BT Tech stiffening plate question

<div class='quotetop'>QUOTE(Davey Bob @ Oct 14 2006, 02:17 PM) [snapback]332777[/snapback]</div>

It's not really a matter of size, buthow effectively it ties together the two weak points in hte car's chassis. The stock brace is actually a bit smaller than the BT. If the car didn't need a brace there, Toyota would not hav eput one on. By replacing it with the stiffer BT plate, it further minimizes flex in this area.

It may look small, but it is the right size. It does the job it was designed for quite well.

 

I achieved the same results many say they have gotten from this plate with a simple alignment by Toyota (free) - aligned to +.05 on each front wheel, it drives quite well and does away with the wandering feeling people have complained about.

I'm still not convinced that the Prius was not designed on purpose to have the degree of flex in it that this plate changes. Since I can't figure out the engineering dynamics, I'm going to believe that Toyota put some thought into the design. I'm quite happy with the way the 06 Prius drives since getting it properly aligned and putting new tires on it (Pilot Exalto A/S 205/60/15).

 

<div class='quotetop'>QUOTE(Davey Bob @ Oct 14 2006, 02:17 PM) [snapback]332777[/snapback]</div>

Not this again...it's not as chassis/suspension part. Toyota calls it a floor brace.

 

I don't care what it is technically called but installing the stiffening plate on my 06 made it handle and track down the highway much better. I was ready to get rid of my 06 unil I installed this part on my car. I have owned high performance sports cars so I know what good handling is and what differences the plate made on my car. I even took it off and put the stock flimsy brace back on just to make sure the differences I was feeling was not imagined. It wasnt so the stiffening plate is back on my car and staying there for good!

Ken
2006 Prius #6




<div class='quotetop'>QUOTE(BobZ @ Oct 14 2006, 03:04 PM) [snapback]332790[/snapback]</div>

 

<div class='quotetop'>QUOTE(Ken Stewart @ Oct 14 2006, 03:54 PM) [snapback]332805[/snapback]</div>

And exactly where on the suspension does this bolt to? The white tin floor pan in the picture below? There is a picture there of the frame too....hmm, no floor brace there either.

 

<div class='quotetop'>QUOTE(Davey Bob @ Oct 14 2006, 03:17 PM) [snapback]332777[/snapback]</div>

I installed the new plate the other day in just a few minutes. I used a torque wrench that clicks when you reach the set torque. Didn't even have to jack the car up but I did make sure I was on the level part of my driveway. I don't drive the car much because the wife drives it to work all the time. After the installation, I asked her how the car drove the next day. She said it seemed to handle & drive a little better. Then again she told me (after I had changed the oil one day) that the car seemed to drive better. So there you go!

 

I can only tell you the results that I had with my Prius. I do not claim to be a suspension/frame/chassis engineer but I can tell you that the plate has made my car handle and track better. I can definately feel the increased stiffness the body has compared to when the stock piece of tin was in it. I even took the plate off and took my car for a drive just to make sure that the differences I was feeling was not imagined and when I put the stock plate back my car had that disconnected crappy tracking trait all over again. I am only reporting my experiences with the stiffening plate and if you chose to dismiss it that it your choice. For me it made all the difference and is what caused me to decide to keep my car rather than trading it in or selling it for something else.

Ken
2006 Prius #6

<div class='quotetop'>QUOTE(BobZ @ Oct 14 2006, 08:47 PM) [snapback]332881[/snapback]</div>

 

<div class='quotetop'>QUOTE(BobZ @ Oct 14 2006, 03:04 PM) [snapback]332790[/snapback]</div>

Actualy, the plate bolts to the chassis. That would make it a chassis part. The suspension also is attached to the chassis.

 

<div class='quotetop'>QUOTE(BobZ @ Oct 14 2006, 12:04 PM) [snapback]332790[/snapback]</div>

If you know what it's not. What kind of part is a floor brace, then?

 

<div class='quotetop'>QUOTE(DocVijay @ Oct 15 2006, 12:46 AM) [snapback]332921[/snapback]</div>

Not so Doc. Go take a look at the picture. That is why I posted it. Then go take a look at the PDF file. Look at the numbers next to the part called *floor brace* Those are torque specs. Metric, Newton Meters and Foot Pounds. That PDF file is from a Toyota Prius shop manual Do you really think suspension part is held in place with a mere 22 Ft./Lbs. of torque to sheet metal..?!



<div class='quotetop'>QUOTE(Presto @ Oct 15 2006, 12:54 AM) [snapback]332926[/snapback]</div>

I work for Cadillac an went as far as to put in a call into Cadstar which in my direct link to the engineers. Cadillac uses the floor brace system too. Same kind of part, same location. Used on uni-body cars to prevent an "oil can" pop-flex in the floor pan. Nothing more nothing less

 

<div class='quotetop'>QUOTE(BobZ @ Oct 15 2006, 08:03 AM) [snapback]332977[/snapback]</div>

But how does it prevent 'pop-flex'? The way I see it, is the BT plate 'braces' the chassis so that it can't flex in that area and cause pop-flex on the pan, and it also stiffens up the backend. I'm satisfied to call the BT Brace a chassis piece.

 

<div class='quotetop'>QUOTE(BobZ @ Oct 15 2006, 11:03 AM) [snapback]332977[/snapback]</div>

Yes, so. I don't need to look at the picture. I know all about it already. Yes, it is a "floor brace." However, you seem to be confused as to what the actual parts of a car are. The "chassis" is the main structural support for the car. On older cars and still on trucks, this would be the frame. On newer uni-body cars it IS the body, there is no separate frame. It is one large structure that is welded together to form the chassis. Anything that bolts to this is a chassis part. You seem to be stuck on the idea that this also means suspension. No, the suspension is separate from the chassis. It also is bolted onto the uni-body structure. The suspension is a chassis part as well. Pretty much everything bolts to the chassis on a modern car. So even though the BT plate is replacing a "floor brace" it is still bolted to the main structural part of the car, also known as a chassis.



In this picture of a typical unibody car, you can see the red structure that is what is most closely related to the frame. However, in a car with a frame, the body merely sits on top of the frame. Here if you bolted a plate like the BT to the floor, it would indeed simply be a "floor brace."

However, in a unibody like in the picture (and like the Prius), the frame is NOT a separate part. It is integral with the body and all of it forms the cars base structure. When you bolt a part like the BT plate to this, it is a "floor brace" in name only, because it simply describes where it is bolted. It is, in fact, a chassis brace that reinforces the structural integrity of the cars total structure. It is a chassis brace.

It is NOT a suspension part as you keep referring to. The suspension is a completely different and separate part that is also bolted to the chassis.

You also refer to the torque specs. It is likely that this is all that is neede for this particular part of the chassis. It probably doesn't experience as much force as other parts of the car, so that is a sufficent amount of torque to bolt it on.

 

<div class='quotetop'>QUOTE(DocVijay @ Oct 15 2006, 01:24 PM) [snapback]333014[/snapback]</div>

Short and sweet...That's not a Prius and yes I mention the torque spec because something of such "Structural Integrity" would require more than 22 ft./lbs. I've installed and driven a car with one and the effect is placebo at best. The tire upgrade is where you'll see the improvement. Plus most of you are on Integritys and 40 plus lbs of air what do you expect? You've been under the car just like I have (I'm guessing) so explain how that floor brace is gonna affect that rear axle ???? In short...I isn't!!

 

Are we going through this again?

Bob, I think it's great your car handles to your satisfaction without any modifications. You're lucky.

My car tracked just fine. Very straight. No need to have an alignment. However it did not handle to my satisfaction on the clover-leaf on and off ramps on the freeway. I had to keep the speed below posted to feel safe. I put the BT plate on my car and I'm fine now. The rear end of the car doesn't seem to sway. The car seem to be "tighter". Placebo? I don't think so. That's my opinion. You have yours.

I'm sure Brian would cheerfully accept any returns of the BT plate and refund the purchase price to anyone who bought it, installed it and found no change. I'm not sure how many people have done this. Perhaps Brian would share.

Myself? I'll never take it off the car. And as long as Toyota puts the flimsy one on, I'll be replacing it with Brian's BT plate first thing.

I'm also confident that if there is ever a way to test the thing, it will turn out not to be a placebo at all.

 

<div class='quotetop'>QUOTE(Godiva @ Oct 15 2006, 05:11 PM) [snapback]333095[/snapback]</div>

As I've said several time before, the handling of the car is much improved (IMHO) over the stock brace. There are some who won't be convinced, no matter what anybody says. That's fine, they don't have to purchase the brace.

What I'm curious about is that TMS regularly follows the posts on this Forum and has never seen fit to comment on the utility of the brace. How about it Toyota? Why was the original brace developed?

Next question: Does the 2007 vehicle have the same brace as the 2006? Does the touring edition have the same brace?

 

<div class='quotetop'>QUOTE(Godiva @ Oct 15 2006, 05:11 PM) [snapback]333095[/snapback]</div>

Great now we have women mechanics...or more people who paid a lot of money for something and won't admit it was a waste of their money. Maam there is a straight axle in the back of these cars. That floor brace has bubcus affect on a straight axle. Here's from the Prius shop manual


<div class='quotetop'>QUOTE(syclone @ Oct 15 2006, 05:44 PM) [snapback]333104[/snapback]</div>

And I drove your very car and it is no different than mine!

 

<div class='quotetop'>QUOTE(syclone @ Oct 15 2006, 04:44 PM) [snapback]333104[/snapback]</div>

Dave Hermance brought a 2007 Touring to the October meeting of the Prius Club San Diego. I had an opportunity to stick my head under it in the parking lot while the rest were having brunch.

The brace is identical to my 2005. I don't know about the 2006 or the regular 2007 but I'll assume it's the same brace for all.

They'll probably keep using it until there is a major redesign. So when I trade in my 2005 for a new model, I'll buy another BT plate.

 

<div class='quotetop'>QUOTE(Godiva @ Oct 15 2006, 06:03 PM) [snapback]333109[/snapback]</div>

I didn't even notice the San Deigo part. My step son is out there and looking for a Prius