as the car is mostly for track i want to stiffen her up a bit.

have an upper from strut brace and i am in the process of making a lower front brace and an upper B pillar brace.

dont want to spend loads so a roll cage is not an option at the moment. looking for some other worth while bracing points that i can fabricate myself.

any inspiration???

Chances are a car of this age will have lost some of its structural rigidity over time, due to the stresses envolved in ordinary driving.

The cheapest way to gain some of that back is to seam weld the main stress points, front suspension, floor pans, rear chassis rails and sills being the most accesable areas. After that, roof to pillar joints rear panel, front panel etc.

It all depends however on your suspension. The more you stiffen a chassis, the more stress you shift onto suspension components. It all has to work in harmony. It's a fine balance, that's why companies spend so much on cad and r&d to maximise handling at minimum cost.

Thankfully for you, I don't think overall handling was the main concern when fiat made the cinq, their budget just wouldn't have allowed it. So there is room for improvement.
I don't like bolt on bracing myself, anything that bolts on will still have a small amount of play, due to tolerances nessesary to be able to fit the component. You could copy the braces and weld them in, hydraulic presses are handy to lever the sections apart to provide pre-tension.
But however much you brace, you must spend as much time and effort on the suspension. Loose as much unsprung weight as possible to allow the suspension to respond quicker to road imperfections, because by stiffening you have taken away some of the secondary flex nessesary to keep all tyres in contact with the Tarmac. Loose a couple of psi out the tyres to help with this also.

Imagine the car in a turn, the front will load up on side and compress the suspension, the chassis will flex slightly also. Pushing the strut up and in toward the centre. If this flex wasn't there, the body would remain solid and the suspension would in turn have to compress slightly more. As the strut moves up and in slightly, it maintains more of its original geometry keeping the wheel more upright rather than allowing it to tip over onto positive camber.

thanks for your reply.

im not going to go the seam welded route as my welding leaves much to be desired and after seeing the hassle my mate went though getting his uno done, i dont have the time for that right now.

the upper front strut bar has an adjuster to put some tension across the strut tops. my lower support bar is made of box section for increased strength. my Bpillar brace is bolt on, but i will also be adding an adjuster to add tension.

i plan to do some weight saving too. just wanted to do a little work before my next track day to see if i can make some improvements without going too mad or spending too much at the moment. i appreciate im not going to see a wow effect without going for a full cage or suchlike, but a little improvement at the moment would be nice.

thanks

Preloading the bracing is a lot better than just static bracing.

I think the thing you will notice more is as the car gets stiffer it will respond worse to bumps mid corner. That's where any weight saving on suspension components will help. It is a shame you can't get aluminium calipers and brackets. They seem to weigh a ton.

When is you're next track day?

havnt booked one yet, but will be within the next few months i would hope. once the car is all done i will book one as my friend has just about finished his car too

dont want to go mad with it at the moment. just want a bit of fun and wouldnt mind making the car a little better for track work.

How about C-pillar section area, about midway up. I've seen Punto's with that setup, back seats removed & a torsion brace in instead.

robotfireengine said:

How about C-pillar section area, about midway up. I've seen Punto's with that setup, back seats removed & a torsion brace in instead.

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after the front upper brace, front lower brace and B pillar brace i was thinking of an X brace for the rear between the top seatbelt fixings and the lower rear seat fixings.

will see if i have time to bosh one together before i get a track day booked. need to get the tracking redone and some extra neg camber put on the front next week