help please- taming little bavarian wild child

Discussion in 'GT4 Tuning' started by nomis3613, Jul 31, 2010.

  1. nomis3613

    nomis3613 Premium

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    Hi, I thought I'd challenge myself by seeing how I could set up a BMW 2002 Turbo with 350kW to run at Deep Forest. But I've bitten off more than I can chew! I've tried every trick I know, but it remains a darty little beast which drifts and snaps without warning. So if people could have a look at my setup and suggest settings to make it more controllable without changing any parts, that would be great thanks.

    PARTS:
    racing exhaust, chip, turbo stage 3, large intercooler, port polish, balancing (350kW)
    sports medium tyres
    racing brakes, BBC
    FC suspension, FC gearbox, triple clutch, racing flywheel, lightened driveshaft
    full LSD, stage 3 weight, stiffness enhance

    SETTINGS:
    BBC 13 / 18

    springs 3.6 / 3.6
    height 180 / 180
    damper bound 8 / 2
    damper rebound 10 / 2
    camber 1.5 / 1.5
    toe -2 / 4
    stabiliser 5 / 1

    gears 3.75 / 2.62 / 2.16 / 1.74 / 1.43 / 1.15 (set with FD = 2.5, auto =11), FD 2.8
    LSD 30 / 20 / 40

    COMMENTS:
    My challenge was to stuff the little BMW with 350kW and get it to handle nicely on Sports Medium tyres without downforce. Of course, the handling could be easily fixed with more rubber or aero, but that would be too easy!

    I found the rear brake could be increased to 24 without locking, but I reduced it to get some entry understeer. If a suspension setting can reduce it's twitchyness then I'd like to return the rear brake to 24.

    The rest of the suspension is a bit of a mess, I tried everything to make it understeer with little success, in the end the main improvement was LSD decel. The -ve front toe was deliberately used to reduce turn-in, that's how desparate I was! My best lap was 1:23.2 (but I'm not a very good driver, I'm sure quicker is possible).
     
  2. Greycap

    Greycap Premium

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    [​IMG]

    Nothing more to be said. Admittedly that tune has Sports Softs but they don't change the general behaviour at all, just the level of grip. But you'll find that there's no point in trying to make this car understeer as it'll only make it slow - you're better off with adapting your driving to it.
     
  3. nomis3613

    nomis3613 Premium

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    Thanks, I'll try out these settings. Both of Leonidae's photos show the 2002 totally sideways, I'm a bit worried that this is a warning!!

    Do you know which track the tune was set up for (also so I can see how close I can get to the 1:59.369 time in the banner)?
     
  4. Greycap

    Greycap Premium

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    It IS a bit drifty but that's its natural behaviour. It won't snap on you but it likes to slide. The tune wasn't made for any specific track that I know of, we try to make all round setups, but I drove that time at Grand Valley forward.
     
  5. niky

    niky Moderator

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    +1... it's an intoxicating challenge... like an old Porsche. With the suspension controls inherent in GT4, it's hard to make it more stable without making it slower. One of my favorite cars in the game.
     
  6. sukerkin

    sukerkin

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    Oh how you tempt me to come out of LOTRO for long enough to try and sort this car out. I always meant to have a look at it but never did - I do recall driving it but I think that was for one of the 'set piece' challenges in the game {a license test maybe?}.
     
  7. nomis3613

    nomis3613 Premium

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    Amen, the MFT tune made it more controllable, but I reckon there is very little difference in the overall balance.

    Just wondering, theoretically what could you do to make it less slidy (without aero or better tyres)? Of all the differences between my initial tune and MFT, the suspension had the most effect but nothing I've done has changed the balance very much.

    Incidentally, the MFT tune has rear toe of -4. Do you think this is a typo perhaps? Sure, the setting has little effect in the 2002 but still I'm wondering why you would run rear toe-out on an already unstable car.


    Go on, do it!!! It's certainly a car to keep you on your toes.
     
  8. Parnelli Bone

    Parnelli Bone Premium

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    I would lower it, nomis. Alot. Put it back to its original height (120 mm) but then lower the rear further by 10 mm or 15 mm so. The brakes are too strong, I'd place both settings medium-ish. And oh goodness get rid of all that toe. Some toe is okay, but you've got alot! The rear stabilizer is too weak, causing the rear to sway to and fro (especially since the entire car is set to 180 mm, there's a high center of gravity). Not sure what I'd do with the springs and dampers. I'm at work so I can't experiment, obviously.

    With all those settings, you may or may not still need a limited-slip.

    I actually wanna try "your" car, though, nomis. I've never been able to get a 2002 super-drifty (only mildly so). I've driven the MFT car before, but it was a long time ago.

    So maybe it's time to compare my car to your car to their car. :dopey:
     
    Last edited: Aug 2, 2010
  9. Leonidae@MFT

    Leonidae@MFT Premium

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    That is also a pretty old tune already, nowadays I use way more mild settings.

    *looks at the RUF BTR Evolution* well, then there are the exceptions that simply will never be tame..
     
  10. Greycap

    Greycap Premium

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    That car isn't even hair raising, I drove it again today. The banner lap time came down by a second and the lap involved just about no sliding at all - it just needs a calm hand to guide it in the corners instead of throwing around.
     
  11. niky

    niky Moderator

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    Pretty much like a 911. Tease the balance about rather than throwing it into a corner like you can a modern car.
     
  12. nomis3613

    nomis3613 Premium

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    Hey Parnelli, I'd be really keen to hear how the 3 different tunes feel to you.

    You were spot on about the rear stabiliser! Turns out stiffening it reduces oversteer, as if the car was RR. Strange! Yeah, and the toe was just making it wander at high speed, without any noticeable benefit. To me it seems that this car is very unusual to tune.

    Well, you guys must be far better drivers than me. I'm struggling to hang on, takes a lot of laps to get a good run with nice clean lines. Please tell me you're using a proper wheel or something and that's why you're so much better than my Dual Shock 2 driving :dunce:

    Case in point: I was being silly about how much I could make it understeer. Max rear stabiliser, brakes strongly biased to front. Boooooring! Most of the character of the car had been destroyed. But then my lap time came in... and it was the fastest so far. Argh!
     
  13. Greycap

    Greycap Premium

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    A bit of both - I have five years of GT4 experience, three and a half of them with a Logitech wheel. One year with a DFP and then two and a half with a G25. 85 gold licences, 100% completed.

    But, here's how it's done. 720p resolution recommended.

     
  14. Too Old

    Too Old

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    Darn Greycap, you hurt my feelings every time you post one of these videos. I'm like Nomis, I can get a good lap, but it takes me a number of laps to do it. If that was my video that would be lap 12 or 13.
     
  15. Parnelli Bone

    Parnelli Bone Premium

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    Yea I plan on gettin to that today, after my weekly therapy session. :nervous:

    Wow. I've always found the 2002 easy to tune. It's a very easy-to-drive & tune vehicle in my opinion. But it seems you've selected settings that make it not handle like a Beemer anymore. Not that that's a bad thing. Like I said, I've never been able to get this car to be anything but compliant (nor have I really tried to make it non-compliant).

    Dual-shocks can keep up with wheels. I'm way better with a dual-shock than I am with a wheel, for instance.



    Yea, Greycap hurt my feelings, too. :( Those mad Finners....



    I'm...KIDDING!
     
  16. Parnelli Bone

    Parnelli Bone Premium

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    I let Bob do a few laps before taking over. I always like doing this for some reason.



    nomis's 2002


    It looks really tall! From a distance it looks like a Fiat or a Lada. Bet this car would make a good rally machine.

    Bob had no problem driving the car with a setting of "3". Tried bumping it up to "4" and he wiped out under the first bridge, though.

    ...now I drive...

    Wow, the gearbox is really busy! All 6 gears do come into play, though.

    And it is really slidey from the rear, too. You're right. Wow. Coming down the big hill, the car's rear gets really loose and just starts flopping around. Unbelievable! I believe it's very possible to attempt some drifts..Its's very easy to break the rear's traction...

    Yea, this is definitely one of the better drift cars I've ever driven, dude. I know you were trying to get it to understeer. But 90% of the time it wants to get all hooky from the rear.

    I'm not a pro at drifting, so the ones that I actually did accomplish were short and frantic, but the good thing is there is a safety margin where the car can be sideways yet front-end snap back can be avoided. :tup:

    Wow, those brakes are mooshy! Which is odd, I figured they'd be too strong. If I braked too late, but kept the car under control, there actually would be some understeer.



    Now my car


    I kept all of nomis's weight reductions and permanent engine mods for convenience, and I also kept the power exactly the same. I wanted to make this into a car I'd possibly drive during a sim race, though, so some of my part choices were rather mild.

    My aim was to get the 2002 handling more neutrally, so it's not really gonna be as fun as nomis's..but it'll be milder and more compliant (hopefully) Here's what I came up with:

    Tires: SM

    Brakes: racing kit installed
    Balancer: 18/12

    Suspension:

    Springs: 8.5 / 6.6
    Height: 123 / 108 mm
    B Damps: 4 / 2
    R Damps: 6 / 4
    Camber: 2.2 / 0.5
    Toe: 0 / -2
    Stablizers: 3 / 4

    Transmission: Default. 5th gear: 0.830, Auto: 20, Final: 3.350, no other changes.

    Clutch: sports
    Flywheel: stock
    Driveshaft: stock

    LSD: 20 / 50 / 5


    I wanted to keep the tranny stock (I like fixed transmissions if I can get away with using them) but in this case the 4-speed was too short. With those gears, the car is now effectively a 5-speed. 4th was too tall, but ah well. I'm not always after perfection when I tune.

    Notice the stock parts in the drivetrain. This car's got a very light rear, now that all that weight has been removed. Having ultra-light drivetrain parts isn't necessary because most of the engine's power will wind up getting wasted as wheelspin. My car DID still suffer from some wheelspin, though.

    My goal was to eliminate as much swipeyness as possible. I was successful at getting this car more controllable, but couldn't get there 100%. Not with this sort of power on those tires, anyways. So my car happened to get loose from the rear in 2nd gear, and would occasionally also get a little goofy in 3rd. There was nothing I could do further (settings-wise) about this, other than throttle-taming.

    But overall, this car is more controllable with mild understeer (assuming brake points are proper), mild to wild oversteer (driver's choice), but isn't as "fun" as nomis's ride.

    ..But like I said I couldn't get it handling 100% neutrally, not with that power and those tires. Now the....



    MFT BMW 2002 TTH '73


    Power is the same coincidentally, so no changes there.

    Wow. What a difference. wow wow wow.

    The car understeers heavily once it's mid-corner (there ya go, nomis), if braking points are missed by a hair. That's the first thing I noticed and I don't mean this in a highly critical way. We're supposed to have S3 tires on the car after all.

    The front-end grips-in if braking is correct, though, and feels about 80% reliable while doing so, but the other 20% there is a bit of light understeer still remaining.

    I couldn't brake into turns as late as I could in "my" car. Couldn't trail-brake as successfully. Not that this mattered much...

    Gearing is perfectly balanced. I expected nothing less from these guys. :)

    Wow. The rear-end is almost completely tamed. I figured the trunk (which is highly raised compared to the front) would be getting loose on me alot, but this is not so.

    Throttle must still be tamed in 2nd gear, but overall, the rear is more mashable than either my car or nomis's. I could give full throttle earlier and more successfully, and got the best lap times in the MFT mobile therefore.

    The rear-end would get lightly drifty on occasion, and this could be easily tamed with countersteer and/or throttle control.

    The MFT car felt the most confident thru turns 2 thru 5 (where the track weaves after it gets uphill). It could transition from side to side with the least drama and rear-end wheelspin.

    So far as actual drifts go, I couldn't manage them as easily in this one! The rear would start to get loose, I'd try to work the car sideways, but then the front-end would take over and SNAP1!! I'd be in the grass. :(

    After awhile, I did learn how to get my usual short-lived drifts here and there. No worries...this (I'm assuming) isn't supposed to be a pure drift car.

    I did try this car on S3 tires before calling it a day, which resulted in a more neutrally-handling car, but not an issue-free one.

    Understeer was halved, but there was still some remaining to watch for. And again, the rear could still get smokey with wheelspin, but (again) this was tamed even further.
     
    Last edited: Aug 4, 2010
  17. PF

    PF

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    I'd like to thank you all for bringing this car to my attention. It's ugly as a hat-full of arseholes but has that strange anti-beauty. Like Art-Deco architecture (or late Victorian for that matter). Like Dadaist poetry. Like bad goth poetry, it's a car accident that you just have to slow down for.

    I'll go and get it now and see how it rolls.
     
  18. Parnelli Bone

    Parnelli Bone Premium

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    :lol: Wow, that was deep!
     
  19. nomis3613

    nomis3613 Premium

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    Haha... I really enjoyed reading your description of trying to get a clean lap out of my unruly tune. Lots of LOLs!!

    Are you testing at Grand Valley or Deep Forest, by the way?

    To my thumbs (and I'm not saying my tune is better, or dissing the MFT tune in any way), it felt like MFT's didn't have much less oversteer than mine, it just felt a lot more controllable in doing so.

    I'm keen to try your settings, Parnelli, I'll give it a try in the next couple of days.
     
  20. Parnelli Bone

    Parnelli Bone Premium

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    That was Deep Forest.

    I'd agree. MFT's car had plenty of oversteer as well, but (as you noted) I could avoid it at will if I wanted to. I had more of a choice.