Porsche 'Inner' Workings

[DrJB]

While many MOCs have focused about looks/aesthetics (the many Italian cars), and others about number of functions (LandRover), I have not seen many that replicated 'correctly' some supercar features. I'm thinking of the following:

1. Multi-link suspension (negative scrub radius) for better handling

2. Low boxer-type self-balanced engine as in Porsche and Subaru

3. Porsche suspension, where springs do not necessarily travel along the vertical. I have pics from an auto show, gotta dig them out.

Any pointers or features I've missed out?

[Meatman]

It seems to me that to properly execute what you are thinking that the model needs to be larger in scale that Lego makes wheels for. This may explain why you do not see them as much. The smaller the scale obviously the less important that it is to some builders(including the Lego design team) to worry about being as realistic to a model as possible. Because in the end, no one is going to get anything perfect.

[zux]

Well i think few of your mentioned items already have been implemented in one or another way:

1. nicjasno (if I get nickname correctly) has done lots of different suspenion models

3. 8458 and 42000 have springs traveling horizontaly.

Looking forward your ideas as both sounds interesting for me.

[aol000xw]

Yep those

touch on all those features. Scale is a big problem, shallow rims another one.

One you try to design it properly your axle track goes up and up, and your wheels look ridicously small.

[cgg199]

Try adding disk brakes to the front wheels once you have got all the suspension geometry correct with camber, caster etc. It's tougher than you think when you start designing.

[nicjasno]

Disc brakes are completly out of the question. There's no room for that at all and no proper parts. All current attempts are useless. Better have drum brakes on the side of the rear differential if you really want to stop the car.

[DrJB]

Try adding disk brakes to the front wheels once you have got all the suspension geometry correct with camber, caster etc. It's tougher than you think when you start designing.

Agreed ... I never implied that it was 'easy'. Yet, the big challenge is to get 'standard' lego parts to mimic real life contraptions. I once built a cardan joint out of technic bricks, plates, axles and pins (only). It was huge, but this was 30 years ago, and the small lego cardan was not available back then.

Edited October 9, 2013 by DrJB

[Lipko]

I like it when we talk about these realistic suspension angles. What are the realistic values for those angles? Probably a few degrees. Not something you would notice in Lego, since the slack of a Lego suspension is more than that anyway.

gee, why not adding windshield-wiper or a radio or working ignition system or a starter unit or air conditioner or adjustable steering wheel or working valves with proper timing and pre-ignition regulation, or something else pretty much default in cars? Why it's always the suspension details and the almost useless brake-systems that everybody wants? Or working pedals that pretty much do nothing but moving some linkages that doesn't have anything at their other ends.

The reason why not so many realistic stuff is packed into a Lego car because it wouldn't be that cool, if it would work at all.

A sci-fi horror thriller western porn comedy wouldn't be that cool either.

Edited October 9, 2013 by Lipko

[DrJB]

I like it when we talk about these realistic suspension angles. What are the realistic values for those angles? Probably a few degrees. Not something you would notice in Lego, since the slack of a Lego suspension is more than that anyway.

gee, why not adding windshield-wiper or a radio or working ignition system or a starter unit or air conditioner or adjustable steering wheel or working valves with proper timing and pre-ignition regulation, or something else pretty much default in cars? Why it's always the suspension details and the almost useless brake-systems that everybody wants? Or working pedals that pretty much do nothing but moving some linkages that doesn't have anything at their other ends.

The reason why not so many realistic stuff is packed into a Lego car because it wouldn't be that cool, if it would work at all.

A sci-fi horror thriller western porn comedy wouldn't be that cool either.

A multitude of opinions here again. Please read my reply above. The goal here is not to push the realism to an extreme, as I was not asking for wipers or ashtrays ... I am (granted, others have different interests) after reproducing some real life mechanisms with the 'limited' parts assortment in Lego. However, if you feel you want to add wipers, do not forget the washer fluid, and might as well add a radio in there ... ;) Edited October 9, 2013 by DrJB

[cgg199]

Agreed ... I never insunuated that it was 'easy'. Yet, the big challenge is to get 'standard' lego parts to mimic real life contraptions. I once built a cardan joint out of technic bricks, plates, axles and pins (only). It was huge, but this was 30 years ago, and the small lego cardan was not available back then.

I have only been alive for half of that length of time, so I found it hard to relate to times with unspecialised parts, however I do understand what you mean by this. Without specialised parts, creations do get over sized and can sometimes be overcomplicated. It adds to the fun!

[Lakop]

A good start would be for lego to build us a large porsche set and we could take it from there.

H

[legomuppet9]

Sheepo's 911...

[Meatman]

Sheepo's 911...

It is an astonishing model, but not quite build in a Lego style fashion.

[clarkdef]

Any detailed suspension I have made was large and weak, which is ok seeing how it was just a model, but I don't feel satisfied unless it's strong and I know it is... So I end up using Lego arms and hubs :/

so instead of focusing on mimicking real world suspension, I focus on application and execution in the world where my Lego car must drive, and this approach is satisfing.

The breakthrough was learning that preloading the plastic by stretching it out and pegging it down was great! Suspension works so much better when chassis are preloaded.

So do what makes you happy I guess.

[Phoxtane]

The breakthrough was learning that preloading the plastic by stretching it out and pegging it down was great! Suspension works so much better when chassis are preloaded.

So you put tension on the chassis to make it stiffer then?

[clarkdef]

So you put tension on the chassis to make it stiffer then?

Yes, anywhere I can.

[DrJB]

Yes, anywhere I can.

I am not sure it is preload in the classical sense I.e., taking advantage of nonlinear material/geometric properties. I think it is instead preload to compensate for gaps/clearances and there are many of those in any sophisticated model. Possibly a combination of both though.

[clarkdef]

I am not sure it is preload in the classical sense I.e., taking advantage of nonlinear material/geometric properties. I think it is instead preload to compensate for gaps/clearances and there are many of those in any sophisticated model. Possibly a combination of both though.

Lol let's not get too particular about it, I'm bending some plastic.

[DrJB]

Lol let's not get too particular about it, I'm bending some plastic.

Sorry, mechanical engineer here ... Lol