Wife gets sick...

Doesn't make any sense. Could just be an excuse because she wants the beamer, that simple.

Toyota and Lexus vehicles in general are very soft and mushy. They soften everything from the suspension to the steering wheel feedback. This is usually better for people who get sick in vehicles from motion sickness since you aren't moving as much. By contrast a BMW for the US market (not true outside of the US) is tuned to be what 'Muricans think is sporty, meaning stiff suspension and jarring bumpiness. You can feel a pea sized rock on the road. This causes the whole thing to bounce and jiggle aggressively but all the time. I would think this is worse than a Toyota.

If she just wants a BMW for the sake of having a BMW, no amount of sway bars and braces will help because body roll and stiffness isn't the problem.

If you just want a harsher ride (ala BMW) bump up the tire PSIs to 42+ psi. That should jolt her out of sickness if that's what it is...

 

A new car is way cheaper than a new wife. Get the BMW.

 

The v Five, right out of the box, with 215/50R17 shoes, exhibits none of the issues you seem to be interested in solving.

There have been various reports of 'wandering', 'weathervaning', body roll, etc. on both hatchback and wagon, but we have not experienced them.

The v Five runs like a train on tracks on the highway, winds, trucks, no matter.

Before I modded up the chassis stiffness (assuming those add-ons actually work -- see some of "Mike-500" 's comments) I would look at tires/rims and alignment. If you're sensing fishtailing (yaw variation), for example, I would check rear toe-in and bushings, first.

 

Similarly, I was constantly feeling ill while riding in my wife's bmw 3 series.

I discovered it wasn't the BMWs fault at all but the presence of my mothernlaw in the back seat

 

I agree with Air_boss. I'm not sure if yours is the five, or not. But my v is a five and it is a VERY flat and stable ride. It is the least "mushy" riding Toyota product I've ever ridden in. It almost rides to harsh for my taste.

Also. A very important point, ALL v models have pitch and bounce control. Making the vehicle never sway and bounce.

Just this past weekend I experienced this working, I was driving down a for familiar country road, going pretty fast I went over a small little hill, this is where all my cars in the past would always make your stomach jump. Not in the v at all! Smooth and flat. Good Toyota!

Anyway I just wanted to put that out there

 

Sway bars and braces will stiffen things up a bit. I wouldn't waste your money on rims.....but rather get stiffer struts and King springs.
It is also possible the CVT is what she is reacting too....in which case, none of your mods will correct.

 

My wife has an X1, 7" of clearence, 32 mpg, for winters and trips, summers she drives the '11, gen3, so she can bring a dog, (leave the air on when doing errands) best of both worlds.

She's planning on turning the Prius into a Tessla 3, put down the money, methinks she will reconsider when she sees the size, but, it's her choice

I have a gen4 and a ram ecodiesel, winter are rough here.

 

Prius have a very comfortable ride! I think the issue is much deeper! That maybe she don't like the car period. And you wanted something a sportier, with more room and offers lot of mpg! I suggest to look into tires! First! Tires has every thing to do with traction grip, ride and rolling resistance ! There are tires that offer a little of all of these ! You can do all the performace suspension body bracing without the right tires it won't amount to much!

 

What is a pitch and bounce controller?

 

Are you sure she's not running a low grade fever or perhaps has a virus? The FIRST thing to do is to check air pressure in the tires and put them back to factory. The second would be a good suspension checkup by the dealer to ensure no broken parts or worn out struts (unlikely in most cases under 200k miles). The third would be to change tires to something like MIchelins.

As stated above, stiffening the ride will be counterproductive and just make you less satisfied with the v due to the significant extra expenditures that you can't get back if you sell. Fyi, my 2012 v3 (virtually the same as your 2013 v3) rides better than any BMW, small truck, or standard Prius that I have owned or ridden in. Not saying better handling than a BMW doing country switchback roads at 90 mph, but regular driving in a decent car. The pitch and bounce control uses the engine computer controls to counteract excessive undesired motion. My two cents...

 

See this article: Green Car Congress: Toyota previews Prius v; first expansion of planned Prius family

 

As others has mentioned, I don't think the braces and sway bars are the way to go. I have a 2013 V 5 with the17" wheels. The ride is pretty stable. I think a set of 17" wheels and lower profile tires would make the most improvement in the handling and stability.

My daughter has a tendency to get car sick in some cars but is ok with with our Prius.

 

I see thanks! so the v will ride like a small boat on waves without this system! Sea sickNess in a prius V is very possible if this system fails?

 

Rear sway bar is a must! I didn't believe the rear sway would do much because it's not attach to the body only stiffen up the torsion bar! But I found after installing a trd rear sway high speed tracking improved very much! Before around 75- 90!mph the prius need constance correction going straight! Now at even 90+ mph it tracks fairly straight. Fyi. I have cusco frt sway, frt lower brace, front power brace, center brace rear brace trd rear sway, RSR springs, went from 17" to 16" wheels michelin premiere A/S tires! It's a stiffer ride! Vs stock! But it's really handles! It won't be like our c7 / mx5 .

 

What's the deal with auto-correct-by-website of Mike -- 500 to "Rude person"?

 

It sounds like your wife wants the BMW regardless and you want the stiffeners and 17" tires and rims regardless. You really should find a 2012-14 v5 with the 17" low profile tires and test drive it. If she does not like the v3 with higher profile tires, I predict she will really dislike it stiffened up. The higher profile 16" tires with factory pressures absorb bumps and vibrations and don't really cause straight line problems at high speeds (85mph limit on our tollways and you still might get passed). The car can suffer slightly from high velocity cross winds at Texas autobahn speeds. High speed cornering is what you gain with heavy duty stiffening. Again just my two cents...(in an effort to save you thousands).

ps: The 17" wheels will throw off your speed and distance calibration. Factory final drive ratios went from 3.27:1 on a standard Prius to 3.70:1 on the Prius v which is the significant reason for lower mpg but better load capacity.

 

Skip the mods and just get a Tesla.

But yes....new wheels will throw off speedo

Sway bars will be huge