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Thread: lifting front inside wheel on turns.

  1. #1
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    lifting front inside wheel on turns.

    Hi Cunts.
    Car is a s13 silvia.
    Lightly modified but very competitive in its current chosen format, Hillclimbs.

    I ran at legends of the lakes last weekend and the car went pretty well.
    Felt good. A little bit of oversteer on corner exit under power but it is a turbo car so expected.

    But after looking at photos after the event it cocks the inside front, not massively but enought that its off the ground in a couple of corners.
    Its setup as i would any of my turbo rwd circuit cars, but on the track they always seemed to corner pretty flat.

    Is this having a huge effect on times if its cocking a wheel?
    I know that four on the deck will corner faster than three in a circuit application but is it as critical on a bumpy hillclimb surface?

    Will i die?

    Cheers
    Originally Posted by Tut
    THEY SHOULD ANALYY RAPE THEMSELVES WITH A FUCING CACTUS UPSIDE DOWN WITH COCONIUTS AND PINEABPPLES AS CHRISTMAS BALLS THE FUCKNIG THIEVENG CUNTS ID RATHER DIE FROM HAVING A RAINBOW UNICORN URETHRALLY RAPE ME THAN TO FUCKNIG DO BUSINESS WITH THEM CUTNST EVER AGAN

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    I reckon it's as much the form of that uphill corner and a bit of powerdown squat. Do you reckon the spring is getting to full droop or is the swaybar holding it up a bit?

    The tyre in the air isn't slowing you down, indeed you are likely getting great weight transfer for traction & punch out of the corner......

    Having seen what else you've survived, this ain't gonna kill you.
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  3. #3
    *Italian Stallion* milo's Avatar
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    What are the Swaybar Sizes?
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    Suspension details?

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    Nothing wrong with inside front off the ground. Indeed, pretty much any old escort lives with the front off the ground. As above, softer rear spings/bar/roll stiffness is good to get power down out of slower corners, which is typical of hillclimbs in comparison to circuit racing corner speeds. Power down is king in a powerful rear drive car - you want to play to your strengths and that is to get the thing punching hard out of a tight corner with no more than a roll of the wrists into oversteer after the apex. It's all a compromise as ever...

  6. #6
    Arrogant wankeler Slides's Avatar
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    Yeah sounds right for hillclimb as long as tge front isn't washing out on the way into corners.

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    What are the Swaybar Sizes?
    Factory front. no rear.


    I guess its going to be a compromise.
    Hillclimbs are never going to be perfect flat nor always bumpy.
    It has quite a bit of pace and is easy to drive so perhaps ill just leave it for a bit, maybe play with bump and rebound a bit and keep on having fun.
    Originally Posted by Tut
    THEY SHOULD ANALYY RAPE THEMSELVES WITH A FUCING CACTUS UPSIDE DOWN WITH COCONIUTS AND PINEABPPLES AS CHRISTMAS BALLS THE FUCKNIG THIEVENG CUNTS ID RATHER DIE FROM HAVING A RAINBOW UNICORN URETHRALLY RAPE ME THAN TO FUCKNIG DO BUSINESS WITH THEM CUTNST EVER AGAN

  8. #8
    xxxx BoboTheMonkey's Avatar
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    just drive slower

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    Registered User adamRSLC's Avatar
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    My car does the same (VL) after i changed the valving in the rear shocks to allow more squat, combined with not a lot of droop on the front it picks the wheel up on power down out of slow corners. Works well, with a solid improvement in lap times.

    Adam
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    Back in the day, RX3's in particular seemed to drive everywhere on three wheels, and were still quick. It's not ideal, but it's more important that the car feels balanced on that track.

    You could dial it out by reducing front roll stiffness and increasing rear roll stiffness, and find the car goes slower because it oversteers more.

    Just check there's enough droop from static ride height too.

  11. #11
    Registered User irsa76's Avatar
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    Gibson Motorsport liked to have the rear of their Commodores pretty soft.

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    My old 911 did this at every corner. Stock suspension with front sway bar and semi slicks.
    Bigger torsion bars all round and better shocks made it handle properly.
    Soft setup is slow these days with good tyre technology.

    Click image for larger version. 

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  13. #13
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    Quote Originally Posted by mph View Post
    Soft setup is slow these days with good tyre technology.
    This flies against all that I've learnt and all I believe to be true.

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    My view of motorsport is that everything you do with a car comes down to it's attachment to the pavement. You can have all the power in the world, but you've still got to get it to the ground. How you use your tyres is how you beat your opposition. I still believe that the softest possible springing is going to work your tyres best.

    Disclaimer: Aero platforms need different attributes and clearly you want your center of gravity under control.
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    Itís all relative. Iím comparing to 40 years ago. Spring rates have tripled

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    It's true, car weights have doubled!
    " I didn't have $$$$$, so I thought I'd build a car instead" : Ron Tauranac

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    And tyres are much better.... anyway. You know exactly what I mean.

  17. #17
    Registered User gmx's Avatar
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    But are wheel rates still the same?

    There is some weirdness with MacPherson struts I cannot get my head around and tunas just recommend ridiculous spring rates or want a consulting fee.
    Soft spring, big bar up front?
    Or stiff spring, reasonable/standard bar front?

    I don't believe there's is perfection. I'm not suspension guru and flip flop regularly. If you're lifting a front wheel exiting a corner, I think that alludes to what Roy said; you're getting good workout from your rear end. Is it stable, snappy, grippy? If you try to "fix" the front, you might just end up penalising yourself in other areas of the corner and resisting load transfer to the rear.

    One odd behaviour I have seen in a lot of cars especially BMWs, Nissans, older (tracked) Supras is the front end skids and bounces across the surface when braking/turning in. Surely this is because of the retarded spring rate and dampers they're running?
    Last edited by gmx; 23-11-18 at 08:24 AM.

  18. #18
    Non Compos Mentos Gammaboy's Avatar
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    The big spring rates people recommend for strut frontends is just to try and get around the poor camber gain thats inherent in strut type suspension design.

    Soft spring, big bar will always ride better and work better on a rough surface for a given total roll stiffness.
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  19. #19
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    My 2c.

    Run the softest springs you can get away with.

    What that is will depend on a few factors, but ultimately the stop watch. You can spend your life tuning the car to feel good in one problem corner only to make it a little bit worse in several others more than negating the gains.

    Ideal setup can vary depending on the particular course. (And driver style/preference.. )

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    Quote Originally Posted by gmx View Post

    There is some weirdness with MacPherson struts I cannot get my head around and tunas just recommend ridiculous spring rates or want a consulting fee.
    The weirdness you speak of is the roll centre height going under ground when you lower the ride height excessively on a MacPherson strut. This causes more body roll, which the uninformed try to correct with stiffer springs and roll bars. Problem is, the higher spring rate and roll stiffness reduces mechanical grip. The better solution is to put the roll centre back to as close to factory as possible.

    FWIW, my philosophy on his subject is exactly the same as 36, run the softest springs and roll bars you can get away with, compensate for body roll with more negative camber, and use the stopwatch to guide you to the optimum setup.

  21. #21
    Registered User gmx's Avatar
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    Is there a true certain way to calculate that for a given chassis. Or wheel rate for a given sprung and unsprung corner mass?
    Going much more complex and OT.. I found this online calculator/form for E46s: http://www.fatcatmotorsports.com/FCM..._M3_Online.htm

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    The better method is to calculate or measure spring frequency. For a sedan with limited or no aero you want 1.5-2 Hz

  23. #23
    Registered User gmx's Avatar
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    That seals it for me. The "kit" I'm being pushed to would be 2.15hz which imo, is way too much regardless of good the damper is. Ty

  24. #24
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    You are welcome.

    I just stumbled upon this article, which is relevant to this thread:

    https://motoiq.com/how-to-make-crappy-cars-handle-well/

  25. #25
    Registered User gmx's Avatar
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    ^ good article. I actually read that a while ago. I'm not lowered, and probably not going to.

    bp, are you lowered?

    On the forums I'm seeing the same argument, "when lowered -> messes with roll centre". Well yeah this applies in compression during cornering for sure. But I'm not a stance cunt so what happens if I just stay with my superior German geometry ride height and travel? lol.

  26. #26
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    Quote Originally Posted by Sprinkles View Post
    Back in the day, RX3's in particular seemed to drive everywhere on three wheels, and were still quick. It's not ideal, but it's more important that the car feels balanced on that track.

    You could dial it out by reducing front roll stiffness and increasing rear roll stiffness, and find the car goes slower because it oversteers more.

    Just check there's enough droop from static ride height too.
    It was reckoned to be the best way when live axles were the standard gun set up. Lift the front to load the rear and maximise traction. With fancy diffs, IRS and sticky wider tyres that might not apply so much now, keep it flat and maximise all contact patches?

  27. #27
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    Quote Originally Posted by gmx View Post
    ^ good article. I actually read that a while ago. I'm not lowered, and probably not going to.

    bp, are you lowered?

    On the forums I'm seeing the same argument, "when lowered -> messes with roll centre". Well yeah this applies in compression during cornering for sure. But I'm not a stance cunt so what happens if I just stay with my superior German geometry ride height and travel? lol.
    Only slightly lowered. Iíve check all the arm angles, bump steer, and got rid of most of the anti squat out rear too.
    I want to get more consistent with times then start playing with bump and rebound against the clock.
    Itís already pretty fast and forgiving so I donít want to change too much.
    code
    Originally Posted by Tut
    THEY SHOULD ANALYY RAPE THEMSELVES WITH A FUCING CACTUS UPSIDE DOWN WITH COCONIUTS AND PINEABPPLES AS CHRISTMAS BALLS THE FUCKNIG THIEVENG CUNTS ID RATHER DIE FROM HAVING A RAINBOW UNICORN URETHRALLY RAPE ME THAN TO FUCKNIG DO BUSINESS WITH THEM CUTNST EVER AGAN

  28. #28
    Peoples Champ Fatboy's Avatar
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    Quote Originally Posted by bp18t View Post
    Will i die?
    Eventually yes. But from aids, not cocking a wheel during hillclimbs...

    If it's fast and feels solid cornering go with it. Trying to fix it will probably fuck the balance you have now if it's only getting slight oversteer....
    The older i get, the better i was...

  29. #29
    aka SpaZdA (tm) mondo2000's Avatar
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    With car set up you can fall into a bit of a trap, where if something feels good to the driver, you go too far in that direction. The Escort handled pretty much as you described and the driver thought it was awesome "because it is getting so much drive out of the corners which is very important on hill climbs." Which is true, up to a point. It stops being true when the driver is focussing on the drive out of corners, he is maximizing that, but neglecting the corner up to the apex. Good drive feels good, so more drive must be better. Except it isn't if all you're doing is making up for lost corner speed.

    The stop watch tells no lies.

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