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Maybe a problem?

G

Greeney in France

Bloody nice bloke actualy
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This is going to take some explaining?
Firstly when dismantling the car there was no reason to believe it had been in an accident, no tell tale signs hinges still painted in place etc no chassis or panel repairs apart from scraps and dents. Donc (as the french say)
While working on the restoration R4 I have just done the brakes bearings and shocks and I noticed something I hadnt before. It has no wings on either.
On the RHside (looking from the back) I can see about 40mm of the top of the chassis rail after where the suspension arm bolts on but on the other side I cant see any, (i have taken a photo which i can put on this evening) this got me measuring frantically does this mean the body is wonky (technical term) on the chassis? Well the edge of the chassis rail to the edge of the sill covering is the same both sides. From the centre of the wheel to the edge of where the sill starts the is about 30mm difference from one side to the other, there is about 20mm difference beween the inner wing to the inner wall of the tyre from one side to another. I have no one here to help measure at the moment but should the measurement from wheel centre to wheel centre front to back be the same?
Am I worrying needlessly or do I have a serious problem.
I can see NO reason what so ever as to why the above I have no chassis kinks or major body damage but the measurements dont add up.
Thank you
 
This isn't just that the one rear wheel is a little further forward than the other is it? (That's normal - rear wings are different shapes to compensate.) Or are you saying one wheel is closer to the middle of the car than the other? Shall look forward to photos.
 
I do feel a bit of a numpty! I did have a feeling it was something geometric, or to do with the torsion bars as there was a definate chassis length difference. Did nt even think of looking at the rear wing profile though until a friend popped in and caught me measuring frantically:roll: Have you looked at the wings he said? different arch profiles:rolleyes:bloody french!!
Thank you for the quick response though. lesson learned.
 
Missed opportunity there - we could have had you measuring all sorts of bits on the car :D
 
It's so they could have the trailing arms the same length, while using full width torsion bars for soft suspension. The alternative way around (the thing that everyone else does) is to have one torsion bar above the other rather than in front. That's only to make the bodywork look the same from both sides rather than for any technical reasons (arguably that's worse for handling as the torsion bars would be pivoted at different heights).

Renault's solution is beautifully pragamatic. It's not possible to look at both sides of the car at the same time so nobody will notice. Doesn't make any noticeable difference to handling having one rear wheel a little in front of the other, and the rear wings on each side have to be different panels anyway, so why not make them a little more different.

It's a cool Renault 4 thing. There's a lot of seriously cool engineering design in these cars. It's a basic car that's 30 years out of date these days, but production started 45 years ago which makes it groundbreaking.
 
The most amusing part of the famous R4 unequal wheelbase is that the sill chrome strips are consequently of unequal length. While you can't place a right rear wing on place of a left, you can surely mix the chrome strips and then wonder why the strip is longer!
The unequal wheelbase almost drove insane a lot of bodyworkers who had no experience here back in the '70s and '80s. They used to take diagonal measurements on the chassis after a crash repair (instead of mounting the car on a chassis jig). Imagine their surprise when they were measuring such a difference from one side to the other (and after some hard work on the car...). Just like Greeney's!
Note that other Renault cars based on the R4 engineering (R5 Mk1, R6, R16) have also unequal wheelbase.
 
I have to admit I did just that. I must have wasted 2 hrs MEASURING!! from nut to nut, nut to chassis leg on the front.What made it worse is I have a slightly out of square tailgate aperture about 10mm from diags. So I was frantically measuring and looking for problems. THEN after I posted I got underneath and started looking at it logically and notice the torsion bars. My friend popped in and suggested I look at the wings and then I saw the difference.
I thought at first it might be a geometry thing and wondered whether a RHD vehicle would have the same but on the other side? I WAS BUZZING BY THIS TIME!!
I can now tell everyone here like I knew it all the time?? What a hoot
 
does seem a strange idea in todays engineering but most of us old school renault generation have never given it a second thought
think this youtube video illustrates it well (could be our serbian r4 friends messing about)
http://www.youtube.com/watch?v=FeKsbHhJFzY
 
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