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'69 1750 Spider Veloce (Euro)
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Discussion Starter · #1 · (Edited)
My 1969 Spider 1750 has the original springs. They are covered in surface rust, but seem sturdy. Is there any reason to think that they need to be changed? Neither the front, nor the rear seems to be sagging. Could I expect a significant change in handling if I were to replace them, or should I just focus on replacing all the (original) suspension bushings first? I’ve done most in the rear and now have to do those in the front. The car seems to oversteer at speed in some corners.
 

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1969 1750 Spider Dual 45DCOE (converted)
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I removed mine during the undercarriage renewal and decided to media blast them to ready for paint. I cut the rubber section off of them and blasted them and found very severe rust pitting where the rubber was covering them. I am wondering how the pitting would compromise the performance for street driving. I am looking into replacing them but need to find a source.
 

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I would suggest you focus on the basic consumable suspension components first, such as bushings, shocks, before you turn to springs.
You say there does not seem to be any sagging, so at this point unless you want a new set of springs I would move on.
There are factory specifications you can refer to in order to verify the correct ride height of your Spider.
And you mentioned the oversteer at speed, the 1750 spider did feature a rear anti roll bar as a first on the 105 Spider. I have read that this along with changes in spring rates did diminish some of the understeer that was a characteristic of the original 1600 Duetto, which did not have a rear anti-roll bar.
This may have been discussed in some of your previous posts, but the rear suspension bushings must be in good condition to properly locate the rear axle. If the trunnion bar bushings, and/or the trailing arm bushings are worn and weak, you will experience more oversteer than was designed into the car. I'm not sure about the age of your tires either, but that has a major effect on predictability of handling.
 
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'69 1750 Spider Veloce (Euro)
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Discussion Starter · #4 · (Edited)
I would suggest you focus on the basic consumable suspension components first, such as bushings, shocks, before you turn to springs.
You say there does not seem to be any sagging, so at this point unless you want a new set of springs I would move on.
There are factory specifications you can refer to in order to verify the correct ride height of your Spider.
And you mentioned the oversteer at speed, the 1750 spider did feature a rear anti roll bar as a first on the 105 Spider. I have read that this along with changes in spring rates did diminish some of the understeer that was a characteristic of the original 1600 Duetto, which did not have a rear anti-roll bar.
This may have been discussed in some of your previous posts, but the rear suspension bushings must be in good condition to properly locate the rear axle. If the trunnion bar bushings, and/or the trailing arm bushings are worn and weak, you will experience more oversteer than was designed into the car. I'm not sure about the age of your tires either, but that has a major effect on predictability of handling.
Thanks! I will focus on finishing the bushing replacements for now. The shocks are new from 2020, as are the tires. The rear suspension bushings have all been replaced except for the trunnion-to-diff conical ones and the big trunnion-to-chassis arm ones.
 

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OK, then I bet you will feel a difference once those bushings are replaced. I have poly on the T bar at the differential, and original rubber up at the pivot bushings at each end of the T bar.
 
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I concur with Alfaloco on getting the bushings and ball joints and an alignment first and this will give you a good baseline.

At the risk of going off on a tangent I will try to explain why the 1750 got a rear antiroll bar and will end with a suggestion. This comes from a talk with Max at Alfaholics. During the 60's Alfa was racing the GTV/GTA in competition. One of the problems was that the rear top pickup point is a little too high and it was negatively affecting roll centers. It was about impossible to change the pickup point on the differential, but they could change the front uprights to improve geometry. When they did this for street cars it caused the cars to oversteer and thus they added a rear sway/antiroll bar.

As far as your springs in a perfect world they should really last forever, they never go into yield and the oscillation are low enough that they will never hit fatigue life. In reality corrosion and other factors will end their lives at some point, but without testing I don't know if they need replacing or not.

A suggestion - if you replace the spring go with a stage one spring kit. These are available from Alfaholics/classicAlfa/ OMP and more. This will drop the front end and change the roll centers and eliminates the need for the rear bar. That along with some good shocks makes a nice handling street car that will not beat you up.
 

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But Mad North-Northwest
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At the risk of going off on a tangent I will try to explain why the 1750 got a rear antiroll bar and will end with a suggestion. This comes from a talk with Max at Alfaholics. During the 60's Alfa was racing the GTV/GTA in competition. One of the problems was that the rear top pickup point is a little too high and it was negatively affecting roll centers. It was about impossible to change the pickup point on the differential, but they could change the front uprights to improve geometry. When they did this for street cars it caused the cars to oversteer and thus they added a rear sway/antiroll bar.
I'm not sure that makes sense? A rear anti roll bar would increase oversteer, not decrease it.

Anyway, in the absence of other issues like sagging I'd base spring replacement on whether they look solid or not. I would suggest poly for the trunnion conical bushings and washers. Based on my recent experience I'd also suggest poly or heavy duty rubber for the trailing arms.

 

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I'm not sure that makes sense? A rear anti roll bar would increase oversteer, not decrease it.
Not on a 105. It is an easy test, drive a 105 with a bar then disconnect it, you don't even need a test track. Without the rear bar hanging the rear out becomes incredibly easy
 

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I had the same thought about my coil springs, they are original.
My car still has proper ride height and all other suspension wear items were changed.

Since I had already replaced all bushings and shocks a couple years ago, I was thinking about doing what KL Harper said, but with the Alfaholics " fast road kit".
www.alfaholics.com/parts/105-series/steering-and-suspension/alfaholics-has-developed-a-range-of-4-suspension-p/

You would think that after 50 years the original coil springs would have lost some travel flexibility.
 

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'66 Sprint GT, '67 Duetto, '70 BMW 2800CS
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You would think that after 50 years the original coil springs would have lost some travel flexibility.
Well, not really. How often do you replace your valve springs? Modern spring steel is designed to retain its elastic properties after a LOT of cycles.

Deep pitting due to corrosion is another story. If your springs are badly rusted, then sure, they may be prone to sagging or breakage.
 

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Well, not really. How often do you replace your valve springs? Modern spring steel is designed to retain its elastic properties after a LOT of cycles.

Deep pitting due to corrosion is another story. If your springs are badly rusted, then sure, they may be prone to sagging or breakage.
No rust, no sagging.
I hear what you are saying.
That is a very good analogy.
Thanks Jay.
 

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Well, not really. How often do you replace your valve springs?
I will be when I rebuild my 1750s engine. My father did when he went through his MGB engine to prepare it for classic racing.

Springs do age, leaf springs much faster then coils. I was going to replace my suspension springs but they still measure in spec. Probably because they have done nothing for the last 30 years
Pete
 

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My 1969 Spider 1750 has the original springs. They are covered in surface rust, but seem sturdy. Is there any reason to think that they need to be changed? Neither the front, nor the rear seems to be sagging. Could I expect a significant change in handling if I were to replace them, or should I just focus on replacing all the (original) suspension bushings first? I’ve done most in the rear and now have to do those in the front. The car seems to oversteer at speed in some corners.
Do the bushes anyway, I changed the rears because it used to bottom out (fully loaded), all good now, fronts still seem in good condition and nice and compliant, changing springs won't change handling much, new bushes etc will make a significant difference if they are original
 
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