARC-8 17"x9.5" ET 35)
    • Hoosier part number 18157 -> 28.0"x10.0"x17"
      + Sidewall width: 11.3" (fit rim 8"-10")
      + Tread width: 9.5"
      + Height: 28.0"
      + Credit: APEX (paintpro21)
    Last edited by MrBlonde; 06-06-2012 at 12:17 AM. Reason: Add 26x11.5-16
    .-=[ Kenny ]=-. See the BFc Drag Racing Standings List for BMW street cars. Watch my drag racing movies on YouTube. Some info on
    BMW turbo street car Drag Racing 101

  4. #4
    Join Date
    Jan 2002
    Location
    Atlanta, GA
    Posts
    1,092
    My Cars
    2011 CC 2.0t, 98 M3
    Kenny:

    LEt me just say thanks for this awesome info! Information like this is what many stick around here for...
    __________
    98 M3
    2008 G35S

  5. #5
    Join Date
    Feb 2006
    Location
    West Covina, California
    Posts
    2,393
    My Cars
    99 M3 *Turbo*, 56 VW 2.2L
    wow, thank for taking the time to write this up!
    CP Pistons
    Eagle Rods
    T67 Turbo
    Lots and lots of custom goodies and 666 fab schtuuufff



    05/01/07 RIP pops

  6. #6
    Join Date
    Jul 2004
    Location
    Edmonton
    Posts
    2,348
    My Cars
    t67 328is - KIA
    nice writeup
    M52 Power! 500whp?, ? ft/lbs
    Mods:8.5:1 CP pistons, Eagle rods, S52 cams, M50 intake manifold, Eurosport High Performance underdrive pullies, 3.23 lsd, ZKW's w. DDE, BBS RC's 18x8.5, Bilstein sport shocks, H&R sport springs, Eibach sway bars, BMW Motorsports x-brace, pwr 57mm rad, stewart high performance water pump, 6000k prolumen hid's, m tech kit

    custom turbo: sias tuning tec3, t67 ho, spa turbo manifold, 24x12x3 ebay intercooler, 750 cc low impedence injectors, arp head studs, walbro 255 fuel pump, aeromotive fuel pressure regulator, hks ezII evc, tial 50mm bov, tial 40mm wastegate, plx m250 wideband o2, cartech motor mount, turbowerx oil scavenge pump, spa gauges

  7. #7
    Join Date
    Feb 2002
    Location
    Aberdeen, MD
    Posts
    8,496
    My Cars
    Turbo 97 E36 M3
    excellent!!!
    1997 Arctic Silver M3
    CES Stage IV (651rwhp/615rwtq @ 24 psi)

  8. #8
    Join Date
    Apr 2004
    Location
    NOVA
    Posts
    2,333
    My Cars
    '99 M3
    very cool info, especially since i plan on going to the drag strip for the first time this year

  9. #9
    Join Date
    Dec 2001
    Location
    Holland MI
    Posts
    191
    My Cars
    N20-S/C 95 332is
    Great stuff Kenny.....Thank you.......

  10. #10
    Join Date
    Dec 2005
    Location
    Newport Beach, CA
    Posts
    541
    My Cars
    1989 BMW 325i, 2003
    Wow thank you so much Kenny! I'm planning to start drag racing for the first time next Fall and this is really helpful! thanks!

  11. #11
    Join Date
    Apr 2006
    Location
    San Francisco CA
    Posts
    548
    My Cars
    M3 Avus Blau
    Thx for the writeup

  12. #12
    Join Date
    Sep 2004
    Location
    calvert county Md.
    Posts
    4,359
    My Cars
    328i turbo
    Quote Originally Posted by MrBlonde View Post
    This is the place to document the largest (tallest and widest) rubber fitment for unmodified BMW street cars (for drag racing).

    BMW E36 M3 unmodified bodywork

    With 16" rim:

    Hoosier QuickTime Pro DOT part number 17430 -> 26"x9.5"x16"
    + Tread width ? (Can fit on rims 6"-8")
    + 26.1" tall and 82" circumference (VERY tight fit in wheel well)
    + Section width 10.0"
    + Credit: Drew (//M3 Crazy)
    Quote Originally Posted by ///M3 CRAZY View Post
    oh and to be clear i cannot take full credit for this fitment!!!! i got the idea from CardCounter who did this fitment on his stock 16 inch 328 sport wheels first. i was the first to try with the slightly wider and lower offset contour reps but the general fitment was done by CC......

    Great job Kenny!!!
    The only thing I keep trying to do is keep a log. I kept trying last year and had a few notes from some runs.
    Last edited by card counter; 04-07-2007 at 12:55 AM.
    996WHP 2.8 and going nowhere fast
    . e36 4Dr with A/C and leather seats in U.S.
    www.bmwturbo328.com 9.93@152.6

  13. #13
    Join Date
    May 2004
    Location
    San Diego
    Posts
    9,714
    My Cars
    '97 M3/4 - black/bla
    Thanks Kenny, appreciate it.
    Kurt for Congress in 2020


  14. #14
    Join Date
    Sep 2004
    Location
    NC
    Posts
    1,608
    My Cars
    e36 m3, e39 m5
    very nice writeup!
    11.75 @ 131 6262 2.8l e36 m3 - 2011.

  15. #15
    Join Date
    May 2004
    Location
    Queen Mary's Land (MD)
    Posts
    5,328
    My Cars
    01 530i Sprt Pkg, 96 328
    That's great stuff, thanks!!!
    ~Phil
    Madeiraviolett Bf.C club member #001

    1996 BMW 328is Madeiraviolett/Dove Grey: 5 Spd, Sport, Cold Weather & Premium Sound pkgs.
    3.5" ECIS/ITG intake -> Samco ASC Delete Boot -> M50 Manifold -> S52 Cams. AA software, Dynomax Cats & Stromung exhaust
    UUC Pulleys & Clutch stop, FDM=Zionsville radiator w/ SAMCO hoses, Fidanza LTW flywheel & M3 clutch, UUC Evo3 SSK, 3.23 LSD
    H&R Springs w/ Billstein sport shocks/struts, PUR RSM's & RTAB's, CF Strut brace, UUC Swaybarbarians, Motorsport X-Brace, 18x8.5 M-Classics
    Power Slots/Carbon Metallic Pads, Hella CELIS projectors + 5k TRS HID's, Fog delete=Brake cooling duct, LTW wing, ///M Bumper & R. Diffuser
    CCA Member #382557 FS: E36 Sport Pkg Sway Bars & OEM OBD2 dual catback muffler (great for 323 folks)[/SIZE]

  16. #16
    Join Date
    Oct 2003
    Location
    Austin, TX
    Posts
    440
    My Cars
    '97 M3 Sedan
    There might be some M/T's in my future assuming my motor's not toast!

  17. #17
    Join Date
    Apr 2004
    Location
    Wpg/Canada, Garmisch/Ger
    Posts
    5,392
    My Cars
    '01 Mcoupe / '16 Golf R
    a very very valuable contribution to this forum, bimmerforums thanks you for this!!!

  18. #18
    Join Date
    Nov 2005
    Location
    Linden, NJ
    Posts
    4,065
    My Cars
    97 M3T, 02 M3T, 89 E30
    I had ~50 timeslips saved in my laptop bag with notes but some asshat decided to break into my car last year and steal everything.
    97 M3 - 8.94@164.33 - 8 sec street machine, all BMW driveline, factory ECU
    02 M3 - 9.74@145.99 - Maximum PSI stage 2 turbo kit, stock motor, factory ECU
    16 M3 - 9.47@149.22 - MaxPSI downpipes/exhaust/intakes, HCP/MaxPSI flash, Pure turbos, Dodson clutches, EOS intake/intercooler
    BMW SOB's turbo E30 - 8.72@158.39
    follow our latest builds and upcoming events! - facebook.com/maximumpsi - instagram.com/maximumpsi

  19. #19
    Join Date
    May 2004
    Location
    San Diego
    Posts
    9,714
    My Cars
    '97 M3/4 - black/bla
    Quote Originally Posted by aespen View Post
    There might be some M/T's in my future assuming my motor's not toast!
    Come up to Temple on Thursday. I'm planning on going with my MT's.
    Kurt for Congress in 2020


  20. #20
    Join Date
    Jan 2004
    Location
    Orange County, CA
    Posts
    1,865
    My Cars
    BRG M3
    Thanks for taking the time to provide such a comprehensive write-up. It's nice coming from someone that is experienced and familiar with our cars. Goodtimes.
    3.2 obd1 kenobi | built head | tubi exhaust | koni race coil-overs | gc race plates | ma shaw ltw wing | rieger ltw splitter | oem bmw roof rack | oem recaro gt3's | BBS RS...

  21. #21
    Join Date
    Dec 2002
    Location
    Sydney, Australia
    Posts
    8,867
    My Cars
    1999 BMW M Coupe

    Drag Racing 102: Advanced techniques

    Kenny's ideas on drag racing a BMW turbo street/strip car.

    I've assumed the following:

    + BMW turbo street/strip car (not racecar)
    + Drag Radials or Drag Slicks
    + Racing fuel (like C16)
    + Manual transmission
    + Line locker
    + Racing clutch
    + Boost controller

    Setup At The Strip - Tyre Pressures
    Set the pressure in your front runners to the maximum allowable (say 55 psi). Then forget them.

    Cars over 3000 lbs are considered a heavy car by drag racing standards. There are special slick compounds for cars over 3000 lbs (most of us).

    I'd recommend starting with 18 psi and varying to see what gets you the best short time.

    Remember small slicks need more air in them, especially with high power sedans.


    The Burnout - How Long?
    Drag Radials (eg Mickey Thompson ET Street) require two hard burnouts to get up to heat. After tha a quick burnout before each pass.

    Drag Slicks require one hard burnout at the start of the night, followed by a light burnout each time.

    For a hard burnout wait until you can see the rubber hazing and then button off.


    The Burnout - How To Do One?
    Select 3rd gear with your rubber in the waterbox. Now pump up your brakes and activate your line locker (if you have a brake pressure guage you're aiming for 2000 psi).

    If you are running a twostep activate it now in burnout mode.

    Fully press the gas pedal down and wait until you hit the two step, then step off the clutch while keeping the line locker activated.

    When you see the rubber hazing, deactivate the line locker and allow the RPMs to drop, then button off.

    Stage immedaitely while the rubber is sticky.


    How To Bump On To Full Stage
    Creep into Pre-Stage. Pump up your brakes to about 300-400 psi on the brake pressure gauge. Activate your line locker.

    If you are running a two step activate it now in launch mode. If you're running antilag activate it now.

    With the line locker on, dial up some RPMs and slip the clutch out a little so the car is pulling against the brakes. This way you can very precisely bump in to full stage.

    Once in full stage clutch in and floor the gas pedal. You are now bouncing off your twostep limit and antilag is popping away nicely.

    The Launch
    When you see the last amber light drop the line locker and step off the clutch in one motion. Start shifting fast!

    At the Stripe
    Stay into it for one-one-thousand-two-one-thousand after you think you've crossed the stripe. That's to make sure you actually have crossed the finish line before you button off.

    Stay into the gas as you trip your parachute and wait until it's deployed, then button off and slip your tranimission into neutral. Let the 'chute kill most of your speed and then ease on the brakes slowly and gently.

    If You Break
    If something lets go then it's usually at the start line. Immediately drive off the race line towards the sidewall and stop as quickly as possible. That reduces the cleanup time for the track officials if you're dropping any fluids onto the race surface. They will like you a lot more if you remember to do this.

    If the Car Gets Loose
    Nobody ever crashed by buttoning off.
    .-=[ Kenny ]=-. See the BFc Drag Racing Standings List for BMW street cars. Watch my drag racing movies on YouTube. Some info on
    BMW turbo street car Drag Racing 101

  22. #22
    Join Date
    Dec 2006
    Location
    orygun
    Posts
    1,045
    My Cars
    2008 GTI, 2010 Mazda3
    great read. Thank you Mr.Blonde

  23. #23
    Join Date
    Sep 2004
    Location
    calvert county Md.
    Posts
    4,359
    My Cars
    328i turbo
    Quote Originally Posted by MrBlonde View Post
    If You Break
    If something lets go then it's usually at the start line. Immediately drive off the race line towards the sidewall and stop as quickly as possible. That reduces the cleanup time for the track officials if you're dropping any fluids onto the race surface. They will like you a lot more if you remember to do this.
    .
    Excatly.. Im a pro at this one
    996WHP 2.8 and going nowhere fast
    . e36 4Dr with A/C and leather seats in U.S.
    www.bmwturbo328.com 9.93@152.6

  24. #24
    Join Date
    Jan 2006
    Location
    Mechanicsburg, PA
    Posts
    4,567
    My Cars
    yes
    Excellent job Kenny.

    Thanks,
    Don

  25. #25
    Join Date
    Aug 2003
    Location
    San Diego,CA,USA
    Posts
    24,275
    My Cars
    1997 Turbo M3 Coupe

    Thank you Kenny!

    Absolutely amazing write-up! Much appreciated! I will use these techniques exact to your book as soon as my car is available to do so.
    Where have I been? Astral projecting.

    Quote Originally Posted by jszy25 View Post
    Get drunk with Mike Radowski they said, it'll be fun they said...A broken toe, the worst hangover known to man, and bite marks in my arm said otherwise

Page 1 of 4 1234 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •