Flex-Free Cornering. Mishimoto Fiesta ST Trunk Brace R&D

[mishimoto1]

Wow, this is a really slick design. Keep up the great work, Mishi!

Thanks for taking a look Gabos!

-John

 

[obsandrew]

A buddy just sent me the link from the [MENTION=1848]mishimoto[/MENTION] website. I've been waiting for something like this!

 

[WhiteFords]

Hey Mishimoto, how about a front tower brace? I like what you are doing on the trunk brace, but I feel I need the stiffening in the front of the chassis as well.

 

[mishimoto1]

A buddy just sent me the link from the [MENTION=1848]mishimoto[/MENTION] website. I've been waiting for something like this!

Great! Nice to hear the word is making its way around. We should have an additional update pretty soon.

Hey Mishimoto, how about a front tower brace? I like what you are doing on the trunk brace, but I feel I need the stiffening in the front of the chassis as well.

Thanks for the recommendation! We've had a few of our contacts come forth with front suspension ideas and we definitely want to tackle those projects. We just pulled an ND Miata into our shop last week so that is pulling some hands from the Fiesta. Once we open up some time, we should be able to launch a couple of additional projects on the Fiesta.

-John

 

[ogsigh]

I'd like a red or black one and a gold intercooler would look neat

 

[trsandrew]

Is floor flex really an issue here? Maybe when I have 18x10s on slicks on all four corners sure, but on the street?

 

[WhiteFords]

My 5k mile FIST has more little rattles and funny noises on rough pavement than an old stagecoach. My car needs all the chassis work it can get.

 

[trsandrew]

and my 6K-mile Fiesta which I've only had 3 months now (since 64 miles) is perfectly fine despite tons of hard curvy roads. Floor flex isn't your issue.

 

[mishimoto1]

I'd like a red or black one and a gold intercooler would look neat

Thanks for the input!

Is floor flex really an issue here? Maybe when I have 18x10s on slicks on all four corners sure, but on the street?

I think we will be very surprised to see the benefits of this particular component. We can't make any claims quite yet, but once we perform some testing we should be able to provide a more accurate description of the improvements. Several of our information sources have noted a big improvement with a stiff brace in this location. We shall see!

My 5k mile FIST has more little rattles and funny noises on rough pavement than an old stagecoach. My car needs all the chassis work it can get.

As mentioned by Andrew, I am not so sure extra bracing is going to help with this.

-John

 

[mishimoto1]

Time for a project update!

Flex-Free Cornering. Fiesta ST Trunk Brace R&D, Part 2: Prototype Completion

We left off development with a neat look at our first prototype, when we determined the shape and path of our brace and printed out mounting brackets for each side of the piece. By using specific angles with our square material, we were able to avoid modification of the seat mounting bracket, retain rigidity, and provide a bar that is easily hidden by the rear tray.

Our last image showed our fabricator tacking together the material. Below is what we ended up with.

Prototype Fiesta ST rear strut brace installed

We then installed the floor panel mounting covers.

Prototype Fiesta ST rear strut brace installed

Let’s take a closer look at how the plastic interior components sit with respect to our brace mounts.

Prototype Fiesta ST rear strut brace installed

As you can see, the height of our mounts will prevent use of the lower mounting position for the rear tray. We want this bar to allow the tray to fit in both the lower and upper positions, retaining all intensions from the factory design.

First Prototype Adjustments

We typically go through a few prototype iterations as we work out minor bugs. Time spent and the collective brainpower of our team truly shows in the final product.

After much consideration, we modified the mounts to lower the profile. Doing so allows the rear floor tray to sit in the lower position, maximizing trunk space.

Prototype Fiesta ST rear strut brace installed

As you can see, we’ve trimmed the height and adjusted the shape slightly. This should give us the space needed to fit the floor in both positions.

Check out another shot of this prototype iteration.

Fiesta ST parts development

Looking good!

How could we make it better?

This question is constantly tossed around during product development. Guess what? We found one more feature to build into this component.

One of our quibbles with the stock tray fitment had to do with stability. In the lower position, the rear of the tray is unsupported and not exactly balanced. Not a big deal, but we figured out an easy way to support the tray and balance it perfectly for when you are loading up the trunk with groceries, track tires, friends you don’t like, toilet paper, etc.

We started by bending a couple simple brackets.

Fiesta ST parts development

For ease of installation, these will need to be removable. We installed two rivet nuts into the bar to thread our bolts into.

Fiesta ST parts development

Fiesta ST parts development

Bolts are pretty inconvenient though, especially if this piece needs to come in and out easily. Enter the almighty thumb screw!

Fiesta ST performance parts development

Check out both of these brackets in place.

Fiesta ST performance parts development

Once the rear tray is in place, most of the bracing and brackets are covered, although the thumb screws are still accessible.

Fiesta ST performance parts development

Fiesta ST performance parts development

More importantly, the tray is well supported in all areas with these additional brackets.

Function: Check!

Form: Check!

With the tray in the upper position, the brackets can be removed and the brace is completely hidden.

Coming Up!

A prototype with plastic portions is certainly not going to do us much good for product testing. We will be working up a full metal piece with all our new features. This will allow us to conduct test fitting and on-road product testing.

Check back soon for a look at our functional prototype. Keep an eye on our blog for more exciting Fiesta ST product development.

Thanks for reading.
-John

 

[CanadianGuy]

I see some orange! Great job. I wonder if the extra brackets could also be height adjutable to add extra support when using the floor at its upper position. Not a necessity but add beefyness.

 

[mishimoto1]

I see some orange! Great job. I wonder if the extra brackets could also be height adjutable to add extra support when using the floor at its upper position. Not a necessity but add beefyness.

Thanks! Our 3D printer material is orange, makes for some flashy prototypes. Interesting idea regarding the height adjustment. When in the upper position, the floor seems to have far better support, but we can certainly take a look.

Thanks for the comment!
-John

 

[Cesso]

Love the design improvements that you have made! A+ product development. Looks like another must have for my car.

Thank you Mishimoto!

 

[mishimoto1]

Love the design improvements that you have made! A+ product development. Looks like another must have for my car.

Thank you Mishimoto!

Thanks for taking a look! I will pass on the appreciation to the engineering team.

-John

 

[BlueBomber]

nice work guys, this is a must have for me.

 

[mishimoto1]

nice work guys, this is a must have for me.

Thanks BlueBomber! As soon as our functional prototype is complete we will post up a few shots.

-John

 

[15Fist3rST]

Another subscription to Mishimoto.. You guys are doing great work. Waiting for the pre-sale!

 

[Batnismo]

Awesome work!

 

[mishimoto1]

Another subscription to Mishimoto.. You guys are doing great work. Waiting for the pre-sale!

Awesome work!

Thanks guys! We have some really neat testing plans for this brace. Our functional prototype is nearly complete and we are pretty excited for the test fit.

-John

 

[mishimoto1]

Project update!

Flex-Free Cornering. Fiesta ST Trunk Brace R&D, Part 3: Functional Prototype and Test Rig

In our last update, we left you with some mock-up prototype pieces that we used to create and refine our Fiesta ST rear strut brace design. Since then, we’ve worked up a couple of functional prototypes to test our ideas for stiffening the rear of this hot hatch.

Initial Prototypes

We constructed two prototypes of this trunk brace. The first prototype is finished in a black powder coat, and we’ll use this unit to evaluate for aesthetics and fitment. The unfinished (“raw”) prototype is going to be used for testing purposes, meaning it will be modified.

First, check out our powder-coated unit bolted into place.

Mishimoto Fiesta ST performance parts

Mishimoto Fiesta ST performance parts

Everything fit nicely and bolted into position as designed. Check out a close-up shot of fitment with the lower tray support.

Mishimoto Fiesta ST parts

With the lower tray in place the bracing is barely visible.

Mishimoto Fiesta ST parts

Although this unit fit well and is extremely robust, we are going to make a couple tweaks. Because this bar is thick and heavy, we need to consider the added weight. The projections near the mounting flange will be eliminated. By trimming this feature, we can reduce the weight of this bar significantly. This portion of the design was in place for aesthetic purposes, so removing them will not impact performance.

Check out a couple shots of our raw prototype before we modify it for testing purposes.

Mishimoto Fiesta ST parts

Mishimoto Fiesta ST rear strut brace prototype

Testing Rig Fabrication

Taking information and experience from our recent Mustang strut bar testing, we will be using a digital linear displacement gauge. This device will record object movement, which we can use to compare movement of the rear of the Fiesta both with and without a brace in place.

First, we cut our prototype in half.

Mishimoto Fiesta ST rear strut brace prototype

Our team needed a method to stabilize this bar during movement to keep the bar from moving in a vertical direction. We devised a piston and cylinder assembly that was machined on our lathe and welded to each cut end of the center portion of the bar.

Mishimoto Fiesta ST rear strut brace prototype

After some precise TIG-welding, our testing setup was complete.

Fiesta ST parts testing

This setup will provide a displacement of the distance traveled as the two sides of the body flex in either direction.

Fiesta ST performance parts testing

This setup will work perfectly for testing the flex on a Fiesta without any bracing. Once that data is captured, we will tack weld steel in place to support the bar as if it were one piece. This will provide the displacement data for our Fiesta with the rear strut brace in place.

Fiesta ST performance parts testing

Coming Up – Testing Data

We have some interesting plans for this testing device. Next time we will explain our plans for testing, conduct the tests, and present our findings.

Thanks for reading!
-John