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Just wondering what’s the general opinion on this. Finishing my fast road spider and not sure if i will fit it or not. Seen a lot of race cars without it and also think alfaholics dont use them (not sure).
Any opinions?

best regards
 

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I use slightly lower Eibach springs and red Konis, CN36 tires, and have my rear bar installed. I like it very, very much. Without the rear bar things will seem a little more stable, but what you're feeling is more weight shift onto the outer front tire, which slows down its ability to "turn in". The rear bar accomplishes a more equal load on the front and rear outer wheels, which in theory will give you a higher gee capacity before excess scrub takes over.

Some like the less-quick feel, as it is likely to be slightly more controllable, but I like the sense of quickness.
 

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I prefer it disconnected.
Wanna check? disconnect the links and tie the bar up and drive it.
 

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Its quite popular to remove the rear anti roll bar in the UK. I was sceptical, undid the links and have now thrown it away.
 

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As you can see by the replies, there is no one single answer. On an otherwise stock car, it likely depends on driver preference, but even a stock car can have different front end alignment, shock absorbers, and tires; all of which may affect how a rear sway bar changes the handling. Once additional suspension changes enter the picture, the presence and/or stiffness of a rear sway bar is part of the overall suspension / handling equation.

The easiest way to explore the issue is to just disconnect one end of the rear bar and drive in different conditions. For more fine-tuned variation, Alfaholics sells an adjustable rear sway bar and also use this on one of their race GT's (Depending on what race series and rules are in effect).

Wether or not you use a rear sway bar can have an affect on the understeer or oversteer of the car but remember; the only difference between these two handling characteristics is which end goes through the fence first.

Just wondering what’s the general opinion on this. Finishing my fast road spider and not sure if i will fit it or not. Seen a lot of race cars without it and also think alfaholics dont use them (not sure).
Any opinions?

best regards
 

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George, you were doing great until you got to the last paragraph! 🤣
 

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1985 Spider (D Prepared/Track/Street - For Sale!) / Mosler GTP + Alfa Project
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If you have beefy spring rates and can control them with shocks of matching bump and rebound, deleting the rear bar is an option. It will remove a redundant setting and help you lose weight. Rear weight transfer will be controlled through the rear shock/springs only.

In the opinion of an ex-SCCA mechanic: I would not delete the rear bar on a stock suspension car neither for street driving nor autocross. I can see it helping in the track if you like a wee bit more control and understeer, but if you turn in hard it will want to lift a rear wheel and will make your contact patch on both sides all wonky. I would rather have the option of disconnecting or adjusting the rear bar as needed.
 

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It may not add greatly to the thinking, but...

When we read “understeer” and “oversteer” we often leap to the mental picture (as George remarked) of a car out of control, either pushing its nose to the outside of a decreasing radius corner, or its rear end snapping out in a spin.

In the non-race-track world, we rarely encounter these extremes. For driving around on the street you’re more likely to experience the presence of a rear bar as a lightening of the steering force. A gentle pressure on the steering wheel will get a more immediate turning response, and the pressure gradient as you tighten the turn will be less than without the rear bar.

As others have noted, the suspension is a formula, not a single item. That’s why I mentioned my particular combo. My current 77 Spider is my third 115 Spider, and fourth 115 counting my 74 Berlinas. It is the only 115 Spider that I enjoy driving.

Formula:
Light weight (early bumpers)
Eibach springs
CN36
Red Konis, full soft
Rear bar connected.

Your formula will produce your own results
 
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Well, I was only talking about "Theory" since I have not personally been through the fence with either end of a car under or over steering. But, I have been close enough to, ahem, experience the difference. Although, on an autocross course, the only penalty may be to assassinate a few pylons...

George, you were doing great until you got to the last paragraph! 🤣
 
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I‘m not sure what your driving skill levels are, but from the perspective of someone who likes to exploit a car’s handling, but is not necessarily competitive at doing so, (I’m pretty stoked if I can pull off a really nice heal and toe) I will give you that perspective:
I had a “fast street“ 74 spider that I would occasionally auto cross, and at my skill level I was able to consistently go quicker in that car with the rear sway bar Installed. However, with my GTV, and the same basic set up, I was quicker without the rear sway bar, and more notably, I felt quicker. The point I am making here is first related to Don P’s comments about “feeling more controlled, but not necessarily quicker”. Although I am sure he is right, at my skill level I am able to go “my quickest” with that controlled feeling.
That said, i also think the differences in handling between the Spider and the coupe are inherent enough that in my opinion the Spider did not gain the more controlled feeling for me that the GTV did, when removing the sway bar, and that’s why i could go quicker with it.
This of course also concurs with what others have said about how subjective it is. Add in tires, wheel size, unsprung weight, etc., and this paints the clear “formula” picture also mentioned by others.

The only other thing I would add is just that IMHO, short of high-end full-on race cars, whatever you do these cars are far less the quickest handling, but rate much higher up the scale of fun handling cars, -for me, and my regular Joe skill levels at least!
 

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Spiders typically suffer from lack of rear grip when applying power when exiting a turn which results in oversteer. Getting rid of the rear sway bar reduces this oversteer.
My setup is 205/50-15 tires, Shankle Supersport springs, SPAX adjustable shocks, dropped spindle uprights and stock front sway bar. The car is about 150 lb lighter than stock and it puts down 150 HP at the wheels.
 
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