[AMS1] 42056 Porsche 911 GT3 RS Crawler 4x4

[Zerobricks]

I decided to open a seperate topic for this beast.

Inspired by Letsbuild's idea to crawlify a Lego set, i decided to go full crazy and try to upgrade the biggest, heaviest and most orange set to date, Porsche 911 GT3 RS.

First thing I built was the front axle, which uses the H frame as a placeholder for bewel gear, so there it no possible way of them to slip:

Those with sharp eyes may notice the gears are not aligned, this was done in LDD development mode, more info soon

The drive than goes directly to portal hubs with 1:3 gear ratio, giving the model 1:5 gear ratio on each wheel.

Front axle also has a servo motor which steers the wheels and powers the Porsche's original steering wheel via a ball joint

Rear axle powers the Porsche's gearbox via a couple of clutch gears in order to allow different motor speeds when steering or skid steering - Yes, this 4 kilogram heavy model can even skid steer thanks to its independent motor control.

Here is the end result

As with the original set, I kept the rear axle 2 studs wider than the front:

For suspension I used 4 hard springs, which are hald compressed thanks to the model's immense weight.

Due to the porsche's wide chassis springs are quite far apart, so the flex angle is not really big, but on the other hand that makes the model much more stable.

Performance wise the crawler works very good, despite its massive weight, so far I had no broke U joints or gears and it has enough torque to skid its wheels on hard surface.

Expect more pictures soon and a video soon.

[Marxpek]

30 minutes ago, Zero (Zblj) said:

so far I had no broke U joints

yeah yeah, i'm working on it ;D

I like it a lot!

[technic_addict]

Awesome job!  Do you by chance have PP tires?  The CLAAS tires seem a bit small lol

[Zerobricks]

20 minutes ago, technic_addict said:

Awesome job!  Do you by chance have PP tires?  The CLAAS tires seem a bit small lol

I have PP tyres, they are smaller and dont look as good.

[technic_addict]

1 hour ago, Zero (Zblj) said:

I have PP tyres, they are smaller and dont look as good.

Indeed the PP are slightly smaller in Diameter, but I actually meant they looked skinny, which the PP are much wider.

[Aventador2004]

great work @Zero (Zblj)!! does the gearbox have the same ratio as the front?

[Zerobricks]

8 hours ago, Aventador2004 said:

great work @Zero (Zblj)!! does the gearbox have the same ratio as the front?

Thank you. What do you mean with gear ratio?

[Aventador2004]

6 hours ago, Zero (Zblj) said:

Thank you. What do you mean with gear ratio?

Does the front get as much power? I mean.

[Zerobricks]

3 hours ago, Aventador2004 said:

Does the front get as much power? I mean.

The Porsche's original gearbox is powered by rear axle. But both axles have 2XL motors, one per wheel.

[letsbuild]

WOW! Looks really powerful! I can't wait to see it in action!

[Aventador2004]

3 hours ago, Zero (Zblj) said:

The Porsche's original gearbox is powered by rear axle. But both axles have 2XL motors, one per wheel.

ok, got it. i meant did you connect the gearbox to the front?

[Zerobricks]

1 minute ago, Aventador2004 said:

ok, got it. i meant did you connect the gearbox to the front?

No, the front ball joint carries steering to the steering wheel.

[Aventador2004]

Just now, Zero (Zblj) said:

No, the front ball joint carries steering to the steering wheel.

ok.

[Zerobricks]

Here is the promised video:

 

More pictures of the details and underside coming soon

[JJ2]

Impressive performance for its size, I will be entering the contest soon, I just dont have very many Technic sets to Crawlify thought

Do you think you could lower the body a bit? It just looks maybe 2-5 studs to high

[DTom]

I love it and would love to build it.

I'm looking forward the additional pictures

Edited May 14, 2017 by DTom
Typo

[Leonardo da Bricki]

Finally! A Porsche worthy of buying!

Great job, the performance is impressive for the size and weight of this model.  Though I must agree with JJ2, slightly lowered bodywork might look better.

[Marxpek]

It performs better then i had expected with all that weight!

I did a bit of math and it seems our vehicles have the exact same power to weight ratio (4000gr-800nm/s vs 1200gr - 240nm/s) which makes me think your Porsche can do even more than shown in your video! (mine is up as well in a separate topic would love some feedback!)

But i can understand you do not want to risk a real drop onto rock with the costly Porsche set, and i must admit.. control with IR receivers and making good shots outside is hard with all the sunlight...

Anyway, nice work and looking forward to see more pictures!

[Zerobricks]

As promised, here is the picture of the underside with with all the mechanics

You can see the origiinal brake pieces I used in the wheels:

Size comparison of a minifig to the finished model:

And the remote used to control the model:

Anyone else sees something weird here?

 

Regarding comments about height.

There is no space left between top of the axles and lower body of the Porsche. Front end has only a stud left and the rear around two, and the axles also need room to flex.

Bringing body lower to the axles would require a total rebuild of the whole Porsche chassis, with the gearbox and fake engine ending up in the way.

Besides the body looks so high due to the original high fenders which I widen by two studs to give them enough room for wheels not to get stuck.

[DTom]

? will you make instructions ?

 

[Zerobricks]

19 hours ago, DTom said:

? will you make instructions ?

 

I can make an LDD file with all the changed elements marked

[DTom]

That would be awesome!

[Elmo]

Something new for instructions? It would be great!!!