tortion barAdjustment!!

[Guilietta81red]

I have just fittes some 6 spoke tsw wheels to my 81 guilietta and was wondering if anyone knew the correct procedure for adjusting the front tortion bars to lower the car. Thanks:

[Tifosi]

'Normally' these cars are lowered by using shorter springs, and in extreme instances, drop spindles.

[beatle_bayly]

TIFOSI: I think he means a 116 Giulietta with Tbar front springing.

GIULIETTA81RED:

Do you have an Alfetta workshop manual ? If not, buy one. Haynes are good.


VERY SIMPLY PUT:
The torsion bars are made with one spline more on one end than the other. I can't recall exactly, and my books are all packed pending an interstate move, but lets say 34 splines one end, and 35 the other.

So, if you just rotate the bar by one spline, on one end only, then you are rotating the bar 1/35 (or 1/34) of 360 degrees. Out at the end of the lower wishbone, this rotation translates into a substantial vertical adjustment of the wheel. Lets say about 1.5 inches. If 1.5 inches is what you are after, then go ahead and rotate the bar on one end only, and one spline only.

To allow for a finer adjustment, Alfa designed the system so that you can rotate the bar at both ends. This then gives an adjustment as fine as 1/35, of 1/34, of 360 degrees (or maybe its 1/34 of 1/35 of a rotation ). This is known as a 'vernier' adjustment and is a stroke of bloody genius.

You need to get a starting figure on the 'height' of the car. You do this by measuring from the inner wishbone pivot to the ground, then from the bottom of the balljoint to the ground, and subtracting one from the other. Next you need to calculate how much you want to lower the car. If I recall, rotating the Tbar one spline both ends, changes the 'height' figure by 1.5mm. Note that this figure is not the actual height off the ground. Just a number you use to calculate and measure your adjustments. Take the readings with the dampers disconnected.

Now a few words of warning. BUY A MANUAL FIRST. READ IT. Then READ IT AGAIN until you fully understand the theory and maths of the procedure. Don't attempt to second guess the theory/mathematics, and don't read things into the procedure that aren't there. Trust me on this

Remember, you are working on an old car, so things may not come apart as easily as the book indicates. You can try to pull the Tbar rearward out of both spines after removing the wheel and disconnecting the damper. It's highly unlikely this will be successful so you will likely need to disconnect the balljoint and maybe even pull the bolts holding the lower wishbone to the body. If you then have success, it's likely you will require a new balljoint and maybe lower wishbone bushings/bearings. You WILL need a wheel alignment/camber adjustment. Some cars have the Tbars well and truly rusted in place.

Lastly, and most importantly, MARK the RELATIONSHIP of EVERYTHING first. This way you can return the splines to the start-point if you get lost in the numbers (which is easy to do !!). I use a sharp puch to mark a dot on both ends of the Tbar, on the wishbone, and on the rear tbar 'bridge'.

All this is off the top of my head, but if it tells you anything, it would be

BUY A MANUAL !!!! Books have pictures.

[Tifosi]

Quote:

Originally Posted by beatle_bayly TIFOSI: I think he means a 116 Giulietta with Tbar front springing.

[Guilietta81red]

Wow sounds like a wee bit of a mission. My t bars have a cover that looks like a adjustment on the rear of the t bar. so your saying that you have to pull the bar out. Do you know who sells the manuels thanks

[beatle_bayly]

Ebay is a good starting point for a manual. Just note that Haynes make two for the Alfetta, one for the US cars and the other for the real cars

I suppose Amazon etc would also have them.

Your Giulietta will have the 'earlier' or longer Tbars that are suppported at the rear end by a removeable cast-iron bridge across the floorpan. Later 116s and the 75 (Milano) have shorter Tbars and they are located by splines welded into the floorpan.

Remove the rearmost eliptical covers/retainers and you will see the end of the Tbar. It's internally threaded so you can use an 'extractor' or puller to remove the bar rearward. I've seen extractor snap before the bar budged

It's been years since I did the job but I'm pretty sure the bar will come clear of the rear splines well before it falls out of the splines in the lower wishbone. This is handy as you don't need to juggle both ends of the bar simultaneously while trying to re-engage the splines.

MARK THE SPLINE RELATIONSHIP BEFORE YOU REMOVE ANYTHING. Oooops, did I say that already ???????????

[Guilietta81red]

yea that is what my car is like. So you have to pull the cast piece off the splines and do you drop the car on a jack. How does the internal thead work. It is all still a bit confusing to me

[Grant]

You might want to read up on Torsion bars in general on the internet first before tackling this job. It takes a while to do, and that's if you know what you're doing. I didn't, and it took me 2 days of straight work. I also ran into problems I couldn't figure out, and had to get help from people with more experience.

This was trying to install 27.3mm torsion bars, but still, it's tough.

[Greg Gordon]

I have a decent write up with pictures on this subject here: http://www.hiperformancestore.com/AlfaSuspension.htm

[La Voce]

http://www.alfabb.com/bb/forums/show...+I+torsion+bar
I just went through this so it's fresh in my mind, PM me if you get stuck and I'll give you my phone number. You are likely facing quite a challenge if the bars have never been removed. My experience was maddening- but I did get it done.