I've been thinking lately how I would like to improve the higher speed stability of my car. So far it's got a-spec springs, Koni Yellows, Progress RSB in the soft setting, and urethane front swaybar bushings with the stock bar.

I know all about the effects of a larger front bar on a FWD car so telling me I'm going to increase understeer and have trouble putting the power down exiting a corner is pointless.

How I came to this conclusion is this.... With the Konis and a-spec, it's as stiff as I'll take it for a nice sport luxury daily driver like the TL. I refuse to compromise ride quality anymore than I already have. I find the high speed (over 100mph) stability a little lacking. I can turn the Konis up a little when I plan on going for a fun drive through the twisties but it's more than just a damping issue.

With the Progress rear bar in it's softest setting, the car will already oversteer. Just the other morning on the way to work I hit a yellow light in a double left turn lane. I hurried up to make it because I hate it when people run the turn lane red light and as I went around the turn faster than any sane person would, the car got pretty sideways. So I'm not worried about understeer. If I get understeer with the larger front bar I still have two more stiffer settings in the rear bar to neutralize it.

So that plan is to either:

Run an H&R front bar which is 28mm solid and adjustable.

Or...

Run a TL-S bar that is 27mm solid.

This would be a huge difference from my auto 25mm hollow bar that's on there now.

The H&R is around $330.

The TL-S is around $68.

Since I can already fine tune with the rear bar, I'm thinking of using the stock TL-S bar since it's so much cheaper and only 1mm different.

The diameter change alone would increase stiffness by over 36%. With the fact that it's solid vs hollow, I would expect something in the neighborhood of an 107% overall increase in stiffness.

In comparison, going from the 17mm stock rsb to the 24mm is a 297% increase. Going from the manual 20mm rsb to the 24 results in a 107% increase and I've heard it's a noticable improvement for the manual guys.

I feel safe with the TL-S bar because coupled with it's stock 20mm solid rsb, there are no reports of any massive understeering or problems with spinning the inside tire exiting a turn (maybe that's partly due to the LSD). Still, it's factory so I know it's "safe" and it's cheap as hell yet is a signifigant increase in stiffness. As it sits right now, with the TL-S front and my Progress rear bar in the soft setting, mine should still handle more neutral than a stock Type-S.

I know I have to drop the front subframe but that's no big deal, I have access to a lift and most of my old tools from my mechanic days. Just got to find some urethane bushings for it now.

Any opinions and more importantly, has anyone done this before, auto to manual, manual to "S", or auto to "S"?

I really think this will greatly help with the high speed handling.

How about Type-S owners with the Progress 24mm rsb?

 

Another option:

https://acurazine.com/forums/3g-tl-tires-wheels-suspension-97/new-shock-tower-bar-fastline-performance-edfc-compatible-1-piece-steel-730039/

 

I should add that once it gets here, I'm going to see if there's enough meat and machined area at the endlinks to drill a second hole to make the lever arm shorter so I have the opportunity to adjust it while on the car to make it stiffer than a stock TL-S bar if need be.

After looking at some more solid vs hollow comparisons, I've come up with an increase in stiffness from 107% all the way to over 280%. I really wish I could get some solid numbers.

 

That's a completely different animal with a completely different purpose. A strut brace does absolutely nothing for bodyroll or balancing of the handling. All it does is increase the stiffness of the body, not suspension.

IMO, an aftermarket one is a waste on a car that came with one from the factory. No need for a solid unit on these cars and I doubt anyone would ever see a difference besides a very slight potential for less rattles.

 

I say quit racing and build a futuristic sub box. Then you wouldn't need to install a front sway bar.

Problem solved!



















Sorry Matt.. this was the best I could do. I can't offer an ounce of help to you on this.

 

I would just buy a stock TL-S front sway bar and add your old urethane bushing if u can..

no point in cashing out and extra $250 for 1mm unless ur that anal

GL let us know what happens

 

I'm waiting on your results, because I know your reviews are more realistic then others on the forum. I didn't know our stock front sways were hallow, now I'm inclined to change it too. I'd go with the TYPE S just because its cheaper and only 1mm difference, in real world will you notice that? That's what you gotta ask yourself. And also like you said, there are TYPE S owners that are running the Progress, so you'll pretty much be on par with them.

 

Is there a difference between the Type-S one and the 6spd base?

 

Solid vs hollow.

I've been trying to get some hard numbers on the difference. Depending on the wall thickness of the hollow bar, it could be 20% all the way to well over 100% between the manual vs TL-S.

The good thing is it should be a solid 100% increase in stiffness going from the smaller hollow auto bar.

 

That's true but 1mm does make a difference.

My urethane bushings for the auto bar will be up for sale cheap.

I'm planning on making the TL-S into an adjustable bar if at all possible. That way if it's not stiff enough with it in the stock holes, I can adjust it with it on the car.

 

Part of me wants to go with what I know is "safe" meaning the TL-S bar. The price is also right. But with the oversteer I already have and the fact that I can go up two notches on the rear stiffness, I could likely compensate for the stiffer front bar and at the same time add even more roll stiffness since it will allow me to stiffen the rear without upsetting the balance.

I know in the end I'll likely go with the TL-S bar but with the labor involved I only want to do it once.

I tend to get carried away, that's my personality, and I know the disadvantages of too large of a bar. I'm always conservative on swaybars and I like to get 90% of the bodyroll taken care of with springs. Unfortunately I won't compromise the ride quality of the TL like I have on cars of the past. That's the only reason I'm thinking the larger bars may be worth it. I'm not going any stiffer than a-spec springs.

On the bright side, I have several corners that I take to the limit on a somewhat regular basis when there is no traffic. It's the actual limit where either the front or rear slides and I know the speeds of each of these corners. So I'll know what difference if any the swaybar makes, not just going by feel like many do. I hate the typical swaybar reviews that say "the car feels more solid". Not exactly technical or descriptive.

Then I have a road that is in the middle of nowhere and pretty much deserted at night where I can take higher speed corners in excess of 110mph toward the limit. This is where I'm hoping to see an improvement. I typically take these at 8/10s for obvious reasons, I have had occasional accidental tail coming out but I don't like to do that at those speeds. What I don't like is the unstable feeling the car has and that's what I'm trying to get rid of.

So in 3 weeks or so I should have a review, likely of the TL-S bar in a base auto. I think this bar will be pretty effective considering my car is lighter than the TL-S auto by a solid 100lbs.

 

i'm sure that you are aware of how much of a PITA it is to change the front sway bar. I think member ACTROS removed his front bar...

 

Heres a crazy idea for installation:



1) Cutting the new bar somewhere in the center with a band saw, then have two brackets ('triangular' exhaust style) welded onto both cut faces.

2) Cut the old bar with a sawzall for easier removal and unbolt

3) Insert and bolts on new bar

I haven't looked closely at the how the bar is installed. But this idea should technically work with the solid bar, the only risky part is the welding, which would be better done by an experienced shop.

Also bolting the brackets may not be a breeze, but it sure beats having to drop the entire subframe

 

I don't think it's that big of a deal with a lift and tools.

The Accord guys seem to do it pretty often. Loosen two of the bolts, take out the other two subframe bolts and that's about it beisdes the normal stuff.

 

The front sway bar is hard to replace? Or are you being sarcastic?

 

It requires lowering the front subframe about 4". Not advisable unless you have a lift available. Personally I wouldn't have considered this but with the wreck, the subframe getting replaced once, then removed and replaced again due to a bad steering rack, I'm not feeling too guilty about doing it again. Plus it will give me a chance to see what all they screwed up when doing the repairs. I'm sure I'll find plenty things wrong.

If it weren't for lowering the subframe, it would be just like doing the rear, endlinks and U-brackets, and you're done.

 

I just noticed the '09 TL uses a 30mm solid bar up front. I'm sure the chances are slim to none that it would fit the 3rd gen TLs but does anyone know if it might?

 

I'm a retard I confused this with strut bar.

 

the h&r comes with urethane bushings. im not sure about the type-s?

plus h&r is adjustable

 

hate i think the 09 has the same subframe....

 

That would be pretty cool. 30mm and it's cheaper than the TL-S bar.

 

Do it and see if it fits. Be the guinea pig haha.

 

well i have the Progress RSB, Richie V6 strut bar, and a Type-S with stock suspension (besides the mentioned mods) and the handling at high[way] speeds is outstanding.

cant comment on the base (auto or 6speed) though.

 

I have had the backend kick out at 100+ and it was not fun. Add into the equation that my nuespeeds and koni's were adjusted to be on the stiff side as well and it was twitchy bringing her back in line. This thread looks promising, and hopefully we will see some real world benefits with little out of pocket costs.

 

Matt, I think you're on the right track. Go with the TL-S Bar, imho.

30mm solid might be too much. That's a LOT to make up for if it's past where you want to be. (BTW - the '09 AWD FSB is 31mm solid).

Regards the RSB: the Progress has 2 settings. How can you "go up two notches on the rear stiffness"?

 

I didn't realize until I started digging that the TL-S had a larger SOLID front bar. It's much stiffer than the base auto bar which would explain why I have oversteer with the Progress RSB in the soft setting and yours is more neutral. At this price, if the labor wasn't so bad I would buy the TL-S bar and try it for a while and upgrade if necessary but I'm trying to do this only once.

You dont have to use both front or both rear holes on the Progress bar. It's perfectly acceptable to use a front and a rear hole to get a medium setting.

 

Exactly. That's why I think the TL-S bar will be enough. I've NEVER had the car over-steer (except once on an abrupt throttle lift mid-turn; definetly not advised) and I've got the Progress bar on Stiff.

I realize your car is a tad lighter, but my guess is the TL-S FSB plus tweaking the RSB (soft, mid, or firm) and you'll find a pretty nice balance.

The labor to do it twice is just as bad whether you go too big or whether you go too small.






I did not know that. Thanks.

 

Thank you for the insight. If yours is for the most part neutral with the Progress bar in the firm setting, then going larger than the TL-S bar would only hurt handling.

TL-S bar it is!

 

Maybe I'm off my rocker, but how exactly would a stiffer sway bar, front or rear, improve high speed stability? Sway bars dial back/control lean in turns. When I hear improving "high speed stability" I assume the issue you have is vehicle wandering and floaty steering at high speeds while going going mostly straight. IMO, a sway bar isn't going to improve this because the sway bar only becomes active when you start turning and the car leans.

I've never driven a 3rd TL at high speed, but I've driven a 3rd gen TL 6MT at highway speeds and around town and found the steering a bit over-boosted at speed. I could see how this give a lack of higher speed stability. Don't get me wrong, the steering is really good, but maybe I'm use to my G's underboosted steering. My old Maxima had the same feel as the TL (granted my Maxima had a ton of suspension work).

IMO, the sway bar isn't going to fix the issue. One issue I see with your car is you're running 255/40R17s. These tires are technically too wide for the OEM 17X8 rim (they're made for 8.5"-10" wide rims). Additionally, the contact patch is now wider and narrower (more lateral traction, less straight line stability) because the section width of the tire is over 10" vs the OEM size of a crack over 9". The increase is section width is pretty significant and it can also lead to tire bulging on the rim. All this can lead to stability problems because the tire is operating outside of it's specified range and has different shaped contact patch.

Another issue is that rear sway bar. It sounds to me like it's overly stiff if it's causing snap oversteer, which is never a good thing. Either the sway bar is too stiff, even at it's lowest setting, or the tires simply aren't up to the task of providing adequate traction, or your Koni's are too stiff in the back or too soft in the front. Are these Koni Yellows? If so, they're really only adjustable for rebound. Great shocks though. I had them on my Maxima.

If it were me, I'd get the correct size tires and get ultra high performance rubber. More importantly I'd get an alignment and set toe, camber, and caster up for more high speed stability. Toe in the front slightly, the rear a bit more toe-in than the front, close to max negative camber front and back, and caster (if adjustable) a bit more negative.

 

The car oversteers now but the all out grip is much, much higher than stock.

I'm looking for a larger front bar partially to balance it out. Part of the instability may be from the tendency toward oversteer which the larger front will help.

At high speeds the car really needs more spring which I'm not willing to do. It's fine in a straight line at 130+ but taking turns at that speed, it has too much bodyroll and is flat out sloppy. It's not floaty and doesn't wander when going straight.

Tires aren't an issue. The contact patch is flat and going from stock to this size had nothing but positives in every category. This issue didn't come up from the tire change, if anything the wider/better tires lessened it.

Let's keep this in perspective, the handling is great and so much better than stock. I'm very picky, most people wouldn't have a problem with the way mine handles.

 

What size and type does a 6MT come with?

 

27mm hollow 6mt.
27mm solid TL-S

 

And coming from a 6MT, does the solid justify the upgrade? Sorry not trying to thread jack ya IHC, just curious.

 

yes it does bigtime! the ride feels so much more stable

 

Where in the world would one do such driving? Surely not in the US on our poor interstate highway system I suggest putting aside a large sum of money for bail, fines, and a lawyer since you apparently do this type of high speed driving on a regular basis. I'd also consider investing in a roll cage and R-spec tires. I'm not kidding either. Be careful.

 

once the lights are out and theres no one on the highways i consider them my personal racetracks lol

 

I agree. I pick and choose my places. There are a few spots I can take the car as fast as I can and not have anything to worry about. Doesn't happen often though.

 

me too. but again.....SUUUUUPER CAREFUL..... baconbits are everywhere nowadays.

 

I'm very careful with the time and place. Trust me, the only one that will be getting killed will be myself. As for tickets and such, I'll leave it with this.... the chances are slim to none of me getting in trouble.

I have Z rated tires, don't do it more than twice a year but I want the handling there for the rare times I need it. I like knowing it's there when I need it. It's sort of like daily driving a Ferrari, you drive it like a sane person 90% of the time but it's nice to be able to have fun once in a while.

 

Sounds to me like someone has access to a deserted airstrip.

Years ago I was doing work at an old AF base and it was decommissioned. It was late in the day and no one was around so I took my Maxima on the 3 mile long, 100 yard wide runway and let it rip. 130mph never felt so slow because there was absolutely no sensation of speed.