xb2

I picked up the TRD swaybar and TRD tower brace. I am debating on getting the NF210 or TRD springs and installing them at the same time. Also got the foglights to install too.

I put on a surfboard roof rack, but I drilled the top and It was a little scary at times. It looks much better than the clamp on versions because there are more options for placement.

miketf1

love the way you worded that! you might have just convinced me to get NF's!

CIONIDE

iTrader: (1)

xb2, the NF's drop the rear a little bit more that the TRD's. I think it evens out the ride height better, but that's just me.
Additionally, the spring rate is just a little softer on the NF's. If you do a lot of daily commute driving,
I'd recommend the NF's.
If you drive more aggressively on winding roads a lot, you might be better off on TRD's. The decision is yours.

xb2

I got my username.

CIONIDE

iTrader: (1)

Nice and to the point.

Guest

Everyone always has an easy install at the shop. HAH. :D

Yeah come on out, Daniel will be there too with his custom 08 xB. :D You can get some ideas and meet new Scion people too. Everyone that shows up will be from Scionlife.

ScionFred

iTrader: (1)

I stand corrected. I assumed that since Hotchkis claims that their front sway bar is 50% stiffer than stock that their rear bar would also be 50% stiffer. In any case it seems that Hotchkis using such rounded-off figures indicates estimates so perhaps we should assume that the Hotchkis bars would be somewhere between 25-50% stiffer than the stock front/TRD rear combo.

Now I'm far from an expert on this topic but I do know that stiffer sway bars do tend to limit side to side suspension compliance as well as body roll and therefore contribute to a firmer overall ride. Whether or not you would even notice any ride quality difference between TRD and Hotchkis is debateable and I wouldn't presume to know the answer. In theory, the Hotchkis bars should make the ride feel slightly firmer.

Another slight consideration is that stiff suspension/body anti-roll is great for dry pavement but can actually reduce traction under wet conditions. Race teams typically soften the suspension quite a bit for wet conditions and I've even seen teams disconnect both sway bars entirely for wet condition racing. Obviously we need a nice balanced solution so we don't have to make such suspension adjustments depending on daily weather conditions. ;-)

I think you'd be equally happy with either the TRD rear or the Hotchkis F/R set but I'm not too keen on matching the Hotchkis rear bar with the stock front. It might work just fine but IMO it probably wouldn't match the stock front bar very well.

I haven't forgotten about the BU light problem either but it's on the back burner until Spring. I did learn that there are 3156 50W halogens available cheap and that the base can be easily modded to work in a 7440 T20 socket but when I test-fitted a 3057 bulb (same dimensions) I discovered that the bulb glass diameter is too big to fit through the opening in the BU lite assy. As things stand now I'm looking at modding the housing to use a halogen 3156 or a 35W H8 or just replacing the stock assy with a 4" round fog light and rewiring.

BTW, I'm diggin' your new springs. If I didn't already have the TRDs, I'd probably get a set of NFs.

MikeInABox

I think if someone is going for upgrading the suspension while trying to retain the daily driveability and/or comfort, the TRD sway bar is probably the way to go. It'll cost less and be one less part to remove/install. This is just my opinion, as I haven't installed my TRD sway bar yet. I've been debating what springs to get until this post and my NF's are on the way. Just seems like it wouldn't really be worth the extra money and work to install if you're more worried about comfort and whatnot. I think the Hotchkis would be more suited for someone with the DF's or coilovers that wanted the most cornering improvement they could get.

CIONIDE

iTrader: (1)

Thanks ScionFred and MikeInABox, sounds like TRD rear only is the easy way out that will probably be more suited to my driving needs. This one part just sounded so appealing: "90% lighter", but I'm not autocrossing it or anything like that, so not much need to tighten up the handling that much.

Bigfieroman, any engineering input that we all might be missing here?

Thanks everybody.

And Mike, congrats on making the NF purchasing decision - You gonna love 'em!

MikeInABox

Thanks man. I've been wanting springs since I got the car (back in July), but waiting to see what would be available. The wheel gap has been driving me nuts.

I went through slammed and stiff ride with my VW, and I don't want that this time. As much as I'd love to drop it on DF's I don't think I'd be happy with the ride. Plus I wouldn't drop that low with stock shocks and struts and would have to spend more for that.

CIONIDE

iTrader: (1)

Not just the wheel gap; the ride and handling is worlds apart also. You'll be happy you waited, while at the same wondering how you went so long on the stock springs. (What we don't know, can't hurt us. )

MikeInABox

LOL, yeah I know what you mean. This is the first car I've had that I waited a while to do anything to. I just told myself over and over again that stuff will come out and if I buy something right now, I'll probably wish I had waited when something nicer comes out. I guess that came from experience, because I changed a lot of stuff more than once on my old car before I was happy.

Unfortunately I think I'm at the point of no return. Because I know as soon as my springs and sway bar are on after this weekend, I'll get something else. Ah the curse of being into cars. lol.

Bigfieroman

Here is a PM I sent to HotchkisSusp weeks ago:

*****

HotchkisSusp wrote:
Bigfieroman wrote:
Do you guys have any idea how your rear bar stacks up stiffness wise to the 7/8th" thick solid rear TRD bar? I tried to do the calculations, but I need your rear bar's inner diameter to do it.

The Hotchkis sway bar is 25% stiffer and 90% lighter then the current TRD Rear bar.


I think you misspoke above, I think you meant that the TRD bar weighs 90% more than your bar, not that your bar is 90% lighter...90% lighter means it weighs 1/10th of the TRD bar's weight. If your bar weighs 10 lbs, that means the TRD bar is 100 lbs.

I finally got my swaybars today (Christmas gift) and measured the wall thickness of your rear bar.

Assuming your bar is of similar material properties to the TRD bar (which is listed as SAE 1026 Cold Drawn steel), I did the following calculations.

The equation I used for torsional constant is (pi/2)*(OD^4-ID^4).

The TRD bar is 22mm (they also say 7/8", which is a little bigger, but I will assume it is actually 22mm solid), and I calculated its constant to be 0.8841.

Your bar is 1" OD and 3/4" ID (I measure wall thickness at 1/8", but this is a rough measurement, my calipers are at work), and so I came to 1.0738 as the constant.

0.8841/1.0738 * 100=your bar is about 21.5% stiffer, assuming an identical material, moment arm, shape, etc. You said your bar is 25% stiffer, this is close enough, I assume the difference is just rounding.

On the weight side, assuming that the bars are identical in shape and density, I calculate the TRD bar to be 71.5% heavier (OD^2-ID^2, dropping all identical coeffs). You meant that the TRD bar is 90% heavier...I don't know where the discrepancy comes from.

Could you explain the differences? Perhaps your bars are made out of a stiffer steel and have a thinner wall thickness than what I measured? I am sorry for being a pain in the butt, but they would take away my degree if I wasn't...

Anyway, I cannot wait to install these things, they really seem like they will clean up the handling of my xB!

*****

Anyway, her response was that I was wrong, the rear bar is 25% stiffer and 90% lighter, and gave me her engineer's contact info. I didn't bother because it was obvious that she didn't really understand and I didn't care that she was misinformed.

As far as ride penalty for stiffer bars, it is true that added roll stiffness will make the ride A LITTLE stiffer, but unless you drove the cars back-to-back, you would probably never notice.

One factor that no one mentioned is unsprung weight. Because these bars are lighter than the stock front and TRD rear, the unsprung weight of the suspension is reduced, which improves ride and handling. It basically allows springs and shocks to work more efficiently and filter out more of each disturbance. This works in a different way than the ride penalty for roll stiffness, so they don't cancel each other out, it means that in some situations the Hotchkis setup would ride SLIGHTLY better, and in some it would ride SLIGHTLY worse. The difference from non-progressive springs or 18" wheels will be much more noticeable.

The part about roll stiffness in wet conditions is true as well, but it shouldn't be a huge effect on a street car. A race car goes from "unbelievably stiff" to "stiffer than any street car" for wet conditions, and it drives at the limit ALL THE TIME. As long as you aren't drifting every time it rains, you will never notice the loss of cornering due to the bars.

I think I am going to start charging you guys an hourly fee.

CIONIDE

iTrader: (1)

Thanks Biogfieroman, very informative; and they can take away your degree, but they can't take away your knowledge.

Sounds like for what I'm after, the TRD will serve the purpose fine.

Your comment about 18" wheels and unsprung weight sparked one last question:
If I go with a forged 18" wheel/tire combo that is lighter than the stock steel wheel/tire combo, will it still produce a noticeable difference in suspension feel and handling?

I know the 18" set-up would place more rotational mass toward the outer edge of the tire/wheel diameter, I just don't know if this would change the suspension response since the overall amount of unsprung weight would be the same, or possibly even less.

BTW, if you charged an hourly fee it would then become work instead of fun!

Bigfieroman

Well, the difference in unsprung weight that an 18" wheel and tire combo, even a cheap one, is pretty negligible. For instance, my setup is ~4 lbs heavier per corner, and it cost $875 with tires, etc. Going to the Hotchkis setup over the TRD/stock setup would save about 10 lb/axle or more, so it already makes up the whole difference. In addition, the effect of unsprung weight on handling /ride is a pretty weak one.

The big difference you feel with bigger wheels is the increased sidewall stiffness due to how short the new ones are. The sidewalls are also why you have a rougher ride; the sidewall of the tire is an integral part of the suspension and is accounted for when they design the chassis. The weight of the rim has no effect on this.

Keep in mind that some people have complained that the TRD swaybar is not very noticeable. It makes a difference, but the Hotchkis combo is supposed to be great (mine will be installed this or next weekend).

MikeInABox

LOL. I was about to say, if it's 90% lighter, how much does the TRD sway bar weigh???? 90% lighter is probably a better sales pitch, but doesn't make any sense, as you've pointed out.

I think I'm going to put on my TRD sway bar before I put on my springs. It will be here a day before my springs anyways. I know it would be easier to do it when I do the rear springs, but I want to see what difference there is. If I do it when I do the springs I probably won't notice the specific change the sway bar makes, if that makes any sense. If it doesn't seem much different, I'll just sell it and get the Hotchkis bars. I'll let you guys know what I think.

CIONIDE

iTrader: (1)

Yeah, I'm well aware of this; in fact it's the reason that I have been torn b/w 17" or 18" wheels. I think 18's look much better, and now that I feel how great the NF springs ride I'm definitely going with 18". In an effort to keep the speedo accurate, I figured I would go with 225/40 like most of you, until a recent discovery.

The stock speedo calibration appears to be WAY OFF! A couple nights ago I was passing one of those radar trailers that police park on the side of the road to get people to slow down. My speedo said "32" while the radar had me at "30". Toyota strikes again with exaggeration on the side of safety (protecting us from ourselves).

Ultimately what this means is that a slightly larger diameter tire (up to about 6%) will make my speedo more accurate, not less. The stock 205/55-16 has a sidewall of about 4.5", and a 225/40-18 is about 3.5", If I go with 225/45-18 the sidewall will be 4" tall, and the diameter will increase 1.1" to 26" (this is only 1/2" larger than TRD 19" tire/wheel combo). This will result in filling out the huge fender openings by an additional 1/2" all around, as well as giving me significantly more sidewall than 225/40's, and it will still handle much better than the stock 16's.

I am aware that the odometer will be a little off, but I'm OK with it showing a few less miles than I have actually driven.

Bigfieroman

I have found the speedo to be pretty close. Those radar units are not the be-all end-all of accuracy, I measured mine using milemarkers on the highway. I would say my speedo is, at most, 1.5% fast. Tire wear makes a bigger difference.

Here is a tip; if you want a nice ride with those 18's, stick with the 225/40-18 (it is a much cheaper size, anyway) and get a tire that is described as "luxury" or something that is only H-speed rated. You will give up a little in handling, but the softer ride compared with V, Z, W, or Y rated tires sounds like what you are after.

xBliever

I was noticing the speedo difference when I was right next to a newer Civic with their own digital speedo reading, which is very easy to see from a lane over. He was a good 3 mph less than what mine was reading. I think Car and Driver did a test on several vehicles a while back and found them all to be over or under a few clicks. I don't think it matters if you normally simply follow the basic speed law of not driving too fast for conditions. And as you said CIONIDE, odometer shouldn't be too big a deal.

xseveredveganx

All I know about swaybars is how they work.

Bigfieroman, *big thumbs up*.

When I get another truck rolling, want to design the 4link and front control arm setup?