Opinions on the Ultimate Suspension

[Dbelleperc]

What is everyone's opinions on the "ultimate suspension" for a five lug teener. Non coil over for the fronts. i.e. 935 stuff.

This is my opinion:

Monoballs Fronts, and are they available for the rears?
Bilstein Sport shocks Front and Rear with adjustable rear springs
180-200 pound springs
Plastic suspension bushings or the Elephant Racing PolyBronze
Sway bars (Antiroll Bars)
Camber Plates
Stiffer Torsion Bars
Turbo Tie Rods
Chassic Stiffening

Opinions would be great to correct any errors or what anyone would think is better.

And last but not least, for the parts what company do you think offers the best products.

i.e.
Racers Group
ERP products <- don't know who make their products
Elephant Products
I know that there is many more but I don't feel like typing so damn much.

[BigD9146gt]

David, i'm in the process of building my 9146gt replica w/3,2 motronic. The suspension i'm putting together is my opinion of the ultimate suspension.

Bilstein RSR fronts
Bilstein Sport rears
Undesided on hallow torsion bars or coil overs for front
Custom coil overs for rear (see pics)
Boxster mono blocks all around with big vented rotors (see pics)
Billet CNC adapter blocks for calipers
22mm sway bar up front, my own CNC aluminum arms and drop links (not made yet)
Rear brake bias valve in drivers compartment for easy adjustment
New bushings, zerk fittings for lubing everything
Fiskse FM10 17x8 front, 17x9.5 rear (or the biggest i can get)

[Dave at Pelican Parts]

Why use bushings at all? Go with roller bearings ("Mueller bearings") on the suspension pivot points. http://www.muellerdesignwerks.com

--DD

[BigD9146gt]

If i was going to go with different bearings, then i would go with bronze bushings. I think elephant racing has them. I'm sure mullers design works very nice, but how many factory Porsches, or high performance production cars these days use roller bearings in the suspention? Anyone? Maybe because its not cost effective. For a track only car, i'd say sure. But eveyday pot holes and speed bumps, no thanks.

[Dave at Pelican Parts]

While I haven't driven or ridden in a street-oriented car that uses the roller-bearing setup, I am told that it actually improves the ride quality. Most especially over the plastic replacement bushings, which tend to stick even when you fit them carefully.

I feel that the bearings would likely be better than the Elephant Racing bronze bushings, as they should move more freely and let the suspension actually do the work.

I believe that cost is the main reason we don't see roller bearings on street cars. And possibly NVH (noise, vibration, harshness) issues--because the rubber will absorb some of the smaller movements that the springs/shocks do not. But rubber and solid bushings (plastic or metal) offer more friction than the bearings do, so they have their own NVH issues. Most especially the metal ones.

The bearing setup is also helped by the fact that the surfaces the bearings ride on are forced to be smooth and round. On our cars, the areas where the bushings ride are usually neither.

Up to you--but if you are building the "ultimate" suspension and are considering something other than stock rubber bushings, I think the bearings deserve a very serious look.

--DD

[jhadler]

Originally posted by Dave at Pelican Parts
I believe that cost is the main reason we don't see roller bearings on street cars. And possibly NVH (noise, vibration, harshness) issues--because the rubber will absorb some of the smaller movements that the springs/shocks do not. But rubber and solid bushings (plastic or metal) offer more friction than the bearings do, so they have their own NVH issues. Most especially the metal ones.
--DD

Dave,

One other important issue though is longevity. Roller bearings and spherical bushings are great on a dedicated race car that's going to be torn down at least once a year a recieve a thorough inspection. But on a street car, things like roller bearings and spherical bearings (while remarkably improving performance ) are subject to increased wear from debris, dirt and road grime. I think that's why, beyond the cost concerns, is a driving reason to keep them out of production vehicles.

-Josh2

[J P Stein]

I thought this was a thread about the "ultimate"...yada.
I use Muellers bearings and they are sweet.... and reasonably well protected against the elements....not that it matters to me.

You're in the same box with those plastic bushings....plus. Here's a pic of a welt bushing after a couple years squeeky service. Note that the inner end is out of square. That is plastic deformation. the ID is oversize/out of round about .02-03......but it's your time/money. ......

[BigD9146gt]

JP, your right, this is the "ultimate" suspension forum... under my definition of "ultimate", i consider a streetable car that i don't have to check/clean the bushings once a year. That would be an "ulitmate" pain in the ass. Now i understand that you have had great luck with yours, and thats awesome. But consider how many thousands of polygraphite bushings get sold each year... and how many lovely days you get to drive your car in lovely Washington weather...

Dave, your right, my labor intensive efforts to get my plastic bushings to not bind are close to pointless. If i were to do it all over, i would build my own A arms,and receivers like the ones pelican sells.

[jhadler]

Originally posted by Dbelleperc
What is everyone's opinions on the "ultimate suspension" for a five lug teener. Non coil over for the fronts. i.e. 935 stuff.

This is my opinion:

Monoballs Fronts, and are they available for the rears?
Bilstein Sport shocks Front and Rear with adjustable rear springs
180-200 pound springs
Plastic suspension bushings or the Elephant Racing PolyBronze
Sway bars (Antiroll Bars)
Camber Plates
Stiffer Torsion Bars
Turbo Tie Rods
Chassic Stiffening

Okay, getting back to the topic of what is "the best"... :-)

Monoballs in front? Sure, any kind of spherical bearing for the strut would be great. It doesn't specifically have to come from Elephant, or Weltmeister, or whomever, but the principle is to eliminate unwanted flex in the strut motion. As for the rear? There's little need for 'em. The shocks in the rear are not having to deal with the same kind of loads that the front is. But sure, some kind of spherical bearing back there would be way cool.

Shocks...Bilstein? If you're talking "ultimate", then Bilstein doesn't even make the first cut. Bottom shelf, Konis. Next, double adjustable Konis. From there you go up into the heady world of Moton and Pensky shocks. Cost more than many 914's...

Springs? I think 200# rear springs matched with 21mm torsion bars (and a 22mm front sway bar) makes for an excellent handling 914, and still tollerable on the street. But it's all a matter of application. What do you want the car to do? If it's a road racer, you'll probably want more spring rate than that. If it's a grocery getter and nothing more, you might want to soften it up a bit. You see where I'm going I hope...

Sway bars? Front needs a good bar, but unless you've got a LSD, a rear bar might be more trouble than it's worth. Sway bars couple the suspension motion to the chassis roll. If you compress one side, the other will extend. This often leads to wheel spin when you start going up in spring rates.

Other stuff... Camber plates? Yeah, whatever will work, if you're really into it, you get teh really cool camber/caster plates that replace the tops of the strut towers, but that gets into the big money again. The other stuff gains you a little, and in some cases that might be enough. Tie Rods? Anything to reduce unwanted suspension motion is good. Replace all those rubber joints with less flex.

Chassis bracing? Sure, the best place to start is the rear suspension pickup points. The inner tabs of the trailing arm mounts are the most susceptable to flexing, but the best thing to do is to make a semi-tube frame out of the car... :-)

Anyway, there's my $0.02...

-Josh2

[Brant]

I've got more Ideas.....

-Its possible to chassis drop the car by cutting the front struts and then running custom shocks with custom valving...
-On the rear, there are some nice custom set ups with inverted shocks and coil overs.. shorter shocks with custom valving... (Carrera shocks come to mind)
-chassis bracing... What Josh said.. On the inside of the trailing arms is the most important brace of the whole car.. I've ripped mine out twice before I realized how important this was. The good braces are adjustable.
-Also, there are some people out there building adjustable toe bracing. The brace uses a joint that allows you to adjust the toe and then lock it down so that it can not change.. This type of bracing reportedly will NOT work with poly bushings... too much side flex in poly bushing to hold the toe. There are lots of mono-ball bushings out there.. plus rollers.
-Chris Foley and other race shops are raising suspension points to allow a car to be very low without messing up the range of motion in the suspension.... I don't/can't do this, but I'd sure like to....

A truly Ultimate suspension would probably disregard all of this old technology and run custom double a-arms or something...

brant

[Porschekid962]

Ultimate? Unequal lenth and non parallel A arms front and rear. Coilovers operated by pullrod links, lower CoG and reduces squat when on power.

Ultimate street car suspension, RSR valved bilsteins, JRZ, Fox, Bilstein coilovers in the rear, I think the elephant poly bronze bushings are great, my dad has them on his 74 911 and they are very easy to lube up and give much more feel than plastic. Ditch the torsion bars if you want in the front and bolt in a 935 suspension if you have the money or go with 911 front suspension. Sway bars, hollow of course and SRP sells the nicest I have seen.

[BigD9146gt]

Originally posted by Porschekid962
Coilovers operated by pullrod links

Cool idea if the car was an open wheeled car... but not needed for covered wheel cars.

[mike mueller]

hiem-joint suspensions for street cars are not too ideal....the joints have a short life time...I have one customer with a street/track 3.8 911 that removed his 935 type front suspension and replaced it with stock a-arms and my needle bearings...very happy guy now I was told at a swapmeet that the 904's used needle bearings in the suspension...I have not confirmed this, nor have I really tried, LOL

front coil-overs really only give you more choice in spring rates than torsion bars (for most people, the available torsion bars are fine) and they make it a "little" easier to adjust the ride height if you need to make large adjustments.

[jhadler]

Well, the "ultimate" suspension that I've seen for a full-bodied car was, well... not really a full bodied car anyway. It was basically a formula car, with SLA suspension front and rear, and fiberglass "shell" of a 914 suspended over it. Really cool, REALLY expensive.

-Josh2