Chassis stiffening plate on '06?

I have the '05 loaded package and I would recommend the stiffening plate, small rear spoiler painted to match the car and a set of 17" Scion (Toyota) wheels. Those 3 changes made a big difference in my car.
Good luck.

 

I got the stiffening plate and it made a HUGE difference. I have the spoiler on order. If your 06 doesn't have it, get it. Easy to check. Just look under the car.

 

Why did you wait so long? I live in a small town too, 14,000, but I think we only have about 3 or 4 prii.

I have the chassis stiffening plate on order and am anxious to try it. I don't know for sure but I have heard rumors that they (Toyota) are using the same plate for '06 that they used in '04 and '05. I do not have the handling problems others have described but I installed the spoiler because of some instability in strong winds. I think it helped quite a bit and had no effect on gas mileage. See my spoiler mileage test in the performance mods forum.

 

Does anyone know if the 06 has a new chassis stiffening plate or is it the same one used in the 05 model?

 

So far no one has posted any definitive answers on this. I'm also waiting to find out. I'd like to know so I can order it and have it waiting for my '06.

 

And I'm wondering if Toms plate is better than Brians?...not to pit one against the other, but they are quite different!

 

OK, I just ordered one for my 2006. I'll be the guinea pig to see if it's needed or not.

 

Which one did you order?....

Toms looks quite elaborate, but I dont' know if its overkill... Brians looks by the pictures that it could give and take in the bolt holes and slip.. but I haven't seen one in person.

 

If you go to the Toyota site, there is a 360 degree viewer for the Prius. If you plop that puppy upside down....there is the old, small stiffening plate!!!

 

I ordered the BT plate.

 

Ha... thats a nice feature..I didn't know you could view that angle!

Looking at the bottom.... its hard to believe that little plate will do anything at all!....

What further amazing is that it even needs to be there at all!

but it appears reports say that it helps.

 

A good way to tell if its even doing anything at all is to completely remove it and take a drive!

It should be a noticable difference immediately!

To tell the difference from OK factory stablization to custom stabilzation will be a subliminal difference. To remove the plate.. if there is a BIG difference in not having it, then it may make more sense that adding a custom plate may help too!

But if when removing it, no difference is noticed, then its really hard to believe that a custom plate will help over the factory plate.

 

I will say, from personal experience, that the BT Tech stiffening plate improves the feel of driving my 2005 Prius. It is not subtle. I could tell an immediate and marked improvement in ride. No, it's not an FEM analysis, it just feels better.

The 2006 Prius seems to be substantially identical to the 2005 Prius in chassis and most mechanical systems. It also looks, from the 360° view on the web, that the OEM stiffening plate is identical. I would conclude that the BT Tech plate will improve the driving feel of the 2006 model. YMMV, of course.

 

thanks Bill.. I appreciate the input.
I know you are versed in this... based on what you know.. what is your present estimation of Toms brace?

 

I saw my 06 Barcelona Red #7 at the dealer today, and pick it up tomorrow morning.

I checked underneath, and it's the same thin stiffening bar as before.

This should be fun.

 

My estimation is purely logical since I haven't experienced Tom's brace.

With the tunnel that the exhaust system traverses, the chassis of the Prius (and most cars) is an upside down U. As you can imagine, the sides of the U can be pulled askew by lateral cornering forces, so the wheels are not parallel. The smaller OEM and BT Tech brace tie the closest part of the Ü together, assuming that the steel floor will help tie the outer edges, where the wheels are located, together too. Tom's brace tries to tie the outer edges of the Û together, since that's where the wheels are.

If there were a solid, machined brace, like BT Tech's, that went from outside edge to outside edge, like Tom's does, that might provide the most rigidity. It would also be heavy. The Tom's brace, composed of bolted-together components, seems somewhat flimsy and prone to distortion. While it might stop the spreading of the U, it won't affect the wracking of the U going around a corner. The BT Tech brace can't control the edges of the car, but it ties the floor on the right side to the floor on the left side together without much flexion. It rely's on the rigidity of the floor to keep the wheels parallel.

We know the Prius has a very high-strength steel passenger compartment, so there's a lot of rigidity there. So I guess that Tom's brace would work fine, though the span it's connecting is longer and it is more flexible.

So, my estimation is that the BT Tech brace is more rigid and likely to provide more rigidity to the vehicle. It also replaces the part that Toyota installed (they don't make a cross-vehicle brace), requiring only a simple swap, with better bolts.

 

Well, I will do some definitive tests to see what helps and what doesn't. I'm going to drive my Prius for a few days without any of the aftermarket braces. I don't htink I'm going to drive without the factory, as it was put there for a reason. Anyway, I'll try the BT brace, and I also ordered the Tom's strut bar brace and the front suspension crossmember brace. Eventually I'll get the Toms rear subframe brace and the floor brace. I plan on getting the Toms exhaust system, so hopefully that will eliminate any clearance problems. Don't know about the cat though. Maybe the Toms exhaust angles it a bit more so that the floor brace just clears the exhaust. If not, either a couple of grade 8 SS washers or bending the hangers a bit may provide just enough room.

My personal opinoin is that it doesn't really matter what scientific analysis shows w/regards to these types of mods. If the car simply "feels" better, tighter, or more solid, then that's enough evidence for me. Seat-of-the-pants meter is often accurate enough.

Anyway, pictures and reports to follow.

Upper Strut Brace


Lower Suspension Brace




Soon to get:
Toms Floor Brace


Lower Body Brace - rear

 

As usual, your a genius!.. very good explanation!
I can see how toms may do better if it does the same thing as brians, but even more with the extra pieces.. providing the weight is not bad...
Ill have to go look again to see where all the bolts go to see if it holds the "U" as secure.
thanks

 

Great.. let us know.. also let us know approx how much all of toms stuff weighs if you can.