[MOC] Subaru WRX STI W/ Instructions

[Touc4nx]

After 9 month of work, I present the completed version of my latest Moc, a 2019 Subaru WRX STI

It features : 

• AWD, with lockable central differential
• 6+R Sequential gearbox
• Fornt McPherson Suspension 
• Rear double wishbone suspension, with anti-roll bar
• Working fake boxer engine
• Opening doors (front one with handle)
• Opening hood (or bonnet)
• Opening trunk
• Interior with detailed dashboard
• Decorated engine bay

Render of the gearbox :

Full driveline

The belly shot

The interior, with some detail, such as aerations.

Engine bay, made to look as close as possible to the real one :

 

 

It can also be built in white, with some minor adjustments.

I also created Instructions for it. The instructions are made for the black one, but can, with minor adjustment be used for the white one.
The instructions are 1218 pages long, handmade with Stud.io 2.0.
You can download a sample here.
Or look down here.

You can Buy the instructions on Rebrickable.

https://rebrickable.com/mocs/MOC-38243/Toucanx/subaru-wrx-sti/#comments

And of course a video :

 

 

I Hope you like it.
If you have any question, don't hesitate, I will try to answer quickly.

 

After this line, starts the WIP thread.

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Hi everyone,

It's been a long time since I haven't posted on this forum, but today I would like to share a new project that I have started not so long ago.
It's a Subaru Impreza WRX STI car that I will make.

 

The list of what I will put in the car is the following :

• Awd
• Boxer 4 engine
• McPherson suspension for the front wheels
• Indépendant double whisbone for the rear wheels
• Lockable central differential
• 5 speed sequential gearbox

I searched a bit for 5-speed sequential gearbox but I didn't found any. So I took a 4-speed gearbox design by @Rage_Hobbit (found there) and I added a 5th speed.
Here is the result :

 You can download the .lfx. Note that you are supposed to place rubber band linking the orange pieces to the black one under the blue triangle.
 I have already made the boxer engine and most of the chassis. It will use these wheels :

It's the one that are used in 42077 rally car.

However I ran in a problem, it seems that the gearbox can not support the force involved in the transmission. The gears do a lot of skipping noises (doesn't sound healthy for the pieces). So I wanted to know if anyone knew a reliable 5-speed sequential gearbox / a 5+r sequential gearbox.
That's it for today. More updates coming soon.

Edited March 25, 2020 by Touc4nx
Finished MOC

[Didumos69]

1 hour ago, Touc4nx said:

So I wanted to know if anyone knew a reliable 5-speed sequential gearbox / a 5+r sequential gearbox.

I know @Paul Boratko's 5+R AWD transmission. I modified it to include a center diff lock in this model. It surely doesn't slip, but it's not free of friction.

[letsbuild]

This seems like a promising project, looking forward to some IRL progress!

[Touc4nx]

Little update : I just looked online and found that the gearbox is supposed to be a 6 speed gearbox. So I will try to find a 6 speed design.
But thanks @Didumos69 for the idea of a 5+r gearbox but I think I won't use use it.
 

[Touc4nx]

Update : Some IRL pictures
Front suspension : McPherson with negative caster angle

Without wheels

And a view from the bottom of the car :

You can see the central differential in the middle of the picture.

[Lakop]

Are you using the larger springs at the front and rear ?

H

[Touc4nx]

4 hours ago, Horace T said:

Are you using the larger springs at the front and rear ?

H

No I won't because I don't have 4 of them 
But the travel of the suspension is the same.

[Touc4nx]

Here are some new pictures:

• I added a working 6+R gearbox
• I adde an anti-roll bar on the rear suspension

The gearbox ratios are :

rear : 1 ; 0,375

forward :

• 1st : 1 ; 0,12
• 2nd : 1 ; 0,2
• 3rd : 1 ; 0,216
• 4th : 1 ; 0,36
• 5th : 1 ; 0,6
• 6th : 1 ; 1

The gear changing mechanism is behind the rear axle, and just need to be linked with a motor.
I use two 90° steppers (by @Didumos69) because they are compact and reliable. (it's this one, only the left part of it.)

The anti-roll bar is in pink in the render 

And just for fun a render of the full car as it is built currently in digital version.

 

[Touc4nx]

Quick video to show the gearbox in action.
(it's better to look at the front wheels to see the speed differences)

[Lipko]

I seriously doubt that the front suspension will hold the weight. Those yellow thin liftarms on the chassis will break.

[SNIPE]

Hi,

Can you share the digital file of your 6 speed gearbox with the orange gear shifters.

I need a 7 speed gearbox for my MOC so could use this as a starting point.

Thanks

[Touc4nx]

On 4/18/2019 at 5:55 AM, Lipko said:

I seriously doubt that the front suspension will hold the weight. Those yellow thin liftarms on the chassis will break.

For now it holds it but I agree that later it might become a problem. So I will probably modify it for a stronger setup.
 

 

On 4/18/2019 at 6:37 AM, SNIPE said:

Hi,

Can you share the digital file of your 6 speed gearbox with the orange gear shifters.

I need a 7 speed gearbox for my MOC so could use this as a starting point.

Thanks

I put it on bricksafe : .lfx there is the gearbox file and the complete file. (blue 1L Liftarm stands for the blue clutch gear and the orange gear stands for the gear shifter.)
However it might be hard to turn it into a 7 speed gearbox, as it is more like a 3+R gearbox, linked with a 2 speed gearbox.

[M_longer]

Conisder using a direct shaft from XL motor to the fake engine, without passing the drive trough gearbox, pistons will move at the same speed on any gear.

[Didumos69]

Going by the renders of the chassis I strongly advice you to use more lengthwise beams running through the chassis. Not only at the bottom but also higher up. And make a strong column running in-between the seats. If you don't do that, then I expect a lot of bending under the cars own weight with possibly squeezed frictioned gears as a result.

[Touc4nx]

Some updates.
I redesigned the gearbox, it's now way smaller, more compact and uses less gear.
Gear ratios are still the same.

The gearbox is now 12 x 13 x 5 (including all gears, but without the shifting mechanism.)

Input is in Green

Output is in Purple

Gear shifting is in Yellow

You can download the file here. (it's a Stud.io file)

[Touc4nx]

It's been a long time without any progress but today there is a lot.
I made the hood and the front

 

There is led light and you can open the hood ( I still have to make the engine better.)

I also reinforced the gearbox as some gear were skipping under high torque.

It's a bit messy with all the cables but now every motor is in place. It means that I can change speed, lock central differential, drive and steer the car.

That's it for today.

Edited June 21, 2019 by Touc4nx
Manipulation error

[nico71]

This is a great work.

But you should definitively start by designing the bodywork and not the chassis. Juste make a fake chassis for the proportion (whee, wheelbase, width length etc.) and then make the bodywork. When the bodywork is perfect at your eyes, you can make the chassis, and fit all you want (and can) inside.

Because, as I see the project, I see the chassis is well done and very sophisticated, and the bodywork is not at this level of detail, a bit too bulky. So I advice to start with the bodywork to focus the effort on it and then made the chassis.

It is not a hard criticism, just a tips to have a bodywork which is a good, as the inside.

 

[Touc4nx]

I understand your point, however I don't see how I can apply your advice as I need a chassis with at least working suspension and steering to design the bodywork, especially the wheel arches...
And I almost always start a Moc with a list of functions I want in it. If I do the bodywork first, I'm scared not to be able to fit all mechanism.

( And bodywork is my weak point  )

[KD123]

Nico - when you design your cars, do you start with body work and then work inwards to the chassis or do you start from the chassis out? 

Touc4nx - there is an old spoiler part that I think might look good for that hood scoop.  Keep up the great work.

Edited June 22, 2019 by KD123
Consolidation of posts.

[Touc4nx]

Is that this part you're talking about ?

[T Lego]

I realy like what you are doing here. The gearbox looks great! Like Nico said, the bodywork looks a bit bulky. The bonnet is a bit too flat and I think It should be inclined more when I look at the counterpart. Good luck!

[Touc4nx]

37 minutes ago, T Lego said:

The bonnet is a bit too flat and I think It should be inclined more

That's true, and by doing some comparison between the real car and mine, I realized that the hood is too high, it should be two stud lower.
So I'm searching for a way to do a smaller McPherson suspension. However I keep having a problem : the wheel and the wheel hub are pushed outside... 
So if anyone has a design for small McPherson suspension, I would gladly take it.

[nico71]

I personnally start to make a fake chassis with only the correct dimensions, wheel base and steering. And Then I design the bodywork. When I am satisfied with the bodywork (which can be before the end of design) I design the chassis. In this way, the bodywork is never bad compare to the functions :)

I start to make like that since the big Citroen 2CV because the bodywork was a huge challenge. And making a complete chassis and then can't figure out the bodywork would be losing my time.

[Gray Gear]

I'd use frame pieces instead of panels for structure, they offer way more fleyibility, and are way easier to use to achieve good stuctural integrity. I dont want to insult your work, but imo everything looks kind of fragile. The front bodywork looks pretty good though, the hood scoop is something I would try to improve tho. Put that hole in the hood, please .

[Gray Gear]

1 hour ago, nico71 said:

I personnally start to make a fake chassis with only the correct dimensions, wheel base and steering. And Then I design the bodywork. When I am satisfied with the bodywork (which can be before the end of design) I design the chassis. In this way, the bodywork is never bad compare to the functions :)

I start to make like that since the big Citroen 2CV because the bodywork was a huge challenge. And making a complete chassis and then can't figure out the bodywork would be losing my time.

Doing the Bodywork first is probably a good Idea for smaller Models like your amazing S2000 that have relatively simple internals. But for models with complicated functions like Gearboxes and stuff, you sometimes have to design the whole body around these functions. In my Honda NSX MOC (which I hope to upload here soon) I started with the 6 speed manual Transmission and built the whole car around it. There is no way I could have put in such a complicated mechanism in after doing the bodywork.