Hotckis sway bars v. TRD rear sways v. Cusco sway bars

I have your option 1, TRD rear sways (Scion XB 2008+) & using stock front sways + Tanabe STB with stock springs and find it working great. There was a report of installing Hotchkis and finding it too much, car loosing too much grip. Cannot comment on Cusco, except that it is too $$$.

Another option for you would be TRD rear, and if you find you need more get xB front take off or one from RAV4 (it is 26mm and ~38% stiffer)

IMHO this car needs STB it significantly improved steering accuracy. Tanabe does not require reservoir relocation, and it is only $110

 

I have your option #1 PLUS the Cusco underbrace, Tanabe front underbrace and Tanabe NF-210 springs. Ride is NOT mushy - in fact, the dealer Prius tech (guy in his 20's) called the ride "stiff" (LOL). I think bracing the bottom really reduces body flexing, which is the most likely source of the "mushiness", and the STB finishes it off.

 

What do you have your tire pressure set at?

 

Fairly new Bridgestone Ecopia EP100's at 38/35 psi. I've learned that these tires actually yield 10% poorer mileage if the pressure is raised to 40/38 psi as I had the OEM tires set.

Edit: I ran the pressures up to 42/40 and drove my normal commute. HSI reads 53 MPG, has read up to 55, so I retract my earlier statement about raising pressure on these tires & decreasing MPG.

 

Wow I didn't know scion xb stuff fit pm our car.. Any other parts fit?

Btw I have tein htechs and 18x8 wheels.. Car feels soo much better now.. I don't think I need any bars with this combo.. But I have lost about 5mpg..

 

Try raising the pressure. I find that anything lessthan 40psi feels like mush. I run 44 psi in my 15" dB Super E-Spec tires and 48psi in my 17" Primacy MXM4.

DarkMatter, how did you test this idea? It's flies in the face of theory and tests done by other members.

 

Yes, I've tried raising the pressure twice and observed an mpg hit on the HSI after a few miles. Dropping the pressure back to factory specs restores my lost mpg. I reset Trip B each time to monitor mpg.

I also note the "conventional wisdom" that higher tire pressures generally yields higher mileage. These are unusual tires, they have a red thread visible at the bottom of the tread. Does their rolling resistance go up with pressure? Apparently so. It would be interesting to hear from others with these tires.

 

Yes, I've tried raising the pressure twice and observed an mpg hit on the HSI after a few miles. Dropping the pressure back to factory specs restores my lost mpg. I reset Trip B each time to monitor mpg.

I also note the "conventional wisdom" that higher tire pressures generally yields higher mileage. These are unusual tires, they have a red thread visible at the bottom of the tread. Does their rolling resistance go up with pressure? Apparently so. It would be interesting to hear from others with these tires.

 

I have front brace which was installed after running Tanabe STB and TRD swaybar for a few weeks.. while it somewhat improved front grip it barely registers, perhaps placebo effect? On other hand the concern would be the reduced clearance, esp with 1" lower springs.

2008+ Scion xB front also fits

 

Blizzard5 - Part of that mushiness comes from your spring choice. Eibachs are progressive unlike almost all the other springs for this car. Swar bars will help in the corners but they won't fix the mushy feeling so you may eventually want to swap to other springs.

 

That is interesting. I realize you are on the forums enough to know how we badger people about creating tests that are as accurate as possible and rule out environmental conditions that affect fuel mileage.

17"-19" tires make a huge difference in ridding the Prius of mushiness when combined with springs. The 15" tires are not bad but handling is compromised.

 

Well, rear sway and STB will keep your car more flat and keep it from leaning into corners. However, it will not help with the mushy feeling, which I associate with the compression and rebound of the springs and shocks.

 

Didn't you just get a Tanabe Front sway bar? how are you liking it so far? I saw that they added it to their website.

 

Interesting discussion, here are my experiences:

My setup on my PIII is (in the order of modification):

1. Stock Yoko15" tires @ 42psi front /38 psi rear
2. Tanabe front under brace
3. Cusco center under brace
4. Eibach springs (love them)
5. TRD rear sway bar

The overall handling of the car improved quite nicely as I installed each part. My next step will be to install 17 or 18-inch wheels and tires (probably the most effective change) and possibly a STB.

Part of the mushiness you are experiencing may be from lower tire pressures than I run. After a tire alignment and rotation at the dealer, they set the tire pressures at 36/34 psi. On the drive home I felt like the car handled quite poorly until I increased the tire pressures back up to 42/38psi where the handling became crisper and the ride firmer.

 

Yes, I'm testing the front sway bar for Tanabe. Honestly, the Prius is a sexy handling beast with the FSB. Handling and steering feel is improved, and the Prius just grips! The FSB is showing on the Tanabe website but is currently not available for sale yet.