[MOC] Porsche 918 Spyder

[Isamudyson]

Decided to start clean instead of using the old topic i created for a custom build. I unceremoniously abandoned that build due to moving, birth of my daughter and just general dissatisfaction. I've started the development of this build 6 months ago after i finished building my 42056 and then seeing all the mods done for it on this forum. With that as inspiration, I thought about using 42056 as a base and try convert it into something more modular.  I decided on trying to go with the Porsche 918 Spyder since it is somewhat similar to 42056 and seems more modular from reference photos found online.

I'm still learning so i referenced/borrowed techniques and actual build sections from official models as well as MOC's like Didumos's Hammerhead etc.etc. The build is being done virtually in LDD and tested with parts i have on had. From the pictures you can see i basically borrowed the rear section and part of the engine from from the Hammerhead. It does look a bit long in the rear due to me moving the gear engagement for drive/reverse to t be behind the axle. Will be looking to find ways to shorten it while keeping that function. The front axle, steering column and part of the front passenger body is from the Ultimate 42056 build. Everything borrowed has some modification with possibly the only original portion i made being the passenger frame. DugaldIC's Aston Martin MOC has also given me ideas on how to make the rear wing lift out of the body and will try to integrate that as well. 

I've left this as only rear wheel drive since the actual car does not have a axle going from the rear to the front.

Hopefully i can find time to take pictures of the actual physical build as well as continuing the development very slowly.  Once i can get the base to be more robust and study, i can start on the body panels. 

 

[BrickbyBrickTechnic]

Woah! Awesome progress!

[1gor]

Nice 

 

[DugaldIC]

I really like the modular design, it's looking awesome so far! My only thought Is that single spring suspension at the front might be a little soft but other than that excellent work, I look forward to seeing your progress 

Edited July 15, 2017 by DugaldIC

[Leonardo da Bricki]

Great start, this looks quite promising. Can't wait to see your progress!

[starx]

Impressive! I am actually working on one of these right now as well, though slightly smaller. Cool to see someone else's ideas on it!

[Isamudyson]

On 7/14/2017 at 7:13 PM, DugaldIC said:

I really like the modular design, it's looking awesome so far! My only thought Is that single spring suspension at the front might be a little soft but other than that excellent work, I look forward to seeing your progress 

I will probably changed it to dual springs but going to get structural integrity set first.

I was able to spend some time and test everything i've done so far in LDD. There was a ton of flex on the rear of the passenger compartment even with the rear engine pod connected. The front end connection area will also dip down with just the body weight. After some some test and quick modification I went back into LDD to make additional changes.

This was how the frame was in the last revision

 

This is the current revision that i will be using to rebuild the compartment. The front and the rear have been strengthen in hopes there will be much less flex. With the way i have changed the front end connection, the front axle is probably going to be made into 5 different parts that will be attached. 

 

I'm beginning to feel that making the car modular this way makes it more complicated. 

[starx]

2 hours ago, Isamudyson said:

I'm beginning to feel that making the car modular this way makes it more complicated. 

It definitely does, but in the end it is extremely rewarding. Very hard to do it well like sheepo or crowkillers.

[Isamudyson]

The current iteration built with the parts on hand. Structurally it is pretty sound. There are probably some additional tweeks that i would need to perform to clean up the design and lighten it. Current sits barely 1 stud off the ground.. i can only image how low it will be with panels on. Definitely will need to redo the suspension.

 

 

[Isamudyson]

Got my additional parts in. Did additional modifications on the rear pod portion. I have rebuilt it so the transmisison, engine and rear axles can be separated easier. The rear axle has also been changed. Hopefully it will be stiffer.  The left is the new build. The right was the test mule i've been working on from the LDD files. 

[Isamudyson]

Alot of tinkering the past few days. This is slowing turning into a car that will have multiple modules. 

In the last version of the rear pod, the rear axle was from Didmous's rugged super car but with out the 42056 shocks. I noticed it couldn't support the weight. So thought about making a variant of the 42056 axles instead. In the process. i ended up making the rear pod module as well. This would allow me to try out different rear axle configurations easily as long as i follow the 6 mount points

This is the only good picture i have so far.

[move5]

Is that a 4 speed gearbox?

[Isamudyson]

Its a 4 Speed gear box

Current finding solutions for the front axles. The single Shock setup was too soft. Also with the redesign of how the front axles connected, I needed to make the axles attach not as one whole piece but in seperate parts.

after a couple of tests this is what i came up with

it seems to be stiffer but i haven't made sure the connection points to the frame will be strong enough or if the steering rack will be fine. 

[Jeroen Ottens]

I woud advice to add some bracing between the upper and lower wishbone otherwise the balljoints will pop out when you compress the suspension.

[Isamudyson]

On 7/28/2017 at 3:56 PM, Jeroen Ottens said:

I woud advice to add some bracing between the upper and lower wishbone otherwise the balljoints will pop out when you compress the suspension.

Thanks for the advice. I didn't even realize there is no support there.

Went ahead and did some changes to brace the upper arm and the bottom arm. In the process i had to move the shock positions. 

I'm going to try this out and see if there is enough structural strength when i attach it to the body 

[Isamudyson]

After playing around on some late nights this past weekend i applied what i did to LDD and vice versa.

I think i have figured out the best option with the front axle. The structure itself is pretty sturdy and should fit right into the frame.

 

My current progress so far with all the various modules connected together. The one area i won't be able to keep from being its own part will be the windshield.

 

Once i shore up the connection point to  the rear end i can start working on shaping the exterior and figuring out how to connect it all to the frame. 

[Isamudyson]

A quick update on the frame build. First image is of the various parts. The rest is it all combined

[AFOLegofan66]

really nice job so far....

[romashkaman]

A very interesting build! But the steering rack is placed in front of  the suspension, so it causes a kind of inverted Ackermann steering geometry - it leads to the model not going into corners well. I had that issue in my model and it led to me rebuilding the whole front suspension, as well as the engine bay. Better rework it earlier, than later)

[tomek9210]

8 hours ago, romashkaman said:

A very interesting build! But the steering rack is placed in front of  the suspension, so it causes a kind of inverted Ackermann steering geometry - it leads to the model not going into corners well. I had that issue in my model and it led to me rebuilding the whole front suspension, as well as the engine bay. Better rework it earlier, than later)

Yes, if placing the rack in front ofthe axle, its pivot point should be more to the outside. Do Porsche rims allow for placing 1x2 axle-pin hole connector so that the pin hole is oriented toward the outside of the car?

[Isamudyson]

I'm not to worried about cornering. The steering rack on the 918 is towards the front of the suspension as well. Also making it module so things are put together similar to how the actual car is built. I have tried the rack behind but it made making the structure firm and easy to take apart troublesome. 

[Isamudyson]

Made revisions to the windshield connection and parts of the rear. i believe i have the frame all set so starting on the exterior. 

Please excuse the colors as i'm working in LDD to test a few items. there are alot of gaps but i believe i should be able to have them filled when i start building

If there's any advice/tips for paneling would be great.

[Alex Ilea]

Why are you missing the front hubs in LDD?

[Isamudyson]

Was able to get in some build time to see how the panels fit. 

With what i have on right now the weight is of the whole thing seems to already equal to the 43056 set. I apologize for the quality of the pictures as i don't have much space right now.

 

 

Any tips would be greatly appreciated

Edited August 16, 2017 by Isamudyson

[Aventador2004]

Looks like it is coming along well, I see the back panels look good.

Why are the liftarms behind air intake black?