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Discussion Starter #1
I replaced the rear sway bar with a 5/8" bar last year. Replaced the front and rear suspension close to stock this year, everything but the front sway bar. I now have a noticeable oversteer above 50 mph. One suggestion is to install poly bushings on the front to stiffen it thus reducing oversteer. However, a parts guy said that unless I am running a track car, I'll get tired of the squeeking after the grease used to lub the bushings is squeezed out. Any ideas, comments? --TIA
 

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I'll get tired of the squeeking after the grease used to lub the bushings is squeezed out. Any ideas, comments?
I have poly bushings everywhere on my Spider and I have no squeaks

Your oversteer is almost certainly due to the rear sway bar. Try disconnecting it. I run with a 27mm on the front and none on the back.
 

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I've run poly on the front Milano bar for like six years. It's never squeaked.

However, isn't your root cause problem the bigger bar on the back? Why not just go back to the stock bar? Larger sway bar on a Spider rear goes against any of the suspension advice I've seen.
 

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Discussion Starter #4
Thanks all. The car is a 1972 Euro GTV. New springs (IAP), new OEM bushings everywhere except the front sway bar. 185x70-14 tires. I no longer have the original rear sway bar.
 

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You only have to disconnect one side to disable it. What have you got to lose?

To learn more read some of the discussions on suspension setup. Stiff springs often work better with no rear sway bar and a standard front bar. IAP red springs are STIFF.
 

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New springs (IAP), new OEM bushings everywhere except the front sway bar. 185x70-14 tires. I no longer have the original rear sway bar.
I wouldn't consider poly unitl you sort out the changes you're already making...

Did you ever have the original rear bar, or is the new bar a replacement for a missing one? The common advice is to disconnect the rear bar... there's not much to it anyway... If you're going with OEM bushings all-around and 185/70/14s, it doesnt sound like you're venturing far from a stock set-up other than the springs and perhaps shocks... going with a thicker bar to perhaps replace a missing part was actually going in the wrong direction...

The IAP springs themselves will lower your ride height and stiffen the set up... If you're not going to track the car, I would think the OEM is fine, but it really depends upon your driving style and what you want to accomplish... squeak or no squeak, poly will stiffen things up and make suspension movements more direct at the expense of noise, vibration and harshness.
 

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Discussion Starter #9
The car was new to me in April of 2013. I wanted to keep the car near stock for normal brisk driving - I'm over track events at this point. The original ride height was extremely tall. I couldn't see any spacers in the pans, so I opted to replace the springs. I was told that the IAP spring were near normal in stiffness, and would lower the car one inch. It did lower the car, and I can't tell about the stiffness. The 5/8" rear bar was installed because the end bushings on the original were shot. Yes, I should have replaced the end bushings. i think the bar got tossed.
 

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I couldn't see any spacers in the pans, so I opted to replace the springs. I was told that the IAP spring were near normal in stiffness, and would lower the car one inch. It did lower the car, and I can't tell about the stiffness. The 5/8" rear bar was installed because the end bushings on the original were shot.
The easiest thing to do is reinstall the stock bar and see what happens.

For a more specific (and accurate recommendation) you should search out the racers here on the BB. There are people here who've been doing suspension adjustments on GTV's for years and years.

You also might call the guys at IAP and ask their opinion. The owner, Paul, raced for years and should know a lot about his own suspension.
 

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Speaking from experience, the problem with poly sway bar bushings is that after a while they start to squawk loudly. Therefore, you have to keep lubing them, a pain after a while, as the lube doesn't stay long in the joint, the poly being relatively hard and nonabsorbent. Some don't seem to have this problem, so maybe it depends on the average weather in those areas, I don't know, but they sure can squawk in some parts of the country.

Best to stay with the original material, imo.
 

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Discussion Starter #12
Reduced the air pressure to 28 front and 30 rear. That seemed to reduce oversteer, although I was unable to conduct a thorough test. I'll also try 26 front and 28 rear, and maybe 26/30.
 

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On a three-day, 800 mile tour on back roads on southern British Columbia. First outing in "Supah" with the changed suspension.

Very Good!!!!

The car came to me with IA reds front and rear. Fronts are rated at something like 1125 #/inch. OK for some track time, but not for back roads.

Talked to David Rugh who has springs and bars made to order.

IA rears are not too stiff so they are still there.

Now have 500 fronts that keep the lower stance of the IA springs.

Removed the rear bar. I've been driving Alfas for 50 years and I've never had one that would "turn in" so quickly. It was a little unsettling. Talked to David about a stiffer front bar,

He sais "Drive it!"

A quicker turn in does not lead to oversteer.

But for my own piece of mind set the tires at 30 front and 34 rear.

This, and along with the lighter "Brembo" front brakes is the best handling setup I've had.
 

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Discussion Starter #14
I'm wondering if there is a fairly linear grip difference between front and rear as air pressure in the tires are changed say from 24/26 F/R to 26/28 F/R to 28/30 F/R to 30/32 F/R? I would imagine there would be a small change as the tire pressures go up. The reason for the question is that optimum tire pressure for tires wear I'm sure is different from optimum tire pressure for grip. And then there is tire model/size, and suspension set up. Also, what about using a 4 psi differential, e.g., 26/30 F/R, etc.? Too many variables.
 

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Take a day and try the various pressure setting, keeping in mind what has been discussed in the suspension postings about front/rear differentials. Also keep in mind that the faster you go, the more pronounced the effects will be.
 
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