BT Stiffening Plate Review

I just had my BT Stiffening Plate installed on Saturday! And yes, it does make a major difference in the stability of the car. The car rides smoother on bumpy roads, it is isn't jostled around so much in the wind (dang! I wish I had it before my drive to Albuquerque in 50 mph winds last Thursday), and I swear my mileage increased when I took it out for a drive this weekend.

Thanks Brian...fantastic item! The guys at my Toyota dealership were suitably impressed and want to know my impressions...hopefully more business will be sent your way.

As for the cost...I think it is well worth it considering what I will pay for a new outfit...the BT Stiffening Plate is obviously made to last the life of the vehicle and then some! (I had the techs at the dealership give me the stock plate back so I could remove the BT brace and reuse the brace if the car gets totaled or I upgrade to a new Prius in a few years (assuming Toyota doesn't solve the problem).

 

<div class='quotetop'>QUOTE(gilahiker @ Apr 10 2006, 03:44 PM) [snapback]237650[/snapback]</div>

My dealer wouldn't touch it. They only install what they sell.

 

You must have read my mind!! Actually we have had a lot of people ask if we could supply the torque wrench so I just purchased a large quantity to have on hand. Look for it in the Prius Chat store soon!!


Thanks!!

Brian
BT Tech
305-652-3115



<div class='quotetop'>QUOTE(windstrings @ Apr 10 2006, 02:14 AM) [snapback]237415[/snapback]</div>

 

<div class='quotetop'>QUOTE(BT Tech @ Apr 10 2006, 08:04 PM) [snapback]237804[/snapback]</div>

OOOps.. Too late for me... but I would recommend it if you don't have one. Just to find one at a reasonable price is a chore.

 

<div class='quotetop'>QUOTE(Catskillguy @ Apr 10 2006, 04:48 PM) [snapback]237763[/snapback]</div>

Too bad...my dealer said they do this for lots of folk who want stabilizers put on their cars. Maybe it's because I live in a small town in SW NM...

 

<div class='quotetop'>QUOTE(gilahiker @ Apr 11 2006, 07:14 PM) [snapback]238278[/snapback]</div>

My Dealer torqed mine for free with my first oil change.
They liked it.

 

Has anyone done a blind study of this thing? Practically every post says it works, but I'm a skeptic. How can such a small piece of aluminum make the car handle so much better?

It's obvious that the original Toyota plate is designed to prevent lateral movement from left to right across the body. OK, it's also obvious that the BT plate can easily do the same.

But to prevent cross torque, diagonally across the car, I would think that the plate would need to be significantly larger front to back, like a big square. But it's not. I would also think that it would need to be secured corner to corner. Again it is not; it uses the same holes as the factory plate.

I just can't see how something with roughly the same surface area, AND secured at the same mount points can affect torque across 106 inches of wheel base. Someone explain the engineering behind this. Please!

If I buy one and do a blind study, who will buy my plate after I decide it doesn't work? Are you BT guys willing to refund my money if I ship it back?

 

<div class='quotetop'>QUOTE(pocketpenguin @ Apr 11 2006, 08:18 PM) [snapback]238395[/snapback]</div>

Exactly what I was asking long ago.

 

<div class='quotetop'>QUOTE(pocketpenguin @ Apr 11 2006, 08:18 PM) [snapback]238395[/snapback]</div>

I know you're from Missouri, but no one's going to "show you" more than they already have. Have you seen even one post from someone who bought it and says, "it doesn't work?" I haven't.

Judging from the interest and the number of people who swear by them, I don't think you'd have trouble selling it in the "for sale" forum here on PC. But I don't think you'll be selling it.

Yes, it would be nice for someone to do a perfect double-blind controlled experiment and post the results in the Journal of Irreproducable Results. But it isn't going to happen. Truth is, everyone who buys it and puts it on the car says "holy sh*t this thing works great!" and it never comes off again.

Or you can just waste $160 on five pizzas and beer and drive the same old mediocre-handling car you have now.

 

<div class='quotetop'>QUOTE(pocketpenguin @ Apr 11 2006, 11:18 PM) [snapback]238395[/snapback]</div>

I've have the BT plate and consider myself more sensitive to car handling than most.

The BT plate did change the handling, and IMHO, for the better. It reduced understeer in low speed turns, it reduced the pitching in sharp low speed turns, and improved stability in high speed turns. However, the improvements are not noticable unless driven above 6/10ths.

It's been reported that Sigma Automotive's front lower suspension brace helps to reduce tramlining and I have one on order. Being a JDM container freight item, it will be another month before I see it.

Also, Sigma Automotive's rear lower brace looks much more substantial the the BT brace... I'm still having trouble accepting the price.

YMMV, Brian

 

<div class='quotetop'>QUOTE(pocketpenguin @ Apr 11 2006, 08:18 PM) [snapback]238395[/snapback]</div>

i think you are asking a bit too much. working in customer service, i talk to unhappy and unreasonable people every day. if you are that uncomfortable with the purchase, why are you stressing it?? dont do it.

you say you dont understand how it works. well what do you understand? what is your background? what is your qualifications? do you have any training in this field?

from my point of view, real customer feedback is gold to me and i will take that over any kind of "expert" testimony (pay me enough and i too will say anything) any day.

do you think none of us know what we are talking about?? or maybe most of us are happy or willing to settle with very small improvements? or do you think we are saying the plate works because we dont want to be the first one to report that we werent sophisticated enough to notice the difference?

 

The plate definitley works.

My Prius feels MUCH more tight and almost easier to drive.

 

I didn't mean to offend anyone, though I figured some people would be.

I don't think it is too much to ask a vendor to explain why/how their $160 product works when it isn't patently obvious. I haven't seen any explanation of it on the BT sales page, so I figured I'd ask here where people were talking about it.

I understand that a LOT of things are sold based on subjective opinions and not on hard facts. I buy products based on facts or rigorous reviews. I haven't seen that here. My qualifications? I wasn't aware that I needed any qualifications to ask questions here. That said, I have a background in journalism, engineering and computer science. In the words of a famous radio show "I have a master's degree, in science!" (laughing at self)
I am NOT a mechanical engineer, but my friend who IS a mechanical engineer says he doesn't see how the plate could produce a dramatic change as many here have described. But then we didn't design the Prius, so just because we don't know, doesn't mean it doesn't work. I'm just asking if someone DOES KNOW how it works.

OK, it is a good sign that there are few if any people who say it doesn't work. I'll give you that. But in the face of many threads of skepticism, I would think that the manufacturer would step up when asked (clearly they monitor these threads). I have zero doubt that the plate is sturdy and well built. In fact, it looks more sturdy that the underside of the car to which it is attached. I read one thread describing the Prius as a piece of paper curved over and floppy and the BT plate is akin to putting that paper on a surface so that the edges are stable, thus the entire piece of paper becomes more stable. Like I said, I'm not an engineer, but I would think that if the car was that flexible, it would need a heck of a lot more than a 6x18 inch wide piece of aluminum to keep it from flexing.

I see the positive feedback, assume it is legitimate and made by folks who are entirely honest, well intentioned and believe exactly what they say. But, you must admit that the feedback appears to be entirely subjective, not objective.

Please take no offense because none is meant. If this plate was designed by my best friend and he was a super smart engineer, I'd STILL want him to explain how it works. Being curious and skeptical is in my nature.

When I read an ad that says "tired of this problem, then buy this thing and your problems are solved" (paraphrasing the BT page on this site) then my natural question is, "Oh yeah, how exactly will it do that?" When a company makes a claim that "our product will solve this problem", it is often accompanied by a "or your money back." But there is no mention of a satisfaction guarantee here. If the plate was sold at the local auto parts store, I could at least return it for a refund. But no, it's being sold on the Internet with apparently no warranty expressed or implied. Hmm, I think skepticism in that context is quite natural. Personal shortcoming on my part? Perhaps, but it has served me well so far.

Why am I stressed about this product? I'm not. I'm stressed that my almost perfect Prius is not perfect. Its handling at high speed with wind sucks compared to the 5 cars I've owned in my life. I'd like an easy way to fix that, my life experience has taught me that "easy fixes" to complex problems are VERY RARE.

Why don't I buy the plate and if doesn't work sell it on the forum? Because, I could NOT in good conscience sell an item that I didn't think worked as described.

 

Don't get the plate. Your Prius will keep driving like it does. No pontificating will ever convince you. There is no OBJECTIVE proof of the performance of the BT plate. To obtain that proof you would need to spend staggering sums on test stands, finite-element modeling, and more.

How did Brian design it? He makes chassis stiffening parts for Corvette race cars. He "felt a need" (literally) in his Prius for a stiffer chassis, which was easy for him with his long experience in chassis tuning. He found an existing link in the critical location (which he knew was critical from his experience with other cars) and made it stiffer. It worked. Folks wanted to buy it. A business was born.

The ONLY PROOF THAT MATTERS is... does it work for YOU or not. No one is going to fund a study so you can be assured your $160 isn't wasted. So... just don't buy it.

Problem solved!

 

Hi Pocketpenquin,

I am not affiliated with BT, other than to be a satisified customer of the Prius Stiffening Plate. While others below tend to refute this with their observations (indicating improvement in static load conditions), my observations are that the plate acts more like a vibration dampener.

Vibration is one mechanism where a very small mechanical change can cause a great response change.

What I believe is happening is the vibrations are so quick in the Prius chasis, that one cannot readily feel them through the seat, but the car still darts back and forth in response to them. With the plate, the vibration is damped down to a half cycle at a rate one can easily feel and drive in reaction to. This is what I concluded after many strong wind gust impulse side loads at highway speed on a particularly gusty day a few days after installing the plate. What I felt I realised I had felt before, but at a much higher rate, but only after having installed the plate. With time I am confident I would have been eventually been able to detect the signal of these vibrations, without the plate, but I had only had the car 1 month before installing the plate, and was too busy thinking about driving the car. I think the plate damps chasis vibrations and tunes the vibration natural frequencies to a sufficiently low frequency that its easy to control the car when it experiences high side loads.

Why is the Prius like this? Without a FEM (Finite Element Modelling) Analyst and a few months of his/her time, its hard to say. What is different about the Prius? It has a tall sides for its length. It has glass in the gusset zones front and back. It has a mostly horizontal hatchback on a tall chasis. These are the clues that would probably be investigated.

 

actually if you do a search you can find evidence. when the plate was first introduced, it was sent to a lab where stress tests were made on the plate and measured. there is data (if you can understand the technical jargon) available.

also, the plate although it mounts to the same bolts is recessed and fitted to the main bars it attaches too. it is basically notched so it adds rigidity that the original plate cannot by aligning itself with the entire width of the plate at each end.

 

Nothing scientific here, just my observations.


One particular exit off the NYS Thruway, I shut the cruise control off at the same point approaching the exit & coast into the cloverleaf turn. I made a point several times to 'take in' feel and note the handling before I installed the plate.

After the plate, doing the same exit routine, there was significantly less chattering over the rough road surface and the car was more solid, upright on the turn.

Again, nothing scientific or blind study, just a positive observation. Could I have lived without it?? Yes, because I am used to driving old cars, so the handling of the new Pri was fine. Is it better with the plate, yes IMHO.

 

<div class='quotetop'>QUOTE(pocketpenguin @ Apr 11 2006, 10:18 PM) [snapback]238395[/snapback]</div>

disclaimer: I bought one and noticed a marginal improvement in high speed, banked freeway turns. (knuckles don't lie!) I can't attest to ordinary cornering improvement and I haven't had a chance to drive at high speed in high winds, yet. Was it worth it? Could new tires have improved handling just as well? Maybe.

However, what you are asking is difficult to answer. Any explanation, short of sophisticated FEM analysis would amount to hand-waving. So here goes: given the geometry, its seems clear to me that the neither the BT nor OEM braces would impact torque or flex around the vertical or transverse axes. The location seems designed to prevent twisting in the longitudal axis. That is, the front and rear rotate is opposite directions or are torqued to different amounts which I believe is what you get in turns since the force is not acting through the center of gravity if the body is not stiff. The front wheel drive digs in and the rear is flopping in the wind. You're right that diagonal braces would be best but aren't practical nor probably necessary. I could probably twist the stamped steel OEM brace with a vice and screw driver. Toyota probably spec'd them at $.10 ea. The BT brace is another matter. The CNC webbing isn't just about weight reduction. Note the diagonal bracing. How much does it impact torque at the car extremes? You got me. Maybe we can measure the rear deflection while hopping on the front fender! But its hard for amateurs to interpret even sophisticated static measurements in terms of dynamic handling.

Test drives! Sure, anecdotal testimony by consumers is pretty worthless to a skeptic. Elsewhere you mentioned (double?) blind testing. What's the measurement? Driver testimony? How do you control for wind, temperature, traffic, whatever. A better test would be maximum speed before spinout on a marked course. But I'm not that good of a driver.

Hope this helps.

 

ya its hard to really quantify a "feeling" but i never had major handling issues before the plate. never felt uncomfortable with manuvers, never had the wandering issues a lot of people report here so dont really know that this plate would address that.

in fact UNTIL i installed the plate i couldnt put a finger on any issues. but after the install it was plainly obvious that the Prius' center of gravity now seems to be lower, there is less body roll on curves. before the plate, there was a sense of "top-heavyness" i was unaware of. but after the plate, the car seems to hug the road more. obviously its not. the center of gravity is the same. the plate simply stiffened the flex of the frame and it is noticable.

 

Great post, Ron. Thanks!