The Fit does have more understeer than I like. I was getting used to it, and it's not like I do any racing, but the idea that it could be for some absurd legal reason made me mad enough to try disconnecting the swaybar as suggested. I have exactly zero years experience adjusting suspension tuning, but nonetheless it was quite easy.

Sure enough, it makes a huge difference as reported. I just did this, haven't tested it much yet. There is more body lean, sure: It's very noticeable that it rolls more easily at first, but when it's at maximum angle it's not as obvious to me that it's all that much more. Does that make any sense?

3% better lap time from a driver who presumably knows what he's doing seems like a good sign, so I will leave it like this at least until I have a chance to test it a bit more thoroughly.

 

Okay, it didn't take long for me to get impatient to go for a drive to a road where I could push it a bit in relative comfort and safety. Very first corner of hard driving, I throw it into the turn, failing to notice the stream of water running across the road from the melting snowbank. Snap! OVERSTEER! The car was right sideways. Lucky for me my driving instincts have not been erased by a year of driving the Fit which never previously did this, and there was plenty of room to slide a bit wide since that's why I chose that road in the first place. Now I go back to normal driving, and *will* have the patience to get to a race track to re-learn the car before I even think about taking a corner that fast again.

To sum up the rest of my drive: Yes, this is an improvement. BIG THANK YOU to mahout for saving me many dollars on the probably less-effective suspension mods I'd no doubt have eventually been tempted to try.

but do it at your own risk! ... bears repeating. This substantially changes the handling of the car, and I for one am not qualified to judge whether it's going to kill you our your car.

P.S. Anyone know how big a job it is to remove the swaybar completely?

 

sfenders- hahaha, you sound like me. i can't wait when i do
something new.


how was expressway speed stability?

 

Well, unlike mahout I didn't yet get to anywhere near the limit of grip while above 50mph. For one thing I'm on new tires too, having just taken the winter tires off last week. So I don't really know where that limit is at high speed, just that it's way faster than I usually want to go.

I did try some quick lane changes, which seemed fine, though some more of a lean to the side obviously. Otherwise didn't notice any difference. I do have Airtab vortex generators on the rear roofline which probably provide a wee bit of downforce, and also reduce the wake turbulence. I did notice some difference when I put them on last year.

Hmm, now it just needs a rear diffuser and maybe some stiffer springs...

 

The stock Jazz/Fit spring rates are as follows:
2.55 front / 5.2 rear -kg/mm

Now we just have to translate from metric to the right way inches....

 

Claymore, are you sure about those numbers?
Doing the conversion that would make it roughly 145lbs/in front and 290lbs/in rear.
That has to be way off US/Canada models considering where spring rates are for Eibach Pro's (currently on my Fit) or Progress. Eibach Pro's are linear 159lbs/in front and progressive 182lbs/in rears and feel considerably stiffer than OEM's. During our "spring evaluation meet" (data posted on "Spring Comparison" thread) somebody mentioned that OEM rates are 120lbs/in front and 150lbs/in rear. Judging by "butt dyno" that feels about right (too soft!).

Disconnecting front sway bar is the oldest Auto-X trick in stock class. I have done it on my CRX autocrossing in early 90's. I eventually added ST front and rear SB which added stability at high speed, but did nothing to improve balance from mediocre understeer. I ended up putting OEM front SB back in and keeping fat ST rear. That gave me more neutral handling, but still required bumping up adjustable Koni's on the rear quite a bit.

kenchan & mahout, you are both right in your assessment, but truth is right in the middle!

I believe that going to extremes on either end is not the right approach. We are forced to do it out of necessity and lack of right tuning parts!
It is too much of a compromise! I would love to try much softer than OEM front SB and rear Progress SB (adding Progress rear SB and with OEM front SB eliminates quite a bit of understeer, but car is still understeering!). That would do the trick IMO.
To me there is no brainier that disconnecting front SB will eliminate a lot of inherited understeer, but going without it will make the car feel loose at high speed not to mention unmanageable with cross winds on the fwy. Stock Fit is scary enough with cross winds!

Mahout, I believe that aftermarket springs you have eliminated a lot of negative effects of disconnected OEM front SB.
I would not advise anybody to disconnect it while they have OEM springs - body roll would be even more excessive!

Mahout, you are also right on understeer being mandated by government regulation due to nothing but human nature. It is not just in US, but world wide. Under panic moments of car control loss, it is natural for a inexperienced driver to hit the brakes. Cars are the safest impacting with the front since crumple zone is the largest and most capable to absorbing impact energy and providing safest outcome for the passengers. If law was not enforced, oversteering cars would frequently impact sideways which would provide less than half of the safety margin given by frontal impact, not to mention of a greater possibility of a rollover reducing survival even further.

It scares me reading about everybody bolting everything they can find for their cars without ever attending an auto-X, performance, or survival driving class/school! Those actions caused too many lost lives already!
People, outrunning your friends up the canyon does not make you an expert driver! It just proves your friend is even less skilled!
There are enough of us here that learned that the hard way, but fortunately without paying the ultimate price - dying!

Link to spring rate table I put together from data I collected from fellow members and my own research (contacting manufacturers):
https://www.fitfreak.net/forums/fit-...tml#post228261

Ivan

 

Could be not correct I "borrowed" them from another Fit site so it's very possible something is not right.

 

im not sure why you're stating that im at the other extreme... cause
im not. i only stated that my estimation based on previous experience
is that the car is going to feel sloppy and unstable on expressway
speeds when you unlink the front stb. but i was also willing to try it
if i had a stock Fit. i don't.

i never said anything about adding a heavier rear swaybar on the
car,etc. if you follow my posts regarding my car on other threads, i
even removed the rear swaybar after trying it because i was not
really happy with the artificial feedback. plus with the c/o's i have
now, my car runs fine through crosswinds for a tall narrow car and
the dynamic feedback i have throughout the range of the sus is
natural.


i agree about the comment on trying these things out on the street.
thus, i posted try "at your own risk" on my earlier post. i know wat
could possibly happen especially on expressway speeds...as you said,
unstable.

 

Mine seems quite well-behaved at speeds well above what I normally do, but that specifically is what my little aero mod helps the most with, aside from the reduced drag.

Also forgot to mention that my wheels are +40 offset, increasing the track width by 3cm. Not by choice really, it was just hard to find inexpensive light-weight wheels with stock offset. At a guess, that probably reduced body roll by about as much as the swaybar disconnect has now increased it.

 

Mahout,
I'd like to see the results of your testing as well, both for the springs and the shocks. That information would be very helpful to me in selecting replacement shocks for stock-class autoX competition. The spring rates are just good information to have, especially for those folks not bound by Stock-class rules and are contemplating a spring upgrade or full coil-overs.

As for the shock dyno curves, both KONI and QA-1 publish curves for their products, so that shouldn't be a big deal from a legal/liability standpoint. I realize that giving away the hard work you do for a living is another standpoint entirely. Ultimately the shock dyno curves are (for me) "good to know" but not as important to me as the spring rates, since the springs ARE going to stay on my car and the shocks/struts are NOT.

HF

 

Who in the aftermarket tells customers what spring rates, free length, coil wire diameter they are offered? They don't for the same reason we don't. There's too great a chance that someone will misinterpret of simply err and that will cause grief. Its enough to specify the amount of lowering expected to provide enough information for a cogiscent customer to buy.
We tell people to lower an inch to 1.5 inches; going beyond that must result in a hard uncomfortable ride that is likely to have suspension geometry and handling problems. And after hundreds of vehicles lowered we think that rule is justified.

 

TEIN USA | MODEL&PRICE | HONDA

for one, tein displays their spring rates... not the diameters of the coils though...

 

Doesn't Eibach with their ERS series of springs?

 

I think Eibach has that kind of data for lots of their springs, so the info is out there if you're starting from scratch. If that's the case, all you really need is free length, rate, and DIA to see if a given spring will work. Starting with an unknown spring means measuring and running some numbers to get the rate, using the spring rate formula:

Rate = [(G) x (d^4)] / [(8) x (n) x (D^3)]

where:

G = 12,000,000
d = wire DIA
D = coil DIA at center of wire
n = number of FREE coils

Not rocket science by any means, but the numbers don't fall out of the sky. Unless someone who's done the work throws them out on the intarwebs for everyone to benefit from... wink-wink, nudge-nudge...

HF

 

Actually, that's a good observation about appearing to initially have more roll but finally not much different.
Did you feel a reduction in effort it takes to 'carve' the corner? To us tyhat was the biggest advantage.
And does 'testing more thoroughly' mean an A/X? We'd be interested in that experiment too. Cheers.

 

Not so much physical effort, reduced force on the wheel didn't make so much impression on me perhaps because I was used to cars without power steering. It was certainly easier to control though, response to steering more predictable, which seems to make sense if the front wheels get a bit more traction.

I haven't done any Auto-X or anything else since the 90's, hadn't really intended to with the Fit. But yeah, I'll give it a go when the season starts.

 

Yeah, a lot of work that come resale you may want to put it back in stock form. And just think what might have happened when you understeered in that cross-stream. bet you'll check out test corners before you test next time.

 

No re-sale expected, I think I'm keeping this one. Autocross next month, and though I don't intend to care about the results so much, maybe there is some chance I'll get more interested in further modifications, so leaving it alone for now.

That first corner big understeer skid wasn't so bad, though sure enough I haven't done it again. A casual observer might have thought it a bit of intentional drifting. Besides, the car did exactly what it was supposed to there.

But I did find a disadvantage to this lack of front sway bar; not something you'd notice in normal driving street or track, but I was in the middle of a large-radius curve at fairly moderate speed when a deer jumped out in front of the car. Suddenly applying hard braking in the middle of a turn seems to result in rather more sudden movements in pitch and roll than I'd expected. It wasn't all that bad, but I'm guessing probably more alarming than it'd be in unmodified form. So if anyone else tries this, that'd be the thing to test.

 

Any such sudden reduction in speed is likely to result in more understeer, which is likely to propel you straight into the sudden obstruction or off the road or into oncoming traffic..
When I ecounter a deer, and so far 3 times, I held course braking reasonably and nailed that deer amidships. I and my cars continued on, the worse for wear, but the deer never recovered. One of those incidents involved a 125 lb deer and a Geo Metro XFi weighing 1600 lb. And the front antisway bar was removed from the Geo. Anything you can do to 'hold your path' is a real benefit. Whatever you do nail the deer rather than run off the road.