Front End Advice/Suggestions

[Frog2Spider]

I'm planing on doing the front end on my 81 this fall, and I'm wondering about 2 things. The car is summer time street driven; never raced or rallied. It has red springs with rear sway bar with 4 Koni shocks.
What are the pros and cons of nylon bushings vs rubber? I'm leaning towards the rubber, as I'm told they provide a softer, less harsh ride. Is this true?
And, for a car that enjoys some aggressive back road driving, does a front end sway bar make any favorable or negative contributions?
Your experienced input is appreciated!
Dave.

[PhillySpider]

Dunno, but I'd be interested in those Koni's if you scrap them

[DieselSpider]

With too stiff a sway bar you can end up with one tire off the road on terribly uneven pavement as it can limit the independent movement of each wheel on the same axle too much. On a low profile vehicle like the Spider its not so big a deal however on a high profile vehicle like a van it can toss you about when their too stiff.

I went way too stiff on a P30 8 ton chassis once and it was not fun since the drivers seat was literally 5 feet off the road and the truck just hugged the road like a sports car tossing you like a lookout in a crows nest on a sailing ship.

[KWL82]

http://www.suspension.com/blog/rubber-v ... -bushings/

[81SPIDERMATT]

don't think I have driven a car without a front sway bar ... cant imagine it would be anything but an improvement over one that did not have one .... rubber over poly unless you want to tell heads or tails while running over a dime ... but polys are easier to install ... konis are what everyone shoots for eventually but don't know enough to suggest red over yellow ... be sure to properly torque front end bushings no matter which you choose ( little drive to let things settle and weighting the car and having it on the wheels while you final torque them down) very important or you will twist the bushings and they wont last very long ... maybe less important with poly .. but for sure something that should be done .... alignment right after work is done ... wish I had a rear sway bar .. I hear they are great for that aggressive driving you speak of .. especially the corners ... ball joints tie rod ends and taking the slop out of the steering box if you have any should be looked at also while you are there ... great fall project for sure and you will love new stuff up there ... big difference depending on how long it has been ...Matt

[Frog2Spider]

Dunno, but I'd be interested in those Koni's if you scrap them

The Koni shocks are new, and I love them! them!

Dave

[Frog2Spider]

don't think I have driven a car without a front sway bar ... cant imagine it would be anything but an improvement over one that did not have one .... rubber over poly unless you want to tell heads or tails while running over a dime ... but polys are easier to install ... konis are what everyone shoots for eventually but don't know enough to suggest red over yellow ... be sure to properly torque front end bushings no matter which you choose ( little drive to let things settle and weighting the car and having it on the wheels while you final torque them down) very important or you will twist the bushings and they wont last very long ... maybe less important with poly .. but for sure something that should be done .... alignment right after work is done ... wish I had a rear sway bar .. I hear they are great for that aggressive driving you speak of .. especially the corners ... ball joints tie rod ends and taking the slop out of the steering box if you have any should be looked at also while you are there ... great fall project for sure and you will love new stuff up there ... big difference depending on how long it has been ...Matt

Thanks 81SOIDERMATT!
The Koni's are new and while the car only has 45,000 miles, I am going to replace all the front end components, with exception of the steering box. The car presently drives and handles great, but the PO had the car sit for 15 years and put less than 2,000 miles on it. When I bought it, all the seals leaked. All that has been corrected, except for the front end bushings, effected by the oil contamination and age.
I was wrong in my original post. The rear has a torsion bar, not a sway bar, so maybe I'm start with a rear bar, before considering a front. Good advice on torquing the bushings. Will do.
Still like to learn more about the pros and cons of nylon bushings and what to expect, if used.
Thanks again, Dave.

[DieselSpider]

If you use nylon or delrin instead of poly or rubber you can expect a very harsh response and a lot more transfer of road noise to the chassis and possibly some metal fatigue from the increased transfer of stresses and almost as bad as if you had used solid steel ones. Poly would be the hardest I would go.

[lglade]

The Koni's are new and while the car only has 45,000 miles, I am going to replace all the front end components, with exception of the steering box. The car presently drives and handles great, but the PO had the car sit for 15 years and put less than 2,000 miles on it. When I bought it, all the seals leaked. All that has been corrected, except for the front end bushings, effected by the oil contamination and age.
I was wrong in my original post. The rear has a torsion bar, not a sway bar, so maybe I'm start with a rear bar, before considering a front. Good advice on torquing the bushings. Will do.
Still like to learn more about the pros and cons of nylon bushings and what to expect, if used.
Thanks again, Dave.

The rear of a Fiat Spider has coil springs and trailing arms but not torsion bars (a type of spring). The racing Abarth Spiders might have something cool like that, but our rank and file cars did not. Replacement trailing arms are cheap and available, but it's likely only the bushings in them that are worn out.

A lot of guys have added a rear sway bar to their cars (I don't have one yet personally) and swear by the handling improvements that they make. Most of our trusty vendors have one available and can give you good advice as to whether a rear bar necessitates a bigger front sway bar.

[Frog2Spider]

If you use nylon or delrin instead of poly or rubber you can expect a very harsh response and a lot more transfer of road noise to the chassis and possibly some metal fatigue from the increased transfer of stresses and almost as bad as if you had used solid steel ones. Poly would be the hardest I would go.

Thanks DieselSpider
I meant Poly. You 'backed-up' what I've read. I like a comfortable ride, and I think rubber is the way I'll go. The originals lasted 36 years and 45,000 miles. New rubber should see me thru!

Thanks again
Dave

[Frog2Spider]

The Koni's are new and while the car only has 45,000 miles, I am going to replace all the front end components, with exception of the steering box. The car presently drives and handles great, but the PO had the car sit for 15 years and put less than 2,000 miles on it. When I bought it, all the seals leaked. All that has been corrected, except for the front end bushings, effected by the oil contamination and age.
I was wrong in my original post. The rear has a torsion bar, not a sway bar, so maybe I'm start with a rear bar, before considering a front. Good advice on torquing the bushings. Will do.
Still like to learn more about the pros and cons of nylon bushings and what to expect, if used.
Thanks again, Dave.

The rear of a Fiat Spider has coil springs and trailing arms but not torsion bars (a type of spring). The racing Abarth Spiders might have something cool like that, but our rank and file cars did not. Replacement trailing arms are cheap and available, but it's likely only the bushings in them that are worn out.

A lot of guys have added a rear sway bar to their cars (I don't have one yet personally) and swear by the handling improvements that they make. Most of our trusty vendors have one available and can give you good advice as to whether a rear bar necessitates a bigger front sway bar.

Ya, Trailing Arm! That's it!!
Thanks iglade.

[djape1977]

there's different levels of stiffness with poly bushes. i prefer softest ones which are 30% harder then rubber. ride is definitely not harsh with those.

regarding sway bars - do add a rear one, it makes a world of difference

regarding Koni shocks - waaaay overblown reputation

[Odoyle]

To comment on the discussion of poly nylon/ oe rubber, under most driving conditions, rubber bushings are the best choice. However, high performance driving demands less deflection, which a rubber bushing is not capable of providing. When the front control arm bushings deflect, the control arms can move in relation to the frame. The cornering loads cause this deflection to result in positive camber, which reduces/distorts tire patch. The net effect is a loss of a cornering power at the front. Most poly/nylon bushings offer little ability to absorb rotational shear within themselves. The only way a rigid suspension bushing can allow rotational movement is if one of the mating surfaces slides on the other. This sliding action demands close manufacturing tolerances and lubrication for satisfactory operation. Most aftermarket poly bushings do not meet those requirements. Without consistent lubrication, the urethane can stick to the steel, and the suspension does not move smoothly.

[DieselSpider]

Most of the high end poly bushings I have bought for other vehicles included a small can of Blue Molybdenum Grease to coat them with before installing them. Lubrication with the right grease can be much more critical with the poly bushings.

[Frog2Spider]

Thanks for all your input!

I now feel that with my style and level of driving that I will use the rubber bushings and add a rear sway bar.

Thanks again,
Dave.