A question about handling

[Walker]

The question is how would you improve handling of a '78 131 series1 two door. The car is copletely stock and any thing added would have to fit under the standard body work.
Any suggestions would be helpful.

[kev131]

Less technical suggestions would be to reduce weight wherever possible...plus look at wider and lower profile tyres.

Newer (rather) than upgraded suspension parts such as shocks will also improve the handling of '78 car if the old parts are well worn. 

[Fiat 131 Abarth#2]

build an abarth replica with 2,0 l engine 

[Walezy]

First of all set the negative camber to -1 degree. then best will be to fit bilstein b6 shocks and a bit stiffer springs. This will for sure make the car turn nice but with negative camber you may notice a bit of wandering to the left or right side when driving straight but this is nothing too big, just a little bit and it is fully controllable. Good set of 195/50/15 tires will help a lot also.

[Walker]

Should I replace all of the suspension parts, control arms, steering unit,bushings, ect. Or will those items be ok to keep. The car has over a 100,000 miles on it.
And what kind of bushings should I use rubber or plastic?

I looked into building an Abarth, but the cost would be too much. Also I plan on using the car as canyon racer so I want it to look as stock as possible.

[Walezy]

If possible then replace the bushings with poyurethane. Front wishbone has a big rubber bush and it will flex a lot in hard cornering so you need more negative camber to make it handle properly but this will make the straight driving worse so if you have harder bushings then there is no need for more than 1 deg negative camber.
Get some stiffer springs.