Increasing the Fit front bar from 21 to 22 mm almost required a 17 mm rear bar; those unfortunates who get a base Fit will understand the true meaning of understeer.
I didn't look but if the 17 mm rear bar can fit the 08's it would be an improvement although we still recommend no front or rear bars on 08's or 07's is best. That can change from track tests.

Note the 09's do not meet the wheel requirements for 08's.

 

Interesting.... I just looked under the car on the GE8 Fit.. and it does not have this sway bar..! Wow the USDM car gets something the JDM Fit doesn`t...

 

Actually, it's welded in on both ends. Measured around 17.7mm (probably paint thickness). Not replaceable unless you do a big swap out with the base Fit which would probably be going too far.

Caveat: This car is obviously brand new to me, so I'm still feeling it out.

This car is WAY too squirrely for me. The rear is proportionally too "active" above say 40/50 MPH with noticeable oversteer. I'll have to drive a base Fit to see if the rear 17mm bar is the cause as the remainder of the suspension I suspect is largely similar.

First thoughts are my Fit Sport desperately either needs some more toe in the rear (maybe getting too much dynamic toe change?) or a much larger front sway bar (or both). It's not too bad at lower speeds or once the suspension gets loaded up.

BTW, I've owned/driven/modified a good handful of Hondas over 30-ish years, and the handling of this one is the worst. I'm looking forward to learning what others are doing to their 2009 Fit Sports (aftermarket, JDM, otherwise). P.S. My other car is a very well sorted Boxster S which I thought sucked when I first got it, so no one take offense at anything I say.

 

Eeek, I'm coming from an S2K, if I am dissapointed I'm going to be pissed.

On a side note, I would think you would HATE S2000's if you don't like driving squirlly cars, my S2000 is trying to kill me. In the rain, it's like a death sentance.

 

You sound like the typical 'target' driver. Any hint of less than severe understeer is not comfortable. Thats why the 08's were such an understeering car. The addition of the rear antisway bar on 09's was necessary to improve roadholding and complementing the Stability Assist. That Assist may be whats causing your uncomfortable handling. Just as taking the front bar off 08's leads to much improved roadholding, adding the rear bar and slightly increasing the front bar (all the attachment points appear the same) has yielded a Fit that gains in roadholding even with that Stability Assist program.The lap times of an 09 on our test track are slightly increased over 08 and the gearing loss friom the larger tires (likely due to increased weight without torque gain) and the top speed is about 2 mph faster than the 08. That just backs the spec changes. However, in-corner times are very slightly reduced and that is believed due to improved handling even with SA.. (The 08 without front bar out does both.)
If going sideways is not your thing, using combination of throttle, steering, and brakes to control yaw, then you may need to increase the front sway bar just as you are considering. But then perhaps SA may have not let the change show up. And yes, I never found any handling assist programs that I like; they always got in the way of doing the right thing at the time.
PS as a racer and car builder over 50 years with experience with Porsches, including Boxsters, what did you do to your Boxster to get it handling to your liking? Interesting comparison, I suspect.

 

If you're coming from an S2000 you better be disappointed. The Fit is a gofer car, my S2000 was a race car for the street. And wonderful to drive in the rain, squirrelly is the definition of maximum handling in tenuous traction situations.

 

I'll try not to take that as an insult. Actually, on front-drivers, I prefer slight oversteer which can be balanced with power to the front wheels (although I don't know if the Fit has enough power to effect that). What is particularly unnerving to me (at this early point) is that the handling is not linear. I find it quite sloppy, independent of understeer or oversteer. That is what feels squirrelly most to me. I do not have VSA.

What kind of track/speeds are you talking? A car set up for one set of conditions (AX) is not going to be optimal for another.

Going sideways on the freeway is not my thing. Sideways is also not the fastest (or safest) way around a corner. The Boxster is my car. The Fit will be my daughter's. It just have to be fun enough for me to drive and unflappable, predictable handling for her and others in the family that will drive it.

I'm not comparing the two since they are completely different cars. The Boxster is only a reference since there does appear to be a crowd that tracks Fits (maybe not so much the '09s yet), presumably with some driving/tuning skills beyond wanting to slam it to the ground and put on a cold air intake. My Boxster suspension is a mix of Boxster S, 030, 911, GT3, aftermarket, and some custom components. It's an interesting combination, but it works really well for my driving style/preferences. One of the best measures to increase stability (mid-engined cars can spin like a top) was not the usual suspension tuning but aftermarket track rods to change the (dynamic) toe geometry. P.S. Glad to hear I'm not the oldest Fit driver here

As I said, don't take anything I write too seriously. I'm here to learn about these cars and this torsion beam rear suspension which is a new animal to me as is the Fit.

 

My brother had an S2000 which, sadly, I never got a chance to drive. The Boxster S and S2000 are supposed to be very close equals. From what pitifully little I know about the S2000, it would likely be a scenario of suspension tuning and geometry fixes to tame any of the S2000's vices. I love the mid-engine and am convinced it's the way to go on a sports car.

I think we are in agreement over a dislike of squirrelly = unpredictable behavior. I think mahout's description of squirrelly is more like skittish, which just means more touchy and you have to pay attention.

I would lean towards mahout's caution that you may be disappointed. The Fit (even "Sport") is not a sports car. It is a good-looking and incredibly practical car, which I'm trying to inject a little more fun into. For example, I think some sticky 205/50R16s should pep it up a bit. The factory Dunlop all-seasons are a rather odd-ball size and too pedestrian for me. You may feel the same after likely having some good rubber on your S2000. I'm eyeing the Goodyear Eagle GS-D3s on TireRack for $73 which should also do well in FL downpours. I don't care enough about snow/all-season tires to warrant purchasing another set of TPMS.

 

I noticed this "squirrely" thing early on on my 09 Sport under hard braking while turning the wheel a bit (to avoid ramming into someone who slammed on their brakes in front of me). The rear steps out, and once it does the fronts give a hint of side-stepping as well. This happened a few times under panic braking.

I immediately thought of ways to mitigate this hazard by switching to summer tires. I thought 205/50/16 would retain the sidewall height while the extra width combined with stickier compound would provide more stability under braking. At the same time if I get some stiff sidewall tires, like my Bridgestone RE050A Pole Positions, they'll drastically improve turn in crispness and response, have more feel and add more weight to the steering and will improve the handling overall. Plus roll, squat, dive will be reduced a little.

 

Braking and turning are definitely a recipe for helping the rear come out. Glad you're OK.

From my initial checking, it looks like 205s on the stock wheels should fit and clear suspension points. I haven't checked the full range of travel, but the dealer was selling 205s on 17s with unknown offsets. I don't know if anyone has actually tried 205/50s on the stock wheels yet.

The suspension is too new to me to figure out what it might need for my tastes, but better tires are always a safe bet. Living in L.A., you probably don't care much about wet weather much either. I was also eyeing the Direzza Sport Z1 Star Specs. The Goodyears aren't as sticky but have a lot more cushy sidewalls which might make them more tolerable to the others in my family.

 

Scanning through Tire Rack's site I find that 205/50/16s are not a popular size, thereby limiting choices. But I saw 1 or 2 that may work.

Questions is, how would 205 mm look on a 6" wide rim? The stock 185s bulge out from the rim a little right now, but that's because of the curved sidewall. Do you think 205 summer tires will really protrude from the wheel? I'd like to keep it as close to flush as possible.

 

Are you sure you clicked on the right buttons? TireRack shows 49 matches. For Extreme, Max, and Ultra high performance, there are 16 matches. For the stock size, there are only 2: the Dunlop A/S and Blizzak snow tires. Yuk. The diameter is right on, but the load rating is a little higher than I'd like which means you'd have to drop the pressures a little. I don't know how the TPMS works is this would freak it out.

According to manufacturer specs, the SP Sport 7000 A/S has a 7.6" section on a 6" rim, which is what we have. A GS-D3 is spec'ed on a 6.6" rim, so correcting somewhat gives 8.2". Similarly, the Direzzas would give about 8.1" section. This works out to 1/4" wider inside/out. Personally, I am looking for a little wider tire so that the wheels don't get curb rash. Others in my house are not so careful with parking. I don't think an extra 1/4" will make the tire look pinched on the wheel. The 205/50s that I looked at typically approved for 5.5" to 7.5" wheels. Hope that helps out.

 

Lol, I should've specified that I was only looking for 205/50s in ultra high/extreme or maximum performance only as I don't need all seasons here.

 

[quote=OrangeRevolution;430538]I'll try not to take that as an insult.

Certainly not meant to be insulting; its the target most cars are manufactured to. Porsche for example being one of the exceptions.
I've taught over 150 students in HP driving and after spending many years on track. Every student began with a fear of going sideways. They only learned what to do with it on track. There is NO learning on the interstate. The key to a good handling car is when the car loses traction, slides sideways, it does so at both ends simultaneously, (on an 08 Fit the front goes waaayyyy before the rear). Antisway bars are only ways to balance front and rear traction. They don't really help much in cornering power. Thats done with suspension geometry, shocks, and springs.

What kind of track/speeds are you talking? A car set up for one set of conditions (AX) is not going to be optimal for another.

Actually we find the base setup for ciompetition use is also optimum for the street performance. And yes, every track/road needs adjustments to optimize performance but major changes are not usual. Our A/X cars have alway been set up for more oversteer because car rotation is more critical in an A/X. But the base setup didn't change. We merely dialed in more oversteer withshrter 'arms' or used a heavier rear bar . We rarely found a need to change springs and changes to shocks were only changing the 'notches' on the adjustable shocks.

 

The rear has softer springs? Surely not; the 08 squatted on spring seats way too quickly. Where is that information from?
PS: I've looked at 2 Sports and they do have rear antisway bars - and drive like it.

 

A 205 tire is 8.07" wide with typically a 6" tread width. The sidewall extending 1 inch outside the rim width on each side is quite proper. Any time the rim width is pretty much the same as the tread width you are on firm ground.
You do not want the tire section the same as the rim width. That causes your tire to take a triangular section; it causes the tire to bow up in the middle & requires more tire pressure to get the tread flat on the ground.
And its definitely antagonistic to tire performance. Tires are designed to be 'squared up' with the road to permit the design to work. Spreading the sidewalls defeats that by eliminating the ability of the tire sidewall to flex more or less from the staic 'bulge'. Remember, a tire is really a big spring. Stiffening the sidewall isn't going to allow that.

 

Did you mean "stiffening" the sidewalls?

For this car I would like a more "on rails" feel, and with the OEM all seasons which have that bubbled sidewall, it won't provide that. A summer tire with its vertical sidewall is what I think it needs, but I'm a little concerned those sidewalls will angle into the rim, IOW extend beyond the rim width.

 

Ahh. The 'on rails' fealing is provided by the tire sidewall construction, the tread construction, and the profile rather than how they are mounted on the rim. The stretching of tire beads outward has nothing but poor results in tire performance. The inner edge of the tread is always pulled up from the ground when the tire is subjected to lateral movement if the sidewall is already stretched out and has no room to flex the bulge. In other words, some bulge is necessary for good performance. Some bulges flex more than others; you need the ones that flex just enough to keep the tread flat.
Check the rim width range recommendation from the tire manufacturer. Its better to stay within those limits, not at them.
For that 'on rail' feeling reduce the sidewall profile; a series 40 section using a 17" wheel will make your steering inputs instantly translated into steering angles which is what you want. I too need that response which is why I have 205/40x17's.
Choose tires with high performance ratings, which usually have lower wear ratings and stiffer tread construction. The construction is considerably stiffer than the all-weather type tires and contribute much to greater response. If you can, refer to TireRack's performance tests; they have graphs of lap times in dry and wet conditions. Quicker lap times are indicative of traction and response. Their subjective ratings are Ok but the lap times really tell the story like it is.

 

Yup, that's why I've been putting on Bridgestone RE050A Pole Positions on my last 2 cars. Expensive though.

 

Thanks for the reply. Hopefully, the basics are there, then. Back looks like a piece of cake to pull apart. Have you had the front of an '09 apart? I got stumped by all the new black plastic obscuring the strut top mounts (with no apparent screws accessible).

I'm guessing these things run on the order of ~200lb springs all around. That means a large part of the suspension is in the bump stops (or actually "additional springs" as Porsche calls them).

Some quick measurements of suspension travel in the rear lead me to believe there is about 1/2" of travel before the bump stops kick in. The front could be a lot more travel which may be what is giving me that squirrely/sloppy feeling. This would match my initial perceptions that the chasis settles out once you load it up.

If you've had the front struts apart, how much travel until the front bump stops? I guess that's my next step -- to pull the front apart. I looked online and the factory service manuals are not yet out. I read some cautions on popping the axles out on the earlier Fits. I would feel more comfortable pulling things apart once I can get a parts explosion, etc.