Stiffen Chassis plate for my 07' Prius

Nicely done! Looks good.

 

First, let me say that looks really nice and you did a great job. But are you sure it will make any sort of difference? I know you have yours and BT-Tech has theirs, I have been looking at it and reading posts on it, and I am not convinced that this is any sort of area that the vehicle can be improved. Are the guys at BT or you thinking that the factory brace flexes?!!! it looks like it would take a lot to flex that thing, I would think that Toyota's engineers knew something when they designed it. I especially find the claim of less cross-wind effect with an upgraded plate to be... well... strange. I probably should have posted elsewhere, but if the Prius whips around after a gust of wind, it is because of its soft suspension not a twist of the chassis. Someone please tell me how a cross wind twists the car's chassis? that makes no sense to me.

 

Haha.. okay. You are just making assumptions. The stock plate can be flexed by hand. The BT plate is 1600x stiffer. There's quite a few threads on the BT plate and it's benefits. The chassis of the Prius is prone to flexing. That's why there are so many braces for it. BT plate is just one of them. Welcome to Priuschat.

 

of the standard can be bend by hand
it stil d's not mean that it wil do this easy
and maybe the selfmade alu plate wil brake but flex a bit more because its alu.

i think plates like these are design for it and you cant just make a bigger one from weaker material.without some calculations.

 

I prefer to have a bigger stiffening plate of any kind instead the Toyota OEM stock plate, knowing Japanese automakers cutting corner on material, specially on economy vehcile like prius. Take a good look under the your prius, every bit of the parts used on the prius looks weak to me.

 

gangpw924,
I think your plate looks good, but I like BT Plate better because it has diagonal reenforcement. It is better for torsional rigidity.
After installing the BT plate, I can feel the difference in the rigidity of Prius body.
This is very obvious when you drive your Prius over railroad crossings or potholes.
However, my roadholding test showed no improvement in lateral g.

 

Hi gang...,

Looks nice.

It would be wise to use some sorta electrical isolation between this plate and the chasis to prevent electrolytic corrosion. Some stiff abrasion and crush resistant plastic film is called for. The amount you need does not cost much, but unless you already have a roll to cut it off from, there is another $30.

If your going to run around on salt treated roadways, it would also be wise to paint your plate.

If you have a benchtop CNC, it would also be easy to machine triangular pockets rather than straight ones, which would stiffen the brace in fore/aft sheer load.

 

I think a lot of the attempts to improve torsional stiffness with the part will be pointless given how close together the mounting points are.

If you could widen the mounting points or add additional ones that would significantly improve torsional rigidity.

 

"of the standard can be bend by hand
it stil d's not mean that it wil do this easy
and maybe the selfmade alu plate wil brake but flex a bit more because its alu.

i think plates like these are design for it and you cant just make a bigger one from weaker material.without some calculations."

Huh?

Must have been sleeping in ESL class?

 

Lots of ignorance going on in this thread. I suggest you read a few more threads before making so many assumptions. The stock plate can be bent by hand. If you can bend T6 aluminum by hand, then you will be a shoe-in for the world's strongest.

 

I did search for more threads on this plate, maybe I missed a few but I didn't see anything that sounded remotely scientific to me. I am not trying to be negative, I am all for a stiffer chassis. But how did this idea come about? How did someone see this as a point of chassis flex? By a hunch or was there some serioys testing done? People make a lot of claims that are not always based on fact, I want to know before I drop $140 on a plate.

What makes me skeptical are that facts that the plate is very short. The fact that most Prius's have a very soft suspension and that you can't really notice things like this when the car is that soft. The claim that it somehow helps in a crosswind makes NO sense to me at all (and frankly I have never even noticed this "problem" on a Prius).

Forgive my skepticism, I am really asking for more convincing input if anyone is willing to give it to me without telling me to go search (if you are, please give me a link because I already searched and found nothing concrete). If it really makes a difference then I am all for it.

 

Are you going to get it anodised to prevent the floor from rusting and use HT stainless steel screws to fit it? Once you add these costs and cost the labour the BT Tech plate looks like a pretty good investment over a home made plate. (depending on your opinion of the need for a stiffer plate.

Material Cost: $35.00
Tools: Benchtop Milling Machine with 1/2" end mill, Air Compressed Sander, Cost to operate??? (Power, tools, wear and tear, machine purchase price, depreciation, floor space etc)
Time: 3 weekend hours (Well I get paid about $28 per hour so that is $97 worth of time)
Make a mistake and throw it in the bin(add $35), if BT make a mistake that is their loss not mine.
What is the cost to anodise and high tensile stainless steel bolts and washers?

I have a BT Plate on my Prius and I think it makes a positive difference. I was fortunate in that I bought my plate second hand but if I wanted the plate I would buy the BT Plate because it supports Prius Chat and looks better engineered to my eye.

HSDP,
I don't think the chassis strength or stiffness has been tested due to the cost and the small market but if your friend told you a particular dish at the restaurant you are eating at was very good would you ask him/her for a scientific analysis to prove it before you ordered? If you don't like the BT plate you can on-sell it and your loss would be less than the cost of a good steak at a reasonable restaurant. A lot of people here who have "eaten" the BT Plate have said it "tastes great".

 

I did a thorough reading of the BT plate thread. There were two tests, one by the manufacturer, having drivers thest the vehicle with and without, and another fellow who tried to measure the flex in the Prius by putting it up on jack stands. My Report:

To be a real member of PriusChat you have to weigh in on the BT Plate. My qualifications:

1. I drive a Prius. 5 months now.

2. I read 40 pages of this thread, including the only two that had any real data, the one by the manufacturer and the one by Allemande, and all the critiques of the data.

3. I am an Evidence Based Medicine-trained physician, so I know something about placebo effects.

4. I have had the BT plate on for about a month now, and have driven it under a variety of conditions. I am not an aggressive driver.

My thoughts:

1. The tests that would really show if there is a difference have not been done.

2. The minimal tests that have been done are a wash.

3. The engineering discussions have not resolved the matter one way or the other.

4. All the testimonies that it makes a difference do not consititute convincing evidence to me. I have been through enough fads (anybody remember blue-green algae?) to no longer believe testimonials, even overwhelming numbers of them, without objective data.

5. In my driving, I have noticed no difference.

Conclusion: NOT PROVEN

I'll keep it on cause it looks cool and is more hassle than it is worth to take off, and besides, maybe somebody will come through with real data some day.

But I would not recommend it as and investment to someone specifically to improve handling. Get better tires first.

 

If you DO drive hard, the BT plate will show it's benefit. It is a better investment than tires since tires wear out, and their handling effectiveness will surely go down over time. The plate is a one-time cost. Depending on how much of a handling freak you are, consider Tom's Rear Brace. It is basically the BT plate on steroids.

 

I have a 2005 supercharged Acura NSX with some suspension parts imported from Japan from the NSX-R model, and I use semi-track tires on this car that is about 3" off the ground and a foot lower than a Prius. I installed several aluminum braces from the R model, and with driving that would be 10X more aggressive than anyone would do on a prius, I notice an ever so slight improvement in the car chassis' responsiveness. This is why I am having a hard time seeing this plate improve things on the Prius, although... the truth is that I just don't know. But then I got in the Touring Prius for the first time trying to see if it really is different, and after 3 seconds and 10 yards I looked over at my girlfriend and said "It's different". Many people (including my girlfriend) probably wouldn't even notice the difference in the suspension if you didn't tell them let alone the BT brace. That doesn't mean it is not there. I will say this... if I get one, I am putting it to a serious test. And I will give a pretty definitive feedback with some data from track testing. I know this sounds kind of ridiculous... this is an MPG machine... but I can save gas by never slowing down around corners.

Thanks for the input everyone, this is a refreshingly mature and polite forum. Can someone point me to a good place for the Tom's braces?

 

You're also making assumptions, and lots of it. First of all, please technical reference your statement that "The chassis of the Prius is prone to flexing". There are many people wanting to make money for car accessories - it doesn't mean they're all necessary, and Prius is no exception. Secondly, the threads on BT plate in this website that are for it have absolutely no scientific basis whatsoever, instead relying on subjective statements from believers.

 

Very nice looking piece !!!
Now, the elite of BT Tech "fanatics" will have some more things to said and to defend Brian's products even more.

 

We've already established your utter ignorance, and stupidity. When I'm really bored, maybe I'll smack you down again. I've got better things to do, like pick my nose. Don't let the door hit your nice person on the way out, troll