BT Tech Stiffening plate

I could have not said it any better than this.



Frank Boyle


<div class='quotetop'>QUOTE(IsrAmeriPrius @ Mar 28 2007, 12:33 AM) [snapback]413354[/snapback]</div>

 

<div class='quotetop'>QUOTE(DaveLeePrius @ Mar 26 2007, 07:07 PM) [snapback]412578[/snapback]</div>

You seriously believe this? While I don't have the BT plate it is not because I don't think it would make a difference. My reason is more of whether the plate's performance is worth the cost, to me it isn't. I don't believe the average owner would notice much of difference to justify the price point. However, I do think auto manufactures have to give up what they could have done better to keep the product affordable. Many a garage mechanic has improved a factory vehicle. That's how the auto racing profession got its start.

 

Edited post

 

<div class='quotetop'>QUOTE(John in LB @ Mar 27 2007, 05:37 AM) [snapback]412835[/snapback]</div>

Come on John, stop impugning my veracity! If I say I felt a difference turning 90° accellerating out of a driveway, I did. I did back in 2005 too. You may believe anything you want. I believe you don't have an open mind. I believe you have a tight wallet. I believe you will never accept the experience of others as valid.

I suppose you could take your placebo and use it as a suppository.

 

I could "feel" the difference like Bill as soon as I drove out my driveway on to the street! Today I was in a left turn lane waiting for a light and trucks and cars zoomed past me at 40-50 mph just feet from my 07 touring.... only the biggest of the trucks and none of the cars made my baby shimmy with the air blast!

As for the test asked for in this thread by the skeptics, what driving conditions is that suposed to re-create? I have yet to have my front wheel up in the air on any D-A manuever I could pull off in my Prius! :lol:

 

<div class='quotetop'>QUOTE(Gadgetdad @ Mar 27 2007, 10:44 PM) [snapback]413414[/snapback]</div>

Ok... now, we have done it - All you have proven here is the Placebo effect.... If your car is standing still - I don't care what the BT plate looks like - It would have ZERO effect on your swaying car.

Unless you count the extra 5 lbs of weight as anchor - so you wouldn't get blown off the road as easily...



<div class='quotetop'>QUOTE(Bill Merchant @ Mar 27 2007, 10:12 PM) [snapback]413407[/snapback]</div>

Bill, I was not impugning your veracity - I totally believe you felt something. I just doubt that it was a dramatic marvel of engineering that you felt.


For all (not just Bill): The discussion seems to have turned ugly today - and that certainly was not the intent. All I was interested in was some numbers to back up the claim; and I did question the value proposition of the BT plate.

The topic is right for the FORUM. It is completely appropriate to pursue it here. And that is a fact that is not in dispute here.

I would suggest to all that we stay on topic and keep the conversation in a positive and constructive manner - and have a little fun too.

 

<div class='quotetop'>QUOTE(John in LB @ Mar 28 2007, 04:44 AM) [snapback]413440[/snapback]</div>

Think of Columbus trying the explain to Tomas De Torquemada that the Earth was round!

It's one thing - doubting that the BT Plate is effective. It's anybody's right to have doubts. It's quite another thing to try to rationalize not purchasing the product by claiming "placebo effect". This inherently demeaning to those who have purchased the product and are satisfied with its performance.

I purchased my Prius for several reasons - I wanted to save gas - I believe every cent we spend on galoline helps to promote World Terrorism. I am an unrepentant "tech nerd" - I truly believe that " He who dies with the most toys, wins".

I was initially very unhappy with the Prius tendency for it's rear end to steer the car in the presence of large vehicles, and certain kinds of road surfaces. It was disconcerting to feel the back end of the car moving around and requiring steering corrections. It really came down to purchasing the BT Brace or reluctantly thinking about selling the car.

I installed the brace and there was no doubt that the handling had changed! The rear end steering was virtually gone. The only time there was any inkling of the condition was in the extreme, like passing between two semis at 65 MPH.

That being said, I would venture an opinion that those on the forum who average 50 MPG and over probably would never feel the difference or gain any benefit from the BT Brace. You don't drive aggressively enough for the rear to start wagging. Nothing wrong with that - more power to you.

As I've mentioned before on this forum, I'm not an automotive engineer, but I do crew on an auto racing team in Grand American Racing ( a division of NASCAR). I've been driving and "messing" with cars longer than most of you on this forum have been alive.

Anybody has the right to doubt. The only legitimate way to impugn is to try it and say it doesn't work. I've been following BT Brace related threads for almost a year. I think I recall 2 posters that bought the brace and were not satisfied with its performance.

 

<div class='quotetop'>QUOTE(syclone @ Mar 28 2007, 11:31 AM) [snapback]413521[/snapback]</div>

There's the possibility that could be a psychological rationalization to avoid going to all the trouble of removing the BT plate, reinstalling the OEM plate, and returning the BT plate to the seller, i.e., "I just went to all the trouble and expense of buying and installing this thing, so it better work."

That's where all the nice machining and anodizing come into play. It'd be a lot easier to justify removing the plate and sending it back if it was a nasty-looking chunk of aluminum. As it is, it's an asthetically-pleasing piece that looks a whole lot better than the OEM brace (even if very few people ever get to see it).

 

<div class='quotetop'>QUOTE(rudiger @ Mar 28 2007, 12:02 PM) [snapback]413542[/snapback]</div>

Reading the instructions takes about as much time as swapping the plate. The doubters seem to try and focus on any explanation other than the plate really works and that's why people aren't sending them back. I know if I installed the plate and it didn't work it would be on its way back pretty quickly.

The level of denial here is rapidly approaching the "dogma" level. Referring back to my first post, maybe all you Flat Earth guys should write a letter to the Vatican and see about forming a branch of the Tomas De Torquemada Society. You could start your own forum and take on other controversial subjects like: Is the Earth round?, Does the Earth really revolve around the Sun? Was the Universe created 6000 years ago? Is Elvis really dead?

 

<div class='quotetop'>QUOTE(IsrAmeriPrius @ Mar 27 2007, 08:33 PM) [snapback]413354[/snapback]</div>

Hello IsrAmeriPrius

With all respect, you do not know my mind. Like you I admire the truth. I have read both sides and tried to find what is real and did my test. It was revealing.

The plate is held by four bolts, two on each side. The BT plate is called a "Stiffening Plate". Presumably this is because it is to prevent the distance between the two pairs of bolts from changing during operation of the car. I put the car body under maximum torque by supporting one front wheel until the back wheel on the same side was off the ground without a plate installed by these two pairs of bolts.

There was no detectable difference in the distance between the two pairs of bolt holes to which the plate is attached under this maximum body torque.

Is it unreasonable to inquire what the BT plate does with this information?

If the crowd says that the Emperor has fine clothes and I can see that he is naked does that make me a "naysayer"?

 

<div class='quotetop'>QUOTE(Allannde @ Mar 28 2007, 02:37 PM) [snapback]413621[/snapback]</div>

Hi Allende,

What dial indicator did you put between the bolt holes? How did you read the indicator while some body was pushing up and down on the unsuported corners? How much weight did you use?

Did you do any axial displacement measurements? How far did the holes misallign front to back when the unsuported corner was pushed up and down, left to right, front to back ?

You might be able to get both these measurements with two dial indicators mounted criss-cross. Then calculate the width wise and inline displacements.

Is there any data on the side forces up to 40 mph broadside wind? Did you push on the side of the car with the same force distribution as the wind and check out the gap variation ? One PSI is 144 pounds per square foot. One would think that with a good wind gust, one PSI migh occur between the windward and downwind side of the car. Total force might be on the order of 1000 pounds in such a condition.

 

<div class='quotetop'>QUOTE(donee @ Mar 28 2007, 10:08 AM) [snapback]413636[/snapback]</div>

Hi donee

First, I don't profess to be the final word on the matter. In former posts, I have called for others to do tests to confirm what I have found.

Second, my tests were not moving tests. That presents challenges which are beyond my means to do.

Third, I understand that the torsion test I did was the industry standard for this issue.

Fourth, the method I used was probably accurate to the thickness of a piece of paper since I was using a fixed reference point which did not change (a nail in a board held in a hole). Here is the tool I made to make the measurement.

Fifth, to answer your question about the torque test please see my second picture. Note that the jack stand at the rear is not supporting the car. It was put there so the car would not fall on me while I was doing the measurement (while it was under torque). The measurements not under torque were done with both rear wheels in the air. I did this all by myself. It was all static. There was simply no measureable difference.

Edit: Notice the second nail at the other end of the board. That went in the hole on one side and the caliper then measured the hole on the second side of the plate mount. Notice also that the nails go through to the opposite side of the board which was necessary to make the measurements.

 

<div class='quotetop'>QUOTE(Bill Merchant @ Mar 28 2007, 02:12 AM) [snapback]413407[/snapback]</div>

To inject a little humor into this thread:

There was the doctor that saw a patient that was about as stupid as he was constipated. After an examination, the doctor prescribed suppositories to relieve the constipation.

Several days later, the doctor called (yeah, right this is a fairy tale) the patient to see how he was doing. The patient said that he had taken all the suppositories over a 2 day period and that he was still constipated. He then said, "Doc for all the good those damn pills did, I could have shoved them up my nice person". :lol:

 

Wow. Now I'm in a bind.

I bought the BT Plate and installed it.

I noticed a difference!

Oh wait. There is no proof. It was the placebo effect. Now I'm screwed.

I can't take it off and sell/return it; I would know that it changed, and lose the placebo effect.

Can someone please come swap the plate back out, sell it and put the money in my bank account without my knowledge? Then I'd have the placebo effect of a better handling car (I live in the mountains and spend a lot of time on two-lane curvy roads), but I wouldn't have the plate and it's nonsense.


On a more serious note:
I seem to recall that someone was going to put a BT plate on one of four prii in their work parking lot and then let folks do test drives... Did that ever happen? If not, I might be able to do it later this spring....

It still may not prove anything as it would involve subjective, normal people. (I'd leave my car out as it's a Touring model anyway [OMG!? What if that doesn't matter either :blink: ] and I'd find other folks with prii.)

 

<div class='quotetop'>QUOTE(Allannde @ Mar 28 2007, 09:37 AM) [snapback]413621[/snapback]</div>

Just to be clear, if I understand what you did, this is the wrong measurement. I would expect that dimension not to change at all.

My understanding is that you measured the distance between the bolt holes (essentially the length of the OEM plate). That distance is not expected to change when the car is twisted - as you show in the photo.

The only valid measurement is the height of a reference point on the front of the car to ground. A change in that measurement (with the plate and without) is indicative of increased torsional stiffness.

 

<div class='quotetop'>QUOTE(MacDude @ Mar 28 2007, 12:25 PM) [snapback]413719[/snapback]</div>

I think a good test would be to have it with the OEM plate for a couple of weeks and the BT Plate a couple of weeks, but not let them know which part is installed. Then ask which week did the car handle better. Yes, it would require swapping plates, but the driver shouldn't know what the car has during the test.

 

<div class='quotetop'>QUOTE(John in LB @ Mar 28 2007, 12:31 PM) [snapback]413722[/snapback]</div>

Hi John

I did that measurement also, twice. That measurement came out identical as well both with and without the plate.

It just seems like a reasonable question to ask. If the bolts which hold the plate do not change position when the car flexes without the plate, what is the plate stiffening? That it not a rhetorical question. I want an answer.

And yes, I certainly agree that a double blind test is a good idea.

 

<div class='quotetop'>QUOTE(Allannde @ Mar 28 2007, 02:13 PM) [snapback]413768[/snapback]</div>

The plate (stock in this case) does pretty much, nothing based on your findings. That's why there's the BT plate since it actually does something.

 

<div class='quotetop'>QUOTE(Allannde @ Mar 28 2007, 12:37 PM) [snapback]413621[/snapback]</div>

Touche

Herbal supplements. Some people swear by them, say they help with arthritis/depression/colds/etc., even though for the most part they haven't passed rigorous scientific studies. Others aren't willing to put their money there based solely on testimonials. I can understand both points.

For me, I'm quite happy with how the Prius handles with the stock plate, so it's a moot point. I would think there are several people on PC for whom the Prius is the best handling car they've ever had, and it would be hard (rightly so) to convince us to buy this plate!

On the other hand, why should I care if you want the plate? No paint off my Prius... B)

 

<div class='quotetop'>QUOTE(Allannde @ Mar 28 2007, 01:13 PM) [snapback]413768[/snapback]</div>

The BT plate is so thick that it won't allow itself to be twisted. Therefore, when it is bolted to the car, it also prevents the car from twisting (at least in the region of the plate location).

By not twisting, the plate is trying to keep those 2 parallel beams that it is bolted to from twisting (relative to each other). The original OEM plate does not offer any such resistance to twisting.

Note, the BT plate is not expected to outperform the OEM plate in keeping the 2 parallel beams from spreading further apart or somehow coming closer together - as the car bounces around on the road. Your measurement is indicative of this type of performance.



<div class='quotetop'>QUOTE(Tyrin @ Mar 28 2007, 01:58 PM) [snapback]413790[/snapback]</div>

Just for fun here... Please name a car that you think is worse handling than the Prius. I am dying to know!