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Discussion Starter #1
The suspension on my 86 Spider is the original. It appears that the engine mounts are starting to sag, so I was considering a suspension upgrade "while I'm at it" this winter.

I have some credit at IAP to use.

What shocks, springs, and bushings wouild you recommend for a street car? My thoughts to date are KYB gas-a-justs, upgraded IAP springs, and the stock rubber bushings (+ motor & tranny mounts).

They are expensive, but what about a chassis stiffener?

Thanks for your thoughts. Dickson
 

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My answer is: it depends... How does your Spider behave now when hitting bumps?. My two previous Spiders didn't do anything out of the ordinary, but my '91 had a severe case of the shakes; It seemed like everything was vibrating in a different direction when hitting a bump. Apparently, the chassis harmonics in the S4 are different than earlier versions and, in my opinion, it vibrated far worse than earlier versions. I added a chassis stiffener, and it helped. There is a long discussion of stiffeners on the BB. Use search to find and read.

For other upgrades, like poly bushings, there is another long BB discussion. I installed poly bushings in the trailing arms of my '91 spider, and this resulted in additional vibration transmitted to the passenger compartment. Some people have removed their poly installations.

...They are expensive, but what about a chassis stiffener?...Dickson
 

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You must decide what you want out of your upgrade. Do you want higher cornering speeds and if so, how much harshness are you prepared to put up with? Some people are fans of gas shocks. I am not. If you just want to corner faster then install wider, lower profile, stickier tires. I am happy with a lowered car with stiffer springs. I also like having adjustable top A arms so that I can set the camber where I want it. I also like poly bushings but others don't. I have not been convinced that a chassis stiffener will make my car handle much better so I didn't spend money to increase the weight of the car.
I have no doubt that someone with exactly the opposite opinion will balance my post.
 

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Discussion Starter #4
Thanks guys. My car is an original 57,000 mile car. It's been well maintained, and is much tighter than my previous, higher mileage cars.

However, I agree that the wonderful handling is a big part of the enjoyment these cars have to offer, so I want to squeeze every drop!

I do not want additional ride harshness, nor do I need an adjustable or race ready suspension.

For what my car is - a car that I aspire to drive as often as daily for the 5 miles to & from work - I think that new rubber bushings, upgraded IAP springs & sway bar, and maybe a chassis stiffener would be the most appropriate combination.

I can't go wrong here. It does shake over bumps, so even a stock to slightly upgraded suspension will be an improvement.

I guess my biggest question may be the chassis stiffener. Due to cost and weight increase, I'll probably hold off for now....Thanks - Dickson
 

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A stiffener will add about 40lbs. (it and the box it comes in weigh 44lbs)
Removing the spare tire would compensate for 30+ of that easily enough, so the car would weigh the same.

Upside is all the weight is added to the very bottom of the chassis, so it lowers the COG by a small amount regardless of the presence of the spare or not.

Things end up almost as inflexible as a hardtop car.
Not quite, but far closer to it than an un~stiffened convertible by a pretty wide, and noticable, margin.

Ideally you'd get a chance to drive a stiffened car before finalizing your decision as there's a lot of differing opinions on them, but until you actually drive one, you'll never know for sure because both the pro and con opinions are still just other peoples words, not your butt in a seat telling you exactly what you want to know but cannot tell from intangible responses from the aether.
 

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The stiffener is a nice upgrade. I can tell you from experience that if you stiffen the springs and shocks, you'll notice the chassis flex more. The stiffener helps with this.

Personally for shocks I like the Koni's. I don't have any experience with how the KYBs ride, but they appear to adversely affect the ride height (several Spiders I've seen with them look "jacked up").
 

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A common approach on the BB is to upgrade the springs - centerline or IAP are common. Then you usually need stiffer sway bar in front (much less often in rear). Some only replace front springs as the car handles well with the rear as soft as possible. Koni yellow set at mid range on the front and Koni red at rear on full soft. One limitation of lowering the car is that you get some "bump-steer" effect. Alfaholics and some others have a kit to counter this too. Be sure your route can take the already low oil pan being an inch lower yet! Or use spring spacers to restore normal ride height with the stiffer springs.

Wider tires will significantly affect the steering effort.

If you enjoy driving the car now, you might be disappointed with any of these changes. Alfa's are already pretty good. You'll make it different, but 'better' is very subjective. Track-like handling is not always fun on street driving, especially for a daily commuter.

Robert
 

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I am starting a restoration on a '69 spider that is used in pretty much the same way. Just as you I am quite happy with the car. The car came to me with a stock spring set and yellow Konis. I put a chassis stiffener on two year back. I have not noticed a huge amount of change. ON the plus side the car demonstrated MUCH less cowl shake and is definitely quieter over bumps. On the minus side I have noticed that on a few areas of road with (properly spaced) bumps the car can get to bouncing a little before it settles. My simple thought was to just lower the car by an inch all around by cutting the stock springs down. My reasoning was that I had heard that these cars overall height was raised to meet US standards, so they are more "correct" when lowered. Also it looks cooler. I am at a point in the project where I could change plans altogether, so I am curious to hear expert recommendations here. I would like to imagine that I could take the car on track day events and beat my Mini Cooper's times, but I'm sure that would be many more dollars and lots more compromise...
 

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On the minus side I have noticed that on a few areas of road with (properly spaced) bumps the car can get to bouncing a little before it settles.
Improper damper/spring match.
Springs are overpowering the dampers, or the valving is not right in the dampers.
That's got nothing to do with the stiffener.
You prolly just feel it more now onnaconna the stiffener isn't allwoing the chassis to absorb the bounces by flexing the body.
 

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'Tother way around. Stock springs with the very firm Koni Yellow is way too much damping for the springs. Spiders generally don't do well with yellows on the rear at all, even with performance springs. Rear tends to hop sideways a lot on bumps.

I used to cut one turn off the stock for racing, before custom made springs were available. Car got a bit too low, so you need to add spacers to get a road-worthy ride height. Learned this trick from John Shankle. IAP or other front springs are about the same.

Koni yellow at mid range on the front, reds at full soft at the rear. Keep the shortened stock springs - there are no BETTER choices, and other than a torch cut, none cheaper.

Chassis stiffener is a good addition in the Spider, not needed for the GTV.

Stiffer front roll bar. Rear sway bar is dealer's choice. Depends on how much under/over steer you like, choices range from no bar at all to Shankle's stiff one.

Robert
 

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..I took 'bounce' to mean the car went up and down on the suspension before settlin ...
I did too, but it didn't make much sense. OTOH, wheel hop should occur with stock springs and really stiff shocks as his set up was described. In both cases the car would feel pretty loose. My version of interpreting what he said. It's easier to just hop in the car and actually feel what's up. We do amazingly well diagnosing on the BB by internet braille!

Robert
 

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Sorry for the late reply (and the internet braille) - the website would't let me log back on for some reason...

YOu are both right I am referring to the car bouncing up and down on the suspension. It really feels like a harmonic frequency thing because there are just two places in town where I've noticed this, but certainly makes sense that my shock /spring pairing is to blame. If I am intent on getting less bodyroll and better handling, am I better off with my plan of cutting off 3/4 ring in front and 2 in back and finding me two pairs of original spec shocks, or am I better off with doing the same and simply switching to red Konis in back. Does the amount of spring cut off need to change if I don't have the stock shocks?

To be really clear about the chassis stiffener. It really has done what I wanted in terms of quietening the car over bumps. I probably don't notice major handling improvements because I am not driving this car on the track. THe one thing that is worth considering is that I can't get a jack under the car from the side now and need to drive it up a ramp to get under it at all. Lowering the car further....
 

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Use stock shocks only if you keep the springs stock. Cutting stock springs makes them quite a bit stiffer, and you will then benefit from the Koni's. You really should replace the yellows - at least on the rear - unless you're after a pretty stiff ride and lowered car. You can make the reds in front stiffer then normal (close to the yellows) just by tightening them a bit past middle if you need to, but you likely will not need to. Use red rears (not yellows at all!) on full soft, but 2 turns cut off the rear springs is way too much. Keep the front and rear cut about the same - around 1 turn. You could make the front sway bar a bit larger in diameter if you cut the front springs. Increase front neg camber with adjustable upper arms, and increase caster (for higher self-centering) a bit.

There are lots of little adjustments after you settle on which way you want to go with the spring - shock set-up. Take careful driving notes as you make them to find the sweet-spot for you and your car. Even changing the toe-in by 5 mm will have a noticeable effect on feel. So will widening the tires from 70 series to 60's.

Don't lower the car too much. 1 inch or less will be OK. More and you start getting bump-steer problems because of the changed geometry in the front lower arms. You can get a pretty good bump-steer kit from Alfaholics if you go that way.

Robert

Robert
 

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I have a set of 4 good used Bilsteins for the spider. From threads it looks like these would pair well with an IAP spring set. Does this sound like a better plan the cutting the stock springs thing? (I actually don't know for sure that my springs are infact stock - where do I look to tell?) Is bottoming out likely to be a concernenough to require spacers? Is a front antiroll bar still the best add-on to limit body roll (my car has a lot)?

Thanks for all the advice.

Rumi
 

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A common approach on the BB is to upgrade the springs - centerline or IAP are common. Then you usually need stiffer sway bar in front (much less often in rear). Some only replace front springs as the car handles well with the rear as soft as possible. Koni yellow set at mid range on the front and Koni red at rear on full soft. One limitation of lowering the car is that you get some "bump-steer" effect. Alfaholics and some others have a kit to counter this too. Be sure your route can take the already low oil pan being an inch lower yet! Or use spring spacers to restore normal ride height with the stiffer springs.

Wider tires will significantly affect the steering effort.

If you enjoy driving the car now, you might be disappointed with any of these changes. Alfa's are already pretty good. You'll make it different, but 'better' is very subjective. Track-like handling is not always fun on street driving, especially for a daily commuter.

Robert
Great to have all this knowledge and information but just a little too much uncertainty.

I too have gone to sports springs (I think Shankle) and Koni Reds front and rear having changed the stock springs and shocks from 1975.

The result I have now is that the front is definately lower (I think by about 1") but the rear appears to be higher now than before, wheras before the rear was sagging. So the car actully leans forward, not quite the look I wanted. The Koni's are half soft front and rear.

The ride is definately firmer on the front, maybe a little too firm, but I haven't driven it much to get used to it or to judge whether I'm happy with it.
How can I best address or adjust the ride height at the front. Are spacers the only option and are plastic one's better than aluminium.

Also, I understand that the ride height of spacers is now linear. Right now the car is lower at the front by about 1". So what can I do ? - lower the back or raise the front. Also, will making the front shocks fully soft change the ride height.
 

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"Informed" opinion is that Spiders handle better with the rear a little lower than the front. What ride height do you want? If you want to lower the rear then you probably have to cut the Springs and that will make them stiffer. Spring stiffness is approximately proportional to the number of coils. If your spring has 10 turns and you cut off 1 coil then you will increase the stiffness by about 10%.
It may be easier to adjust the front height. There are two different spring pan depths. The standard arrangement is to have a shallow pan on the driver's side and a deep pan on the passenger side. Take a look at what you have and consider swapping one or both of them.
Aluminum spacers came in three different thicknesses. The ones that I have are about .28". The effect on ride height is doubled due to the location of the spring, so one of these spacers will raise the height by about .56". It is news to me that Alfa used plastic spacers.

Hydraulic shocks have no effect on ride height but gas shocks may raise it.
 

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"Informed" opinion is that Spiders handle better with the rear a little lower than the front.
It may be easier to adjust the front height. There are two different spring pan depths. The standard arrangement is to have a shallow pan on the driver's side and a deep pan on the passenger side. Take a look at what you have and consider swapping one or both of them.
It's starting to make proper sense. I am curious as to why the rear springs that I have installed leave the car sitting a little high since they were part of a Shankle sports set, yet the fronts lower it by about 1". Would there be any value in using the stock springs in the rear ?.

However, I don't follow you when you refer to the "different spring pan depths" . How do you determine which is shallow and which is deep. Just note that my drivers side is the right hand side.

Also in relation to ride height, there have been many references on the forum that mention that in the USA the ride height was determined to conform with lighting regulations. Does that mean that Alfa made stock Spiders with different ride heights meaning that RHD vehicles had a different ride height than LHD vehicles exported to USA.
 

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I think that the shallower pan on the driver's side is to account for the weight of the driver but the fuel tank is also on that side on US cars and if the battery is under the hood then it too is on the driver's side. You should be able to see if your pans are different if you view them from the underside.

Shankle made "sport" springs and "Super Sport Springs" I tried to find a used set but I was unsuccessful. IMO are they are a good compromise between the too soft stock springs and the very stiff sport springs that are popular over here. I may be able to tell which ones you have if you measure the wire diameter. You can cut one coil off the stock springs to lower the car and gain about 10% stiffness but it will be pretty soft compared with the Shankles.

The aluminum spacers may have been used to raise the US ride height to comply with the government regulations. I don't know if non-US cars had them.
 
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