Which brace?

[jvanzyl]

I've been researching where to get the X-brace that Dev's posted about. They're a bit nebulous but I found a parts number:



A mate of mine knows Japanese so if we manage to find a bunch of them over in Japan, I'll let you guys know.

Man that's totally something I'd want...

Sent from my Moto G (5) using Tapatalk

[Snelbaard]

If I'm able to get just one (which in itself is a big if), I'll look into making reproductions of these, too

I have to say this brace is proving rather difficult to find..

[Snelbaard]

Well it looks like I'm not going to be able to source them from Japan (or anywhere for that matter). I contacted Tom's and they really went above and beyond to contact retailers to inquire if any of them had any braces left. Apparently none did. I checked and I do have some tube that looks really similar to what the Tom's brace is made of. I'll fire up my welder and see if I can cook something up.

[edit: If all goes well, I'll be able to make an announcement the day after tomorrow]

[Snelbaard]

Right so I've managed to find and purchase this lot in Japan:



It cost me an arm and a leg but I'm well chuffed, and it means that I'll be able to make new ones that are properly true to the original. I'll also make a version that will work with the Moroso pan.

Sadly there's still a looooong wait untill the package arrives.

[shnazzle]

Right so I've managed to find and purchase this lot in Japan:



It cost me an arm and a leg but I'm well chuffed, and it means that I'll be able to make new ones that are properly true to the original. I'll also make a version that will work with the Moroso pan.

Sadly there's still a looooong wait untill the package arrives.

Success! Very nicely done.
Can't even imagine how much it cost....

[StuC]

That's some next level perseverance for some bracing. Justsayin'

[1979scotte]

Unfortunately half of that won't fit on mine because of the V6 but would love the rest.
Well done.

[tets]

This is really interesting me and very very well done on sourcing that lot!

[Snelbaard]

Thanks guys! The TRD front strut bar is no use to me as my car is LHD and I recently got one anyway. That, as well as the Cusco breast plate will probably be sold here when everything arrives. Even though I also sell, you know, far superior ones

[1979scotte]

Just being silly ignore

[jvanzyl]

wow! You managed to get the Toms X brace!
Nice one...
I'm looking forward to the reproductions of those!

[Chriss]

That is an impressive amount of bracing, I have a TRD one ordered from Toyota, hope it is a right hand drive one and I did not mess up the serial number. I will be interested in what you make from these.

[Dev]

 
Good to see that you were able to get the Toms rear under brace.

 Just to add a little more desire for this brace, there is this road with a sharp low speed corner where I can kick the rear out if I force it and loose traction in the rear smoothly at the same time I can punch the accelerator pedal and spin out the rear to bring the car back in line. 
 Before this brace the rear would be swaying  like fine steps.

[Petrus]

The two for my insight on vehicle handling most insighful books are

Motorcycle Design and Technology: How and Why  - Gaetano Cocco 
Motorcycle Handling and Chassis Design: The Art and Science - Tony Foale

Although about more complex single track vehicles, all is applicable to cars. Even in motorcycles rigidity is a double edged sword.
A degree of flex matched in harmonics is ´the art´ mentioned.

Concerning the MR2 Spyder it strikes me how much braces are availeble and no less than three types of which are dubbed the most important, with Dev´s spacers thrown in as a bonus important stiffner.
Makes me wonder where the balance is. Even more so if we add stiffer springs/dampers into the equasion.

If the two above mentioned books teach óne thing than it is; it is all connected. Change one thing and the effect of the rest changes too.

Note that TRD was quite conservative with their mods. in the Sportivo kit. Even though they stiffened the springs a bit and also both arbs, they only!! added a front strut brace whereas they did take the trouble for the dog bones.

Bear in mind that adding braces reduces chassis compliance which is also beneficial for road holding on less perfect tarmac or a narrow twisty road with a pronounced crown to give but two examples.
It is not all about crisp turn in. Compliance is at least as important, with that compliance being balanced; predictable.

I suspect we once again get into the area made obtuse by conflicting requirements, use, circumstances, matching or not other mods. The latter totally is the flex and harmonics; the art.
Remember the issues Schnazzle created by fitting Dev´s door braces; even the driver is part of the harmonics. Way less so than on a motorcycle but still a part.

Note that I am nót writing that braces are useless. I ám writing that they need to fit in the whole with that whole fitting the use.

[Beachbum957]

Having built motorcycles for professional racing, I can say that chassis technology for 2 wheels is VERY different than for 4.  Only a few things apply, such as the impact of damping curves on keeping the tires on the ground (somewhat), but when a motorcycle is leaned over, at least some of the suspension is from chassis flex.  Moving the "center" of flex front or back can have a huge impact on handling.

If you want to learn about chassis design for cars, stick to books on car chassis dynamics, particularly race car technology.

[Petrus]

Having built motorcycles for professional racing, I can say that chassis technology for 2 wheels is VERY different than for 4.  Only a few things apply, such as the impact of damping curves on keeping the tires on the ground (somewhat), but when a motorcycle is leaned over, at least some of the suspension is from chassis flex.  Moving the "center" of flex front or back can have a huge impact on handling.

If you want to learn about chassis design for cars, stick to books on car chassis dynamics, particularly race car technology.

Of course there are fundamental differences; we are comparing cone steering with perpendicular. Nevertheless quite a lot is very much applicable.
When a car corners the centrifugal forces make the chassis flex and at least some of the suspension...  That suspension by chassis flex is indeed the crux of my observation.

[Petrus]

Took me some time to find it again but here a photo illustrating why the Matt TTE replica was a total NoNo for me.
Snelbaard´s copy is a neat compromise for me: Just a tad more rigid than Toyota intended with the two OEM braces, lightweight end no loss of ground clearance.

[shnazzle]

Took me some time to find it again but here a photo illustrating why the Matt TTE replica was a total NoNo for me.
Snelbaard´s copy is a neat compromise for me: Just a tad more rigid than Toyota intended with the two OEM braces, lightweight end no loss of ground clearance.

Fact of the matter is, the TTE brace really does work. 

What I'd like to know is how the Snelbaard Corky replica compares. 
@jvanzyl said that adding the Snelbaard to the TTE made a big difference. So I wonder whether its overriding the TTE, or complimenting it

[Petrus]

THe TTE design shoúld work as it x-braces the outer corners of the floor pan.
You can see that it is mostly aimed at working in a flat plane; it keeps the floor ´square´.
The ham question is whether it is worth the weight penalty and for mé the loss of ground clearance is jaw dropping.

The Corky/Snelbaard connects the footwells and will have an effect of resisting torsion of the central spine.

[shnazzle]

THe TTE design shoúld work as it x-braces the outer corners of the floor pan.
You can see that it is mostly aimed at working in a flat plane; it keeps the floor ´square´.
The ham question is whether it is worth the weight penalty and for mé the loss of ground clearance is jaw dropping.

The Corky/Snelbaard connects the footwells and will have an effect of resisting torsion of the central spine.

My car is lowered a fair bit and I can honestly count the amount of times I've dinged the TTE brace on one hand in about 4 years

[Carolyn]

THe TTE design shoúld work as it x-braces the outer corners of the floor pan.
You can see that it is mostly aimed at working in a flat plane; it keeps the floor ´square´.
The ham question is whether it is worth the weight penalty and for mé the loss of ground clearance is jaw dropping.

The Corky/Snelbaard connects the footwells and will have an effect of resisting torsion of the central spine.

My car is lowered a fair bit and I can honestly count the amount of times I've dinged the TTE brace on one hand in about 4 years

I've never grounded mine.  Mine car isn't lowered, but I do live in the pot-hole capital of the entire universe!  I was very sceptical of this brace, but I got one so cheap, I simply had to give it a go. It did make the car much smoother over the bumps.  I wouldn't be without it now.

[Petrus]

I am happy to read that you can live without a downside and thus simply enjoy the stabelising effect on the floor.

I live in a different part of the world. Not only with 300 days of sun/year but also mostly empty well maintained B-roads that have generally no smoothed off/on at road side stops whether mirador, picknick area, restaurant or most side roads.
Because it cán poor down rather hard here and more importantly it is a moutainous country, the roadside drainage is quite acute, meaning that accesses to driveways and such usually have a fairly deep ´ditch´ meaning that getting back onto the main road is a challenge with limited ground clearance.
Toutched ground Sunday underway to Jerez getting back on the main road from a roadside restaurant parking lot. That was going carfully and at an angle.
Even grounded it twice with it higher on the springs than OEM.
The TTE design would make my car .... useless.

The rural zone where I live is more extreme still because much of the network of local roads is unmetalled. Well maintainded, that is not the issue but the connections with tarmac are basically, literally unsurmountable with the MR2.
Thé most popular mod to not SUV cars here is ... a metal sump guard.

Bottom line is that it is driver´s heaven here but beware of the ground clearance when going off the black stuff.

[1979scotte]

THe TTE design shoúld work as it x-braces the outer corners of the floor pan.
You can see that it is mostly aimed at working in a flat plane; it keeps the floor ´square´.
The ham question is whether it is worth the weight penalty and for mé the loss of ground clearance is jaw dropping.

The Corky/Snelbaard connects the footwells and will have an effect of resisting torsion of the central spine.

My car is lowered a fair bit and I can honestly count the amount of times I've dinged the TTE brace on one hand in about 4 years

You don't scrape on stock suspension.
With lowering springs you will only catch on separated speed bumps.
With coilovers on the V6 with a 40mm or more drop it would catch on everything which is why I took it back up to around 25mm. Lowering more than 30mm is just stupid on a road car IMHO.

[Petrus]

Lowering more than 30mm is just stupid on a road car IMHO.

Have you seen/measured by how much the TTE brace ´lowers´ the car?! That was my point. That ánd the art of the compound flex/harmonics of suspension and chassis. One of the things I like so much about the car is how .... euhmmmm... expresssive it is about even small. Like Dev´s door braces leading to various percepcions ánd illustrating that the driver too is part of the system. Lóve it.

[1979scotte]

Lowering more than 30mm is just stupid on a road car IMHO.

Have you seen/measured by how much the TTE brace ´lowers´ the car?! That was my point. That ánd the art of the compound flex/harmonics of suspension and chassis. One of the things I like so much about the car is how .... euhmmmm... expresssive it is about even small. Like Dev´s door braces leading to various percepcions ánd illustrating that the driver too is part of the system. Lóve it.

Yes as I've had 2 of them and much prefer the car with than without.
Sorry if that disagrees with your science.