Finally had my Hotchkis FSB installed

[fastdreams]

Wow. This car needed that more than I thought. I installed my rear Hotchkis bar several months ago, ran with it at the track in the less stiff setting. Made a nice subtle difference I could work with. I switched it to stiff and it has been very driveable on the street, a nice upgrade.

However the achilles heel to this car at the track is front end grip. I can already tell this is going to make a very useful improvement. I've hit some of my usual twisties with the fsb installed and according to my internal gyroscope, this little mod has really improved turn-in, mid corner grip, as well as corner exit grip/ability to put down power.

2 days after the install, I had horrible clunking in the front over any bump. Sounded like the car was falling apart! I knew it had to be the sway bar so I put it on the ramps as soon as I had the chance, expecting the worse. The forums will drive you crazy sometimes - all the talk of hotchkis not fitting correctly had me worried. Turned out it was just the drivers side end link nut was a bit loose. I loosened both, applied loctite, and torqued them down. No more clunking. It's been a week.

Can't wait to hit the track again with this cheap and effective mod.

 

[bacarl]

...However the achilles heel to this car at the track is front end grip. ...

You know stiffening the front end (roll, damping, spring rate, etc) effectively reduces front end grip, right?

 

[fastdreams]

You know stiffening the front end (roll, damping, spring rate, etc) effectively reduces front end grip, right?

It's not so cut and dry as that. While it can be true that going too stiff in the front will reduce grip, that is not always or even often the case. To state that it is always true I have to respond that is a misunderstood falsehood.

If the spring rate is too soft, the car leans. When the car leans, more of the car's weight is shifted to the outside tire - this reduces grip because the tire can only handle so much weight. This will also have the effect of changing the suspension geometry such that the outside tire gains too much positive camber in that situation, so the tire is in an even worse position than before. Then think of the inside tire, with no weight on the tire it's grip is not being put to use. And what grip it does have is limited because of the lean angle causes that tire to go too much into negative camber only leaving a small strip of contact.

The end result of too soft spring rate is a slower entry, slower mid, and slower corner exit. Overworked tires, overheated tires.

With it firmed up, the tires are more balanced, have more grip, and you can apply throttle sooner. Less deformation of suspension geometry occurs, less lean, so less weight is placed on the outside tires, while giving a little more workload to the inside tire.

If you go too stiff, the inside tires will lift (reducing grip), the tires will skip and bounce over bumps (losing grip). If you have an amazingly smooth track surface then the stiffer the better, so long as the inside tires are not coming off the ground. That's where you'd rather have stiffer springs with good travel, rather than really stiff sway bars which will lift the inside tire. Let's face it, upgrading sway bars on a street car is a compromise so that we don't have to run painfully stiff spring rates.

 

[danagirl]

after autoxing this car for 2 years i feel that i will never need a fsb. The rear did wonders, but the front need nothing as it is with most fwd cars

but i guess diffent conditions require diffent needs, autox is a huge diff compared to actual track driving,

 

[Silver Ecstasy]

When I installed my Cobb RSB (stock suspension, RSB set at stiff which is the softest of the two), I took a few turns around town and I noticed how the car handled better but the front end of the car started to feel looser. Like, the rear of the car was tight and accurate however the front was slightly sloppier.

I have the Cobb FSB and MS lowering spring ready to install and i'm considering installing the Cobb FSB and setting it to "stiff" as well.

 

[fastdreams]

You are correct autox needs a different setup. I think I would leave my car as is though, I like the balance, and the rear is still quite a bit stiffer. I'd bet with the fsb that slaloms would be a bit quicker. Hmm maybe I'll hit up the autox next weekend as a test. It's been years. Cool thing about suspension setup...if I find that I don't get enough rotation as-is, I can adjust other things. More negative camber will give more rear rotation. I have camber plates. Also I can put the car on the scales and change the height to put more or less weight f/r. And then the coilover dampers can be softened or hardened as needed. If all else fails, I can work around a handling issue with tire pressure.

With some fwd cars you want to set it up so that the rear is so stiff that it does lose grip - the classic 3-legged dog show. That of course gives you that needed rotation.

There seems to be two schools of thought for fwd autox car setup. I've seen some national top finish caliber cars/drivers where they went with a ridiculous fsb. But it seems that most go for the giant rear bar to get that blessed rotation.

 

[fastdreams]

When I installed my Cobb RSB (stock suspension, RSB set at stiff which is the softest of the two), I took a few turns around town and I noticed how the car handled better but the front end of the car started to feel looser. Like, the rear of the car was tight and accurate however the front was slightly sloppier.

I have the Cobb FSB and MS lowering spring ready to install and i'm considering installing the Cobb FSB and setting it to "stiff" as well.

I don't believe the cobb fsb is adjustable like the rear. Same with hotchkis. The cobb bar is actually bent to cobb's specs by hotchkis. The cobb fsb is 35% stiffer than stock, so it won't be too dramatic, and 90% in stiffest setting in the rear. should make for a nice neutral car.

 

[Silver Ecstasy]

This is just my imagination but the mindset on stiff fsb/less stiffness in front could also be based on driving style.

My logic behind this would be:

-if you're an early braker, neutral speed into the apex with power hard out of the turn, a stiffer front end would work. (If you are a late braker, a too-stiff front would overwhelm the tires and you'd just understeer like crazy)

-for the late brakers, rear rotation is a must as you're already diving into the apex later and the front needs to be a little forgiving.

I've also seen pictures of ms3s with rsb's and the rear camber is good while the front outside wheels are getting much heavier positive camber. So I'm also using that observation in my thought.

Does this sound somewhat correct?

 

[fastdreams]

Interesting thoughts.

I'd have to experiment with it to see how that works out. I think either way you drive, if the car is too stiff or too soft the results will not be great. That is my goal, to improve the car while keeping it neutral - not too stiff and not too soft. It is a bit too soft from the factory IMO.

Braking is one area where I'm usually braking too late and too hard. It's a hard habit to break (haha) as I'm fighting my hard charger instincts. Usually it is not the fastest way around the track. What I'm trying to train myself to do is brake a bit sooner, and brake a little bit less.

Right now I wait sometimes too late so I'm out of shape and trying to make it up mid corner and corner exit. For the tighter turns this results in lots of wheel spin with excess throttle. I hope that with the slightly stiffer front end, some of that wheel spin under power in tighter corners will be reduced.

There are some corners where there is just nothing I can do but be patient and wait for traction to come back. the car is leaned over, the tires are spinning as I'm trying to accelerate, I'm gently unwinding the wheel so I use all of the available track. that situation should be improved with less lean. I hope to knock another second or two off of my time at HHR, using the same tires.