Need some help on upgrading suspension!!!

Look at my signature, I've done it all and love it. No understeer, flat cornering, lots of fun on on-ramps.

 

I didn't vote because you didn't list the two main ingredients for improved handling which are lowering springs and 17" or 18" wheels. Unfortunately the wheels will lower mpg and the springs may make driving up steep slopes difficult.

Sway bars help but they are minor improvements compared to springs and upsized wheels.

Ok, I'll vote anyway. lol

 

I'm pretty new to the Prius, just got a 2011 III three weeks ago.

Does this vehicle not come factory with a front sway bar?

 

It does but we are talking about thicker performance bars.

 

so, this is an interesting thread to me. While I enjoy my Prius, I would like to make it more stable on the freeway especially where wind and cross winds are concerned.

I drive mostly 70% freeway 30% city driving. Occasionally I have to go offroad - basically driving down a dirt road, jeep road, or through a field for parking when I attend mountain bike race events. With that, I don't think lowering the car or adding bigger wheels and tires are going to be an option for me.

Is there a way I can stiffen up the car a little and still be able to drive (very slowly) across a field without ripping the car apart?

 

I would start with the rear sway bar from the Prius plus pkg, followed by the Tanabe strut tower bar. Both are easily installed for a moderately skilled DIYer. If you really want to make a bigger difference, add the lowering springs from the Prius Plus pkg.

MB860 ?

 

Adding the Cusco center power brace and Tanabe strut tower brace & forward under brace will stiffen up the body significantly and force the suspension system to exclusively deal with uneven road surfaces rather than sharing the load with body flex. These will also help quiet body squeaks and rattles. The rear anti-sway bar should help with stability. None of these will make a difference going down a dirt road or driving across a field.

 

Sweet! I'm not necessarily looking to go off-road any better, I just don't want to lose any of the car's current off-road ability (such as lowering the car or filling the fenderwells full of tire.) Off-road ability is very VERY relative term. I'd just like to tighten up the suspension and make it a little more stable at freeway speeds while still maintaining the ability to do some light driving off the pavement.

 

All,

Now Toyota TRD offers rear sway bar and lowering springs.
toyota.com/prius-hybrid/plus

 

I have no data for comparison...but I want to agree with these comments. However one sway bar is a fraction of the cost for four springs, tires, rims. So I bow out.

 

Your local dealer should be able to order it for you.

The prius plus pkg lowering springs are only $225 or so and will lower the car more than some of the aftermarket springs. But since you need the ground clearance I would not bother.

Be careful of the braces too, as some of them will stick out slightly and reduce your ground clearance.

 

Larger wheels do not affect your ability to go off road. I do it nearly every day for work.

 

The Cusco mid-chassis power brace tucks in pretty well under the vehicle and doesn't compromise ground clearance. The Tanabe front under brace does stick down a bit, and I've hit this a few times on crossing certain speed bumps. I've ground down the lowest points near the bolt-up points on each end with a Dremel, and suggested to Tanabe that they not make those so protruding.

 

Is there any performance data that shows the improvement of the Performance Package? Slalom, turning G's, etc?

 

Do you need numbers? The package makes a huge difference in handling and cornering ability vs. the regular Prius Two-Four. The Five model already has 17" wheels so the difference is smaller but still very noticeable. With hundreds of posts from people who have done the upgrade I have yet to read about anyone not experiencing a huge improvement in handling, stability and cornering ability.

Try searching the GenIII Modifications forum. Lots of good info.