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Discussion Starter #1
Hi Guys,

I am thinking of upgrading my torsion bars on my 1984 Giulietta 2.0L with something a bit thicker. I plan to use the car for street driving and the occassional track day. I think 28mm are to big and was hoping to find a pair of gtv6 bars or similiar. I have seen an alfetta sedan with 25mm but they seem hard to source at the moment. Can anyone confirm the size and length of the gtv6 bars, as well as what suspension modifications I can do. I already have koni suspension in the car.

thanks;

Marco
 

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Hi Marco,

I made some research on this particular topic in the alfetta&gtv6 forum since I also wanted to upgrade the TB in my 82 alfetta-gtv. What I found is the following:

- gtv6 bars are the same diameter as the first entry level upgrade that Shankle offered for alfettas.
- 25.4mm was an upgrade for alfetta and gtv6, people who have them agree that it is the best set-up for street.
- 27mm, used for track, others use them in the street. They are not so easily installed as I am aware.

You should be aware that 1980-1983 alfetta/gtv6/giulietta TB are the same and are longer; later gtv6 TB(I think 1984) are shorter and are the same as Milano/75. I don´t know if this also applies to alfetta/gtv2.0/giulietta so you must measure yours.

I have a set of 25.4mm TB that I haven´t installed yet as I want to put them in with a set of Koni sport shocks (yellow), so I can´t report any feedback on this, other who have them may chime in.

You may read the folowing threads:

http://www.alfabb.com/bb/forums/milano-75-1987-1989/146801-25-4-torsion-bars.html#post712454

http://www.alfabb.com/bb/forums/503891-post13.html
 

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Discussion Starter #3
From memory Giulietta torsion bars are 990mm long. Yes the alfa 75 and late gtv6 bars are shorter. I will read up on those links you posted.

thanks;

Marco
 

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Discussion Starter #4
I have found a set of early gtv6 torsion bars which are 23.5mm diameter by 990mm long. What do you think of these as an upgrade?
 

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The GTV6 bars have about a 70% increase in wheel rate over the 4 cylinder TB's. That should give a nice increase in control and response.

Other modifications that work nicely are a big increase in caster angle. 3* is standard but 5* should be the minimum. Low speed steering will be heavier though. The standard cater arm chassis mounts should be replaced with at least polyurethane bushes. Many people also upgrade to the 105 caster arm ball joints for even greater consistency.

I use Vin Sharp's/Pace Engineering's long shank top ball joints in my road going 75 V6. I really liked the added camber gain with bump travel as this helps to keep the outside front wheel perpendicular with the road when the car body rolls.

The battery in the boot is another good maneuver. Not only does it give better weight distribution (not as much of an issue with the 4 cylinder cars), but the battery's polar moment of inertia effect on the car is quite large because it's a significant mass that is a long way from the cars centre of gravity and it's forward of the front wheels.

I think with those modifications, the little Giuli would be very lively. I remember my 1980 model, which was basically standard except for gas shocks, and it always felt a bit lethargic at lower speed, tighter turning. It was awesome fun when the corners opened up and the speeds increased, but I would have loved having a more responsive front end to help make the most of the rear end grip.
 

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Discussion Starter #6
The GTV6 bars have about a 39% increase in wheel rate over the 4 cylinder TB's. That should give a nice increase in control and response
That sounds great and should be a decent improvement for standard parts. I have x2 alfa 75 V6 which also have thicker sway bars. Would it be worth installing them aswell with the gtv6 torsion bars.

The standard cater arm chassis mounts should be replaced with at least polyurethane
I have considered this already and will be purchasing the superpro brand which is made in Australia.

The battery in the boot is another good maneuver
This also have been done due to my multi throttle efi system and a more neat engine bay.

As I have almost made my decision with the GTV6 torsion bars, I need to seek a set of decent rear springs. Can anyone make a recommendation of what to consider. As mentioned this car will be street drive, as well as the occassional track day.
 

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I have x2 alfa 75 V6 which also have thicker sway bars. Would it be worth installing them aswell with the gtv6 torsion bars
Some people use the front sway bar from the Milano verde (75 3.0) which is 24mm; I have one but not yet installed so I can´t report on this. My gtv2.0 came with 22mm rear bar which is the same as the gtv6.


As I have almost made my decision with the GTV6 torsion bars, I need to seek a set of decent rear springs. Can anyone make a recommendation of what to consider. As mentioned this car will be street drive, as well as the occassional track day.
Maybe you could start with gtv6 rear springs since they match the TB, then you may want to continue the upgrades. The rates of TB and springs is in the second link I listed.
 

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Discussion Starter #8
Some people use the front sway bar from the Milano verde (75 3.0) which is 24mm
I am try this then, as I should have this sway bar.

Maybe you could start with gtv6 rear springs since they match the TB
I can source these as well, however I dont want the car setting extremely high at the back. If I recompress my spring to suit my ride height will this impact on performance or should I get a new set made to suit the torsion bars and ride height by a spring manufacturer?
 

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If I recompress my spring to suit my ride height will this impact on performance or should I get a new set made to suit the torsion bars and ride height by a spring manufacturer?
You can get the springs reset by a spring winding company. The important thing is to make sure that there is the same number of 'active' coils (coils that are still free to compress), otherwise the spring rate will increase.
I'd suggest putting the GTV6 springs in the car and sitting it back on the ground (bounce it a few times to make sure its completely settled). Then look underneath the car and count the number of free coils. This number has to be maintained to retain the original spring rate.
Also, measure the rear height of the car, because with out some sort of base height with the new springs, you won't have any idea of how much the springs will have to be reset.
 

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Discussion Starter #10
You can get the springs reset by a spring winding company. The important thing is to make sure that there is the same number of 'active' coils (coils that are still free to compress), otherwise the spring rate will increase
I will have to look into this and make sure it doesn't occur.
 
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