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    High speed braking=SCARY

    K so I was driving kind of fast the other day (90-95) when someone going the speed limit (50) decided to switch lanes. Long story short I had to brake pretty hard and it scared the **** out of me. The car felt so wobbly and just unstable. I was extremely dissapointed by this experience and to be honest don't feel very confident behind the wheel anymore. Is this normal? Has anyone else experienced thks? Hoping there is a quick fix for this (lowering?) Thanks

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    Quote Originally Posted by Vlavsky View Post
    K so I was driving kind of fast the other day (90-95) when someone going the speed limit (50) decided to switch lanes. Long story short I had to brake pretty hard and it scared the **** out of me. The car felt so wobbly and just unstable. I was extremely dissapointed by this experience and to be honest don't feel very confident behind the wheel anymore. Is this normal? Has anyone else experienced thks? Hoping there is a quick fix for this (lowering?) Thanks
    Dead easy fix mate....

    Drive at a sensible speed for the safety of yourself and other road users and save this **** for the track!

    Oh yeah, welcome to the forum!

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    MY braking has been of a quality high varied due to road conditions. I drive acccordingly, and do not consider the berakes to be any worse than good...but they aren't great either.

    Quick fix, change brake pads to a more performance pad...if you are willing to accept more brake dust, reduced pad and rotor life, and the need to properly warm the pads for best performance. Lowering would likely make braking worse, as it reduces suspension travel, and your wobble is probably road condition (crappy roads, uneven, etc) related.
    Last edited by DuckDodgers; 09-09-2013 at 10:37 PM.

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    haven't noticed any issues in autcrossing or at the Abarth Experience, although neither one involves HARD braking from 95.

    Top speed on the track at Abarth Experience was about 86 down to maybe 40 for a corner. No issues.

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    All 101HP all the time Lifetime Member Felnus's Avatar
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    It's a short wheelbase car, the rear will unload under panic braking but the ESC and anti-lock brakes should keep you pointed in the right direction which is what you felt, the car battling physics to keep itself and you in one piece. 45 mph over the speed limit is asking for something bad to happen. Slow down before something life altering occurs and a squirrelly rear end is the least of your worries.

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    You were doing 95 in a 50, and the "dangerous little car" kept you going in the proper direction without plowing into an innocent person driving like an adult. It worked fine, and you need to cut that **** out.
    2013 Abarth Cabrio, Nero w/ Rosso stripes/mirror caps, Nero cloth, Comfort & Convenience, Beats, clear bra, Turbo tails, Platypus front plate holder, Tributo Ferrari key fob

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    Totally agree with what others have said about minding speed on the highway, and using caution to not put others lives in danger as well as your own.

    That said, I think I've actually experienced the feeling OP is talking about, actually at much lower speeds as well. I think it's a issue of weight transfer. For me it's happened right at about the threshold of braking before a turn. Probably just short of engaging ABS. Being front weight biased and having a really short wheelbase definitely exacerbates the feeling. For me it wasn't a uncontrollable violent feeling or anything, just that the car felt like the rear got a little nervous feeling for a second, and still being a bit new to the cars handling characteristics at the time, was also a little nervous myslef for a second lol. The car sorted itself out though before any input on my part was necessary. But I could see how it might unsettle someone if they didn't expect it.

    I think what's happening is the rear of the car is getting very unloaded under fast sharp braking. From my experience though, the rear only does it's little wiggle when it happens over uneven or somewhat rippled pavement. Since there's so little weight back there, the wheels are light for the second, and is easier for them to follow all the imperfections in the road.

    Under normal driving, you'd just about never notice it. Under hard driving or in a panic situation on sort of grooved or rippled pavement is the only time it rears it's head. I would say the solution is dampers with more low speed rebound damping in e rear, or more low speed compression damping in front. I'd personally probably opt for low the low speed rebound in back, I like bump damping to be compliant. It would slow the weight transfer under extremely hard braking. i imagine any kind of uprated damper would probably sort this.

    All that said, it's hardly any kind of deal breaker for me. This car handles excellently! Like I said, the car sorts itself for the most part before it ever really "gets out of shape". The only place I could see it being a issue is if the driver did something erratic, or over reacted when it happened. As is, nothing is really needed to compensate other then just keeping the steering wheel straight, which is what you want under threshold braking anyway.

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    Quote Originally Posted by Vlavsky View Post
    K so I was driving kind of fast the other day (90-95) when someone going the speed limit (50) decided to switch lanes. Long story short I had to brake pretty hard and it scared the **** out of me. The car felt so wobbly and just unstable. I was extremely dissapointed by this experience and to be honest don't feel very confident behind the wheel anymore. Is this normal? Has anyone else experienced thks? Hoping there is a quick fix for this (lowering?) Thanks
    As others have said, upgrade the springs to something with a higher spring rate to help control the weight transfer from back to front. There are other ways to control front/back weight transfer but springs would most likely be the cheapest. A little toe-in on the back wheels may help too.
    Nero & white 2012 Fiat 500 Abarth - wife's toy
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    I'm not a physicist, but I read an entire book on braking, and one of the points they made is that changing the energy (heat) of forward motion is what stops the car, basically the ability of the braking system to absorb and get rid of the heat from braking. So while tire grip, pad performance, rotor interaction, etc are all factors, the biggest limitation is on having enough MASS in the system (rotors mostly I guess) to dissipate the heat.

    I'm not arguing either way since I'm not a scientist or in Formula 1 and NASCAR, but that's what the book was talking about.

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    I was at Summit point last weekend.

    Braking and especially trail braking is somewhat twitchy feeling.

    A couple points to consider.

    Mass and ability to absorb heat has nothing to do with this. That only is important on the track with repeated braking and relates to the vehicles ability to repeatedly brake without experiencing pad fade, cracked rotors and/or fluid boiling. On the street you will probably never have this issue and it has nothing to do with twitchy feeling.

    Increasing rear pad friction (adjusting brake bias towards the rear) will generally increase the chances that the rear will rotate. However, it is not that simple because with the lose suspension in the Abarth, weight transfer during braking also plays a role and increased rear bite might reduce forward weigh transfer.

    Couple easy suggestions to fix lose feeling under threshold braking include:

    1) alignment (zero or slight tow in at the rear)

    2) sticky tires will increase grip/traction in general and may reduce instability. Of course, sticky tires are also going to increase braking power and increase weight transfer forward which is not what you want to do.

    3) Suspension changes (shock and springs). Rear swaybar should not really do much here unless you are trail braking.


    I found the stock pads completely inadequate for track use (no surprise here). I got 4 laps before experiencing some fad, when I pitted in they were smoking terribly. Probably should have done longer cool down lap. Pad material was smeared all over the front rotors. Rear pad/rotors look fine. I generally never use street pads at the track but CarboTech has not yet made pads for the Abarth. Need to pull them and get some pics so they can start making these.

    My short term plans are better tires and track pads. The twitchy feeling might feel a little weird but the car generally does not want to rotate (even with the Neuspeed bar). I think that a short wheel base, narrow car with a high center of gravity is just never going to be the beast braking or handling car.
    Tie Your shoes, Drive your car, Love your girl. -WP

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