[WIP] Renault 5 turbo rally (WIP V2.0)

[Jurss]

4 years ago I started to build this car model

It finished in this stage for this scale

It finished in some different scale

Main issue was rear tire-wheel combination for that larger scale. I tried to put some larger tire on another tire, but I was not really satisfied with this idea.

But now Lego has made new tires, right for this scale car

So, I'm planning to restart that build. Yes, those rear tires are slightly larger than front, but that is just what it is also on real car.

This will be long build, as I'm pretty busy with work and child teaching.

 

[Jurss]

Sizing in sclaer.sariel.pl

[1gor]

You made perfect wheel/tire choice. Take your time; important is to finish it one day

[Zerobricks]

As Igor said great wheel choice and best of luck

[Jurss]

43 minutes ago, I_Igor said:

important is to finish it one day

I have already worked on some models, which needed some 2 years, so not first time :) Of course, I will try to finish it.

17 minutes ago, Zerobricks said:

great wheel choice

Now there is really good match. I tried some low tire in rear, it looked awfull.

OK, there is some progress.

Needed 23L wide axle for rear. Standard way it is 24, with turntables as hubs, it is those 23 studs wide. In this case I can only attach wheels one way. Otherway some 1/4 of pins are not inside pinholes of rim. But that otherside would look better for this model.

I've had built this some time ago, it is also somewhere in axle collection thread. That was built with CV joints only, and that limits noticeably suspension travel (it touches turntable axlehole part), as it is on right side.

If u-joint is used on wheel side, then there is much more travel possible. This model doesn't require so much suspension travel, bat I used it anyway.

Then there is rear axle with sway bar

Also front axle has sway bar and "interesting" geometry, but it is really OK.

And then both axles connected together

Next I plan to install engine. Also would like to have some 4 speed gearbox. On original car gearbox is behind axle, engine is before. As rear overhang is really short, I won't fit there gearbox. But who knows. I have some ideas, but then it could be not logitudal. Most probably gearbox will be also in front of axle, under engine.

[Zerobricks]

Why are you using turntables instead of normal hubs at the rear axle?

[1gor]

1 hour ago, Zerobricks said:

Why are you using turntables instead of normal hubs at the rear axle?

Really unusual and I think for manual model ordinary different is enough...

[Jurss]

I wrote in the beginning. With standard hubs width would be 24, this way is 23.

[Jurss]

Some small movement.

Tried to add gearbox.

On original it is on back of engine, and this also fits really nicely there, but it is just too long for scale, as rear by measures are only 3 studs longer than wheels back. Also it would be really hard to get some gear changing mechanism to there.

So I needed to put it here, also rise engine

[1gor]

The best compromise is like you made in last image 

[Jurss]

Maybe.

Maybe I will reconfigure it, so that I can bring brack that engine lower. Or I need to check really, maybe that height is in scale.

[1gor]

If you take a picture from side perhaps it could be in scale, from this point I can not see. 

(I know that I can only make small one with 43.2 tires )

...and no transmission...

[Jurss]

I'm afraid, that I need it one stud lower. 2.3 is not top of cylinder top, it is something else, I think.

[1gor]

Perhaps you can put suspension one stud lower; hmmmm, that (if I remember correctly) it could be wider that 23 studs....

To me it looks like suspension arms are parallel to the ground

[Jurss]

Suspension is almost paralel to the ground. If I will put everything on the car, it could be paralel.

Looking at pictures, maybe that is already top of engine. Yes, inlet is littlebit higher, but the difference is not so big with valve cover. I think I will leave it as it is now.

[1gor]

when I was thinking of building one in approximate scale 1:10 (I think you are not far away) engine ended up always about half a stud to high and then I realise that actually shocks were that always raise or lower suspension for about half a stud. Indeed motor-head's upper line is approximately inline with bottom line of rear windows...

My model had rear double 62.4 wheels and not some representative transmission (basically one from 8880 set)...but it was even before 3 studs wide differential...

I agree; the best way is to live it as it is...

[Thirdwigg]

Can you drop the transmission two studs down, and run an axle underneath the differential and connect to the differential on the rear?

[Jurss]

Why? There is already connection. I just haven't added gear there. You can see axle going in that frame, where is differential.

Now I'm just thinking how to connect gear lever to gear box. There won't be simple solution. 24t gear is in the way of simple solution. Maybe I will still need to change gearbox.

[Thirdwigg]

Looking at it again, I guess you don't need to connect the axle at the rear of the differential. You seem to have enough space.

Can the crankshaft come down two studs, or will it get in the way of the differential? 

[Jurss]

No, I don't need to connect at the back, just added missing gear (black one)

That's all.

And I can't move engine lower, even by one, then it will touch gearbox. Yes, if there is no gearbox, then it come 1 down. But then connection gearbox to gear shifter will be even much harder. In fact, it is now almost in scale.

I'm now trying to figure out that connection. At least some first draft.

Edited November 30, 2020 by Jurss

[Jurss]

Made some first prototype of gear switch. Of course, it needs to be rebuilt, as now I can swticth just two gears. Of course, also some limiters are needed etc. And then routing of HOG steering ...

 

[Brickend]

Great thread and a very interesting technical challenge. I hadn't realised that the engine was mounted longitudinally; I'd always assumed it was transverse as per the Cilo V6, so learnt something new today.

Without wishing to be controversial, is increasing the scale out of the question, perhaps using tumbler tires on the rear? I'd always prefer to see the smallest possible solution, but it feels as though you've tested it and Lego gearbox and engine parts are just too large to achieve a technically accurate end result in 23 stud width. I'd really love to see a solution with the gearbox out the back, it's really a key feature of the car.

[Jurss]

If tumbler tires, then what in the front? 81.6x36? They will be somehow too wide and still too flat. And also, in this scale it will be already huge. I don't like huge models :)

6 hours ago, Brickend said:

I'd really love to see a solution with the gearbox out the back

I will think about this one more time.

[Brickend]

You're absolutely right - I was thinking out loud without the benefit of the tires in front of me - it would be insanely massive. 

[Nazgarot]

Very nice build so far. I love the gear linkage!

Good to see some real mocs showing up here. Ther has been way to few the last half year...

_ED_