Neon Suspension Information

3.1 Base Suspension (SDA)

The Base suspension package (sales code SDA) was only available on 1995 m/y Base Neon Sedans with manual transmission and without air conditioning.  Ordering either the automatic transmission or A/C included an upgrade to the Touring suspension (SDC).  The SDA suspension was discontinued for the 1996 m/y.
 
Base (SDA) Suspension Specifics
Spring Rate (Front) 150 lbs/in
Spring Rate (Rear) 120 lbs/in
Front Sway Bar none
Rear Sway Bar none
Steering Ratio 22:1 (manual)
Struts Stiffer

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3.2 Touring Suspension (SDC)
The Touring suspension package (sales code SDC) is standard on most Neons.  It is used on all Highline, '96 Base, all Sport Sedan, '97 and newer Sport Coupe Neons.  This is the softest package, but is still quite effective on the autocross course.
 
Touring (SDC) Suspension Specifics
Spring Rate (Front) 140 lbs/in
Spring Rate (Rear) 120 lbs/in
Front Sway Bar 20 mm
Rear Sway Bar none
Steering Ratio 18:1 (power assist)
Struts Stiff

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3.3 Sport Suspension (SDE)
The Sport suspension package (sales code SDE) was originally used for '95-'96 Sport Coupes only, not Sedans.  It was discontinued for the 1997 m/y when the Sport line became an option package on the Highline car.  However, the SDE package returned for '98-'99 on R/T Neons, both Coupe and Sedan.  It has stiffer struts than the Touring setup, a rear swaybar, and a heavier front swaybar.  In addition, it has taller front jounce snubbers, which provide additional spring rate.  Many people consider this the best suspension for mixed street and autocross use, since it is stiffer than the Touring but not as harsh as the Competition package.  It also has a slightly quicker steering ratio.
 
Sport (SDE) Suspension Specifics
Spring Rate (Front) 150 lbs/in
Spring Rate (Rear) 120 lbs/in
Front Sway Bar 22 mm
Rear Sway Bar 16 mm
Steering Ratio 16:1 (power assist)
Struts Stiffer

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3.4 Competition Suspension (SDK)
The Competition suspension package (sales code SDK) is only available on ACR Neons, and is the same for both Coupe and Sedan.  It is similar to the SDE suspension, with one major difference.  The main feature of the SDK package is very stiff struts for improved track and autocross handling.  The '95 and '96 m/y ACRs had Arvin struts with adjustable camber.  '97 and newer m/y ACRs come with Koni struts that have adjustable rebound damping, to allow tuning of the car's suspension response and over/understeer tendencies.  '97 and early '98 ACRs were also adjustable for camber; however, this was discontinued due to chronic dealer misunderstanding of ACR alignment requirements.  Camber is discussed more fully in the Q&A section of this page.

In addition to the struts, the Competition package includes heavier hubs to withstand high cornering loads.  Early '95 m/y ACRs had the standard hubs, which cannot hold up to sustained competition use.  The revised hub has a 2mm thicker flange, making it 10mm.  This was addressed by a TSB, which called for warranty replacement of the thinner hubs.  The new part (p/n 4670292, $97.50) was incorporated as a running change during the '95 m/y, and includes slightly longer wheel mounting studs to allow for increased flange thickness.
 
Competition (SDK) Suspension Specifics
Spring Rate (Front) 150 lbs/in
Spring Rate (Rear) 120 lbs/in
Front Sway Bar 22 mm
Rear Sway Bar 16 mm
Steering Ratio 16:1 (power assist)
Struts Very Stiff; Adjustable

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3.5 Export Suspension (SDF)
The Export suspension package (sales code SDF) is very similar to the Sport suspension.  Strut damping is slightly changed to accomodate European ride and handling expectations, and to take advantage of higher speed-rated tires furnished on export Neons.
 
Export (SDF) Suspension Specifics
Spring Rate (Front) 150 lbs/in
Spring Rate (Rear) 120 lbs/in
Front Sway Bar 22 mm
Rear Sway Bar 16 mm
Steering Ratio 18:1 (power assist)
Struts Stiffer

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3.6 Suspension Questions and Answers:

3.6.1    Q: What are Camber, Caster, and Toe?
A:    Camber, caster, and toe are terms used to describe various alignment settings:

Camber is the angle of the vertical axis of the wheel, measured perpendicular to the centerline of the vehicle.  Camber is adjustable on ACRs and can be modified for adjustability on other Neons.  Negative camber indicates that the tops of the wheels are tipped in toward the centerline of the car; positive camber means that the tops are tipped out.  See the discussion on camber adjustments below for more information on this subject.

Caster is the angle of the vertical axis of the wheel, measured fore-and-aft, parallel to the centerline of the vehicle.  This influences steering effort and tendency of the steering to self-center, and is not normally adjustable on the Neon.

Toe is the angle of the horizontal axis of the wheel, measured relative to the centerline of the vehicle.  Toe is adjustable on all Neons.  Toe-in (positive) means that the wheels are pointed slightly toward each other as the car rolls forward; toe-out (negative) means that they are pointed away from the centerline.  See the discussion on alignment settings below for more information on this subject.

 3.6.2    Q: Why should I adjust camber?
A:    Stock alignment settings call for 0 degrees camber; i.e. the wheels theoretically sit perpendicular to the ground when the car is at curb height.  As the car corners, the load is placed most dramatically on the outside front tire.  This causes the tire to deform such that the contact patch is no longer firmly planted in the middle of the tread area, but drifts up onto the outside edge of the sidewall, and unloads the inside edge of the tread.  Compliance, or give, in the suspension components can amplify this effect.  The net result is that the cornering grip of the tire is reduced, and the tire slips.

Adding negative camber to the wheel means the loading is biased toward the inside edge of the tire.  Consequently, when the car turns, the outside front tire sits squarely on its contact patch due to the negative camber "correcting" for the cornering load.  Grip is increased, and the car will turn more precisely at higher speeds.

Camber can be adjustable at all four wheels, but I personally recommend against adding negative camber to the rear wheels.  The Neon, like most FWD cars, understeers.  Adding negative camber to the front increases grip, thus decreasing understeer and providing more balanced handling.  Subsequently, adding negative camber to the rear will increase understeer.

Negative camber can cause wheelspin for drag racers, and is not necessary since under drag racing conditions the car is evenly loaded from side to side.  Radically negative camber (-3 degrees or more) can also lead to wheelspin on the inside tire during autocross maneuvering.
 

3.6.3    Q: How can I adjust camber on my ACR?
A:    Camber, as stated above, is easily adjustable on '95-early '98 m/y ACRs, and other models can be modified to allow adjustable camber.  The struts on ACRs listed above have slotted mounting holes, and eccentric or "cam" bolts.  With the bolts loose, the struts are adjusted in or out to set desired camber. The bolts are rotated so that the eccentric lobe holds the strut in position, and then torqued to 150 ft/lbs.  There should be a tick mark on the bolt - this indicates maximum negative adjustment when rotated toward the centerline of the car.  Additional camber can be gained by loosening the upper strut bolts and pushing the top inboard.  The SCCA-mandated maximum camber is -2.4 degrees.

Most '98 and all '99 ACRs do not have the slotted holes.  Adjustment is possible to these cars (and SCCA-legal) by slotting the holes with a grinder, providing the dimensions of the original slots are not exceeded.  If the holes are slotted, the round bolts should be replaced with the ACR-specific cam bolt package (p/n below).  See a detail from the diagram previously published in Mopar Performance News.
 
Item Part Number Quantity
Cam Bolt (Lower Clevice bolt) 6500614 one/side
Top Clevice Bolt 6500615 one/side
Nut 6500593 two/side
Dogbone Washer (on nut side) 4014444 one/side

When these are installed, the dogbone washer and nuts face the front of the car. (This line coutesy of Jeff Ball.)

3.6.4    Q:How can I adjust camber on my Neon?
A:    Other Neons can be modified to allow camber adjustment in several ways.  The struts can be slotted as above; however, this is not SCCA-legal (in Stock classes) for non-ACR Neons.  Another method, which is permitted for all Neons, is the use of the Mopar Camber Adjusting Bolt Package (front bolt p/n 4762135, about $20 for two).  These are also known as "crash bolts" because they are used to bring damaged cars back into alignment spec.  Crash bolts are round and slightly smaller in diameter than the originals, which allows the adjustment.  One bolt in each strut will allow approximately -1 degree of camber.  To get near the SCCA-mandated maximum of -2.4 degrees, you will need two bolts (top and bottom) in each strut.    Additional camber can be gained by loosening the upper strut bolts and pushing the top inboard.

The crash bolts, being smaller than either cam bolts or the regular knurled bolts, should only be torqued to 140 ft/lbs.  Torquing them any higher will stretch the bolts.  Consequently, they are unable to generate the clamp load of the originals, and may slip under autocross conditions or with race tires.  They should be acceptable for street use, however.  I drive approximately 18,000 vigorous street miles a year, and have not experienced any slip in camber using the crash bolts.

There is an improvised fix to prevent crash bolt slippage that seems to work even for autocross:  simply paint the lower strut clevice before installing the crash bolts, then tighten them down while the paint is still wet.  Once dry, the paint adds enough friction to prevent slipping.  Using contrasting colors will also highlight any slip that does occur.  (This fix developed by Bud Collins and Phil Osbourne.)

As stated above, I recommend against negative camber at the rear.  However, alignment settings are very much a matter of personal preference.  Different rear crash bolts (p/n 4773957, about $16 for two) are available; two bolts are required per wheel.  Note that putting the nut forward on the top bolt makes access easier for disc brake cars, since the caliper is not in the way.  (Rear crash bolt information and tips courtesy of Jeff Blankenship.)
 

3.6.5    Q: What are suggested alignment settings?  Will they hurt my tires?
A:    Many people have differing opinions based on their driving style, what they do (street, autocross, track), and other factors.  Here are some suggested settings with which to begin; these can be adjusted as you become more in tune with the car.
 
Spirited Street Camber Toe (total)
Front -.5 to -1.5 deg 1/16" in (+.25 deg)
Rear zero zero
Competition Camber Toe (total)
Front -2 to -2.5 deg 1/16" in (+.25 deg)
Rear zero to -.5 deg zero

I personally run the "competition" setup on both my daily drivers, year round, with no noticeable wear problems.  Contrary to popular belief, excessive toe is what causes uneven tread wear, not camber.  Negative camber will in fact promote good tire life by distributing the load evenly across the contact patch when cornering.

In support of the listed specs, here are the words of a very successful Neon racer.  This is paraphrased both from an article in Grassroots Motorsports, and posts to the Neon message boards:

"Here we go again!   When I talk camber values, they are absolute, not relative to the front.  Negative rear camber will increase traction at the rear.  This is why it will increase understeer.  This is why we club racers run 8-10 psi MORE air pressure in the rear than the front... to decrease traction at the rear and have good balance.  I am resending my toe essay from a long time ago for the handling neophytes on the list.  BTW no one has given a good reason to run toe out on the front yet.

To evaluate toe on the front, what happens when you toe out the rear?  The car oversteers.  This is because the outside, more heavily loaded tire (the tire with the most influence on cornering) is pointing towards the outside of the corner.  This steers the rear outward and brings the back end out relative to the front.  Use that fact at the front, and you see that toe out (more than Ackerman) steers the front towards the outside of the corner.  This equals understeer which I don't think you want to do.  Some people use toe out, whether they think it or not, to stabilize the car (understeer).  In autocrossing, the car is usually never completely steady state, and the understeer at the front makes it more forgiving.  If people run toe out at the rear, this destabilizes the car.  Then they dial in front toe out to compensate, whether they think it or not, for the instability.  I would not recommend running any toe out at the rear of the Neon either.  It has a fair amount of dynamic toe out due to bearing and bushing compliance.  Static toe out ends up giving you way too much dynamically.

Another reason for not running toe out on the front of a Neon is toe compliance from acceleration.  The Neon has a negative scrub radius in the front geometry.  This means that the center of the contact patch is inboard of the center of steering rotation.  Altering the offset of the wheels from 40mm, by the way, screws this all up.  Under acceleration, the front wheels of a Neon toe out.  Running static toe to my settings then gives you 0 toe dynamically under full throttle at peak torque in 3rd gear, minimizing scrub and optimizing speed on the straights.  Another reason for running toe in is that it is not uncommon for the camber to slip in the positive direction at the clevice bracket due to cornering loads (make sure you torque the clevice bolts to 150 ft-lbs).  When the camber setting goes positive, your toe goes out.  Take the wheel off, look at the suspension, and you'll see.  If this happens at an event when you can't reset the alignment, you end up with more toe out than you set.  So if you start toed out, you get tons of toe out.  If you start toed in, you go through zero to some toe out as it slips. Anything more than 1/8" toe out per side significantly slows the car down on the straights. We've tested it.

Everyone seems to run toe out because other people do who beat them.  Do you have a good reason to run toe out in front?  I'd like to hear it.

Whew! long post.  Hope this helps."

- Erich Heuschele
 

3.6.6    Q: Are any other alignment adjustments possible?
A:    "It is possible to shift the crossmember around and somewhat alter cross camber and caster.  It is, however, net build like the camber on non-ACRs.  Net build does not necessarily mean the setting isn't adjustable if you get creative.  It just means there isn't a screw or cam you can turn to change it easily.  Caster typically runs on the low end of the spec on Neons.  There is always some variation in the location of the strut towers when the body is built up.  Also, if you get more negative camber out of one side than the other, the crossmember can be shifted to balance it out."

- Erich Heuschele
 

3.6.7    Q: How can I lower my Neon?  What are the side effects?
A:    Neons can be lowered by using shorter, progressive-rate (or higher-rate) springs.  Lowering kits are available from Eibach, Progressive, Jamex, and other aftermarket suppliers.  Eibach's kit reduces curb height by about 1 inch; others as far as 1-3/4 inches.

Lowering a Neon may look cool, but it will have repercussions in ride and handling.  Ride is a matter of personal preference.  However, handling is compromised by lowering the Neon -  they just don't have the jounce travel to waste.

The Neon has relatively short strut travel, which means the stock springs are fairly short and stiff.  This is one of the reasons that even base Neons have such crisp, enjoyable handling.  Reducing the travel even further means that the car hits the jounce snubbers (which in fact are designed to be helper springs) more frequently.  This impact reduces the grip of the tires, as the car bounces rather than absorbing the bump.  Lowered Neons tend to understeer more than usual due to this effect.  They are also more apt to make a sudden transition to oversteer at the limit.  Neither effect is a good thing.

Handling can be maintained by going to a coil-over strut setup, in which the jounce travel remains the same, but the spring perches can be adjusted to allow a lower ride height.  These kits are available from Mopar Performance, Carrera, Tokico, Koni, and others, but tend to be substantially more expensive.
 

3.6.8    Q: How can I improve handling of my Neon?
A:    Neons handle quite well straight out of the box.  However, there are a number of (relatively) easy ways that handling can be improved:
1)    Put on better tires.  This is the place to start, and makes a never-ending discussion topic all by itself.  Everyone agrees that the stock Goodyear rubber is chosen strictly for its quietness, not perfomance.  Unless you are a driving enthusiast, it may not be worth replacing the OEM tires before they're worn out.  But when you do replace them, much better tires are available for the same price (or cheaper) than the Goodyears.  See the questions on wheels and tires below for more information.

2)    Dial in some negative camber on the front wheels.  See the question about camber adjustment for more information.

2)    Install Mopar SDE (or aftermarket) swaybars.  The SDE suspension (see above for applications) comes with a 22mm front swaybar and a 16mm rear bar.  Cars other than '95-'96 Sport Coupes, R/Ts, and ACRs benefit from this installation.  See the question on swaybars below for more information.

3)    Install polyurethane bushings in place of the OEM rubber units.  These are available from Mopar Performance, Energy Suspension, Eibach, and others.  Poly bushings stiffen up suspension response, and have less compliance than the softer rubber pieces.  This means more taut handling, and less dynamic change to alignment settings.  Note that at least some Neons (R/Ts and ACRs) changed to polyurethane bushings for certain suspension components in the 1998 m/y.  Below are part numbers and the blurb from the MP catalog (courtesy of Jim Waleke):

"All Mopar Performance bushings are manufactured of a tough and durable polyurethane which gives the bushings higher durometers than the production rubber units. The added stiffness can make the part stronger but the real advantage is that the increased stiffness increases the control of the part which can improve vehicle handling in race situations. These bushings are recommended for circle track, solo, and road racing applications. They can also be used in drag racing where they apply."
Item Part Number Price
Strut Rod Bushing Kit P4876424  36.50
Control Arm Bushing Kit P4876425 57.50
Front Sway Bar End Link P4876426 21.00
Rear Sway Bar End Link P4876427 10.75
Front Sway Bar Bushing P4876428 13.50
Rear Sway Bar Bushing P4876429 13.50
Tie Rod End Dust Boot P4876430 4.75
Rear Control Arm Bushing Kit P4876557 41.75
3.6.9    Q: What are the stock wheel/tire sizes?
A:    Most Neons come with the 14"x5-1/2" steel wheels with a 5-bolt x 100mm circle.  The alloy wheels for Sports, ACRs, and R/Ts are 14"x6" with a 5-bolt x 100mm circle.  Most of these cars have 185/65-HR14 tires, except ACRs, which usually come with 185/60 or 175/65-HR14 tires.

Throughout the '95 m/y, Base and Highline Neons had a 13"x5" steel wheel with a 4-bolt x 100mm circle.  The 13" wheel was discontinued for the '96 m/y and newer models.  The tire size is 165/80-R13 for the Base, and 185/70-R13 for the Highline.

Some early '95 m/y cars came with 4-bolt, 14"x5-1/2" steel wheels with a 4 x 100mm circle.  These were standard on Sport Sedans (with wheelcovers), and optional on the Base and Highline.  A running change was made to the 5-bolt wheels in August of '94, and alloys became standard for the Sport .

All OEM wheels have a 40mm offset.  Offset is the distance from the mounting plane to the centerline of the wheel.  A smaller offset will move the wheels outboard;  a larger offset will move the wheels inboard. Too much change either way may cause clearance problems with wider tires.  Anyone considering aftermarket wheels should keep the offset as close to 40mm as possible, since this dimension is engineered into the steering geometry.  Also, altering offset by more than 1/4" (about 6mm) is illegal in SCCA stock classes for autocross.
 

3.6.10    Q: What tires/wheels should I get?  I want to stay at the stock wheel size.
A:    The stock Eagle GAs don't exactly suck, but they are definitely chosen to be smooth and quiet, with little thought for handling performance.  At replacement time, much better tires can be had for the price of the Goodyears, which aren't particularly cheap.  Tires of softer tread compound or different tread pattern can provide improved handling, sometimes at the cost of tread life or winter performance.  Tires with a higher speed rating often improve handling due to their stiffer sidewall.  Below is a chart of some recommended tire selections:
 
Recommended Replacement Tires
Manufacturer Model SR Price Remarks
Dunlop D60A2 H $ 55 Popular, good wet/dry grip
Pirelli P6000 SV H $ 68
Yokohama AVS-I V $ 88 Grippy but short-lived
Yokohama AVS-I Z $ 122 205/55-ZR14 (rare size)
Goodyear Eagle Aquatred H $ 84 Better than Eagle GAs
Bridgestone Potenza RE930 H $ 63
BF Goodrich Comp T/A HR4-2 H $ 56
Notes:

- SR is Speed Rating.  See question below for more information.
- Price is approximate per each cost, excluding mounting.

Also, slightly wider tires can be fitted, which improves grip, except in snow conditions.  A wider tire should be coupled with a lower profile height in order to keep the overall diameter close to stock.  See the question on tire designations below for more information.  Below is a chart (tire information and calculations courtesy of Kevin Smith) of common tire sizes for the 14" wheel:

 
Common 14" Tire Sizes
Tire Size Total Hght
Whl / Tire
Sidewall
Height
RPM
(mile)
Error
(%)
Error 
(60 mph)
Remarks
185/65-R14 23.47" 4.73" 859 0% 60.0 OEM size
185/60-R14 22.74" 4.37" 887 -3.2% 58.1 ACR OEM size
195/50-R14 21.68" 3.84" 930 -8.3% 55.0
195/55-R14 22.45" 4.22" 899 -4.5% 57.3
195/60-R14 23.21" 4.61" 869 -1.1% 59.3 Recommended
205/55-R14 22.88" 4.44" 882 -2.6% 58.5 Hard to find
205/60-R14  23.69" 4.84" 852 +0.9% 60.5
Some notes to remember:

- Actual sizing varies slightly by manufacturer, just like shoe sizes.
- RPM in this case is revolutions per mile (at the wheel, not the engine).
- Error is the actual speed at 60 mph indicated.
 

3.6.11   Q: What wheels / tires should I get?  I want to move up in size.
A:    Larger wheels and ultra-low profile tires look cool, but as with lowering, there will be side effects as well.  Large diameter wheels have a lot of mass at the rim, which wastes engine muscle to get rotating.  Also, a large wheel/tire combo often ends up taller than stock in total height, which changes the final drive ratio of the car.  This leads to slower acceleration, as well as speedometer error.  Lastly, big rims with low-profile tires tend to wander, rather than track straight, as they are influenced by waves and bumps in the road surface.

From the Grassroots Motorsports "Project C-ReX" article:

"... we decided to go with only 15-inch wheels (instead of something huge like 17s).  This way we got some cool looks without throwing all of our handling and street manners out the window.

Since big wheels are heavier than smaller wheels, a little common sense guided our decision.  If it takes a 400 hp Corvette to spin a heavier 17-inch wheel, what's going to happen when we put some on our CRX? Exactly - bog city."

However, stepping up to a 15-inch wheel should minimize a lot of the problems, and it increases the choice of tires substantially.  15" x 7" wheels can bit fitted without clearance problems.  Remember to find wheels with the same bolt pattern and offset as stock (see above).  The offset can be decreased to 35mm with a 7" wheel to allow wider tires to be fitted without inside clearance problems.

Numerous sport tires from Dunlop, Michelin, Pirelli, Goodrich, Yokohama, and others are available in a minimum size of 15 inches.  Below is a chart (tire information and calculations courtesy of Kevin Smith) of common tire sizes for larger wheels:

 
Common 15", 16", and 17" Tire Sizes
Tire Size Total Hght
Whl / Tire
Sidewall
Height
RPM
(mile)
Error
(%)
Error @
60 mph
Remarks
195/55-R15 23.44 " 4.22 " 860 -0.1% 59.9
205/50-R15  23.07" 4.04" 874 -1.7% 59.0
205/55-R15 23.88" 4.44" 845 +1.7% 61.0
215/50-R15 23.46" 4.23" 859 0% 60.0 Front only
205/45-R16 23.26" 3.63" 867 -1.9% 59.5
205/40-R16  22.46" 3.23" 898 -4.5% 57.3
205/40-R17 23.46" 4.22" 860 -0.1% 59.9
Some notes to remember:

- Actual sizing varies slightly by manufacturer, just like shoe sizes.
- RPM in this case is revolutions per mile (at the wheel, not the engine).
- Error is the actual speed at 60 mph indicated.
 

3.6.12   Q: I'm confused about all those tire designations.  Little help please?
A:    Modern tires follow a standard size and duty rating system.  For instance, the common OEM tire is a 185/65-HR14.  This breaks down as follows:

185 = Width of the tire's cross section in millimeters.  Measured from sidewall to sidewall, not across the tread.
65   = Aspect ratio; the sidewall height as percentage of the section width, i.e. 185mm x 65% = 120.25mm.
H    = Speed rating (varies).  Each letter corresponds to a maximum sustained speed the tire can tolerate.
R    = Radial.
14   = Rim diameter in inches.

If you increase the tire's width, you should reduce the aspect ratio to maintain a total height that is close to stock.  Changing the overall height (diameter) of the wheel/tire combination changes the circumference.  This affects the acceleration of the car, as well as the accuracy of the speedometer, as indicated in the tire size charts above.

The speed rating indicates the maximum speed the tire can tolerate.  Sustained high speed causes tremendous heat buildup in the tire, and exceeding the speed rating can cause the tire to fail at high speed.  Not a good thing.  Heat buildup is caused by internal friction as the tire flexes while rolling.  Tires with a higher speed rating typically have a stiffer sidewall to reduce flexing; as a benefit, stiffer tires handle more crisply than tires with a softer sidewall.  The speed rating designations are as follows:

Q = 99 mph (160 km/h)
S  = 112 mph (180 km/h)
T  = 118 mph (190 km/h)
U = 124 mph (200 km/h)
H = 130 mph (210 km/h)
V = 149 mph (240 km/h)
Z = 149 mph (240 km/h and over)

One additional designation is the UTOQ rating.  This is a measure of the service life of the tire, based largely on the estimated tread life.  In general, tires with a lower UTOQ use a softer tread compound, offer more traction, and have a shorter lifespan.  For instance, the ultra high-performance Yokohama AVS-I has a UTOQ in the 100s, and an expected street life of 10,000 to 15,000 miles.  On the contrary, a consumer-oriented tire like the Goodyear Invicta has a UTOQ in the 300-400 range, and can last 50,000 miles or more.  However, handling and traction are substantially compromised in exchange for extended mileage.
 

3.6.13   Q: What are the differences between the Arvin and Koni ACR struts?
A:    Paraphrased from an article in Mopar Performance News:

"The Koni rebound rate has a 100% adjustment from soft to hard, and it straddles the ACR Arvin strut setting.  In compression, the rates were changed to respond to different piston speeds.  At slow and medium piston speeds (body roll, etc.), the valving is stiffer than the Arvin ACR strut.  At fast piston speeds (impact from bumps), the Koni valving is softer than the Arvin ACR valving. "

- Erich Heuschele
 

3.6.14   Q: What are swaybars and how do they improve handling?
A:    A swaybar is a steel rod that goes from strut knuckle to strut knuckle across the car.  It is attached with rubber or poly bushings to each knuckle, and to the frame, where it is held in place but able to rotate slightly.  The swaybar transfers load from one side's wheel to the other, which reduces body roll as the car corners.  For instance, in a right hand turn, weight transfers to the left side of the car, and the left side suspension compresses.  The swaybar transfers some of that compression to the inside (right) wheel, distributing the load more evenly, and reducing body roll.  This stabilizes the car, and helps prevent the inside wheel from locking up under braking, or spinning under acceleration.

While a swaybar does improve balance and handling, it does not increase available traction.  Better stability is achieved at the cost of some overall traction.  Consequently, handling can be balanced from front to rear by adjusting the stiffness of the appropriate swaybar.  A stiffer bar at front or rear will cause slightly more slip at that end of the car.

There are two main swaybar setups available on the Neon (excluding the stripper '95 m/y base sedan, which has none):  20mm front/no rear bar, found on most Neons, and the 22mm front/16mm rear setup, which is found on some Sport Coupes, all ACRs, and all R/Ts.  See suspension codes SDE and SDK, above, for more information.

The 22mm/16mm combination is more neutral in handling than the 20mm/0, as the added rear bar increases oversteer to counteract the Neon's inherent FWD understeer.  It is possible to use the 20mm bar with the 16mm rear bar.  In fact, this is the hot setup among autocrossers since it helps rotation in tight corners.  However, it increases oversteer noticeably.  For the average street driver, the car may be slightly prone to spin under emergency maneuvering with the 20/16 combination.  In fact, many top autocrossers are switching *back* to the 22/16 setup.

Swaybars are an easy and recommended upgrade for anyone with the SDC  suspension, who are the majority of Neon owners (or those few SDAs).  Genuine Mopar parts can be ordered through any dealer, at a cost of around $150 total.  Also, aftermarket kits are available from Eibach and others; some include even stiffer bars than the factory parts.  See the How-To section of this site for information on installing the Mopar swaybars.

3.6.15   Q: Is there a difference in the springs between each suspension type?
A:    The OEM front springs come in two different rates (140 lbs-ft and 150 lbs-ft); all rear springs are 120 lbs-ft.  However, while there are just a few rates, there are many differing free heights for the original springs.

Differing-length springs of the correct rate are used to ensure that all Neons have a consistent ride height, regardless of the equipment level of the car.  For instance, my Sport Sedan with automatic and cruise control has a substantially heavier left front corner weight than a 5-speed Highline.  Even though the spring rate is the same, a slightly taller spring is used on the heavier car to allow for additional compression.

The assembly line uses a computer program to select the correct-height springs for the equipment level of the car being assembled.  However, this program originally contained errors, which led to many '95 and early '96 m/y Neons shipping with a ride height noticeably lower than spec.

Also, it is possible to tune the handling of your Neon by trying springs with varying free heights in order to balance the cross weights.  However, this is probably illegal in most SCCA competition.

Note that the "competition springs" sold in the Mopar Performance catalog are just the regular 150/120 lb/in springs.  The units offered are the shortest free height spring available for each corner; they will lower some later cars by a little less than 1".   This is because the '98 and '99 m/y ACRs were somewhat heavier, due to the discontinuance of the Base model (earlier cars will not be lowered noticeably).   There are additional Mopar Performance products with greatly increased stiffness; however, these may or may not be SCCA-legal depending on the current state of the approved Neon trunk kit.  See the table below for part numbers and spring rates.
 
Item Part Number Rate
ACR spring (front) 5007001 150 lb/in
ACR spring (rear) 5007002 120 lb/in
High Rate (front) 5007003 225 lb/in
High Rate (rear) 5007004 185 lb/in
Extra High Rate (front) 5007005 310 lb/in
Extra High Rate (rear) 5007006 230 lb/in

3.6.16  Q: My Koni struts have oil on them.  Are they leaking?
A:    The Koni struts on '97 m/y and newer ACRs may appear to leak, with small amounts of oil collecting on the strut barrel.  Below is the text of a flyer included with the Koni struts:
"During lift inspection/servicing/tyre rotation, etc., a thin film of oil and dust collection may be noticed on the outside damper tube.  This is a normal condition which occurs during the damper internal seal 'break-in' period and does not affect the performance of the damper and does not indicate the need for damper replacement.  Damper replacement should only occur if the damper oil leakage is sufficient to cover the entire damper tube and has 'dripped' onto the lower control arm or onto the pavement during overnight parking."
Note that some owners have experienced leaking struts.  A substantial amount of oil could indicate a problem, and should be checked.  Damping ability will be reduced if the strut has lost oil; testing the strut next to a known good sample can verify correct operation.
3.6.17  Q: Why was the camber adjustment taken out of newer ACRs?
A:    The ACR option package originally included dealer alignment to customer specifications, since Chrysler assumed that ACR buyers would want the car set up to their preferences.  ACRs shipped from the factory unaligned.  However, many ACRs were sold to unknowing customers by ignorant dealers, and were delivered with no alignment corrections.

Consequently, many of these ACRs came back to the dealer for alignment to be performed as a warranty service.  Chrysler got tired of paying dealers twice for being stupid once, and the camber adjustability was dropped at the request of the Warranty Claims department.

Some very early-build '98s received the slotted OEM Konis; however most '98s and all '99 ACRs do not have slots.

3.6.18  Q: I'd like to hear some more discussion about toe-in versus toe-out.
A:    In addition to the static toe setting, the toe changes dynamically as the suspension works under the car.  Several factors are at work, and the effects combine to substantially change toe from the static settings.

Bump Steer:  this is the change in toe caused by loading or unloading the suspension.  Neons toe in slightly under compression, and toe out slightly under extension.  This is why a small amount of toe in is recommended above, so that the toe is near zero as the car is accelerating and weight is transferred to the rear.  Additionally, a small amount of toe in makes turn-in crisper as the outside front wheel is most heavily loaded during cornering, and the bump steer of compression helps this effect as well.

Ackerman Toe:  this design compensates for the tighter-radius path followed through a turn by the inside tire.  The steering geometry is engineered so that toe out increases as steering lock increases.  As the steering wheel is cranked, increasing toe out causes the inside tire to turn at a sharper angle, while reducing the steering angle of the outside tire.

Many autocrossers suggest toe *out*, but so far no one has met Erich's challenge in offering a scientific reason why.  Toe out runs contrary to the theoretical dynamics of the Neon's suspension.

3.6.19  Q: The Mopar Performance catalog lists a 19mm rear swaybar.  Does it *really* exist?
A:   Mopar Performance has a catalog entry for both 19mm (p/n P5007026) and 22mm (p/n P5007041) rear bars.    It's a mistake in the catalog; the 19mm rear bar does not exist.  For the first year or so, the 19mm bar was on 'national backorder'.  In actuality, this is the part number for the regular 16mm rear bar.  The 19mm bar was originally to be part of the ACR's trunk kit; however, the SCCA approved the 22mm bar and the smaller item was never produced.
3.6.20  Q: What is a 'trunk kit'?
A:   A trunk kit is a package of upgraded performance parts to be used in road racing.  At the time the Neon ACR was introduced, SCCA Showroom Stock club racing rules were very restrictive:  the cars were largely true to the name of the class, except for safety items like a roll cage.  Cars were required to be available for retail sale with the same engine, transmission, and suspension as the race version.  The ACR, Nissan's Sentra SE-R, and the Miata R are examples of "by the book" Showroom Stock entries.

However, in response to the ACR's dominance in Showroom Stock C, and very strong showing in SSB, the SCCA Competition Board gave in to pressure from manufacturers and drivers of other marques.  They allowed each car a pre-approved package of performance upgrades.  These are nicknamed 'trunk kits' because they come 'installed' in the car's trunk, to be fitted by the owner rather than the factory.

In theory, the Comp Board adjusts the content of each model's trunk kit to even the competition.  In practice, virtually everybody *except* the Neon racers got a big bag of goodies, and the ACR was rendered relatively non-competitive by the miniscule package that was approved by the SCCA.  Following Chrysler's withdrawal of contingency support for all SCCA-sanctioned events, the Competition Board appears to be adjusting the approved kits to some extent.

3.6.21  Q: Will wheels from any other Chrysler products fit the Neon?
A:   The forked 5-spoke alloys from the 2000 Neon ES match bolt pattern and offset and are a direct fit.  Also, the 16" split 5-spoke wheels from the Sebring convertible will fit the Neon if mounted with a 1/4" spacer to correct the offset.  However, wheels from the other Sebring/Avenger models will not since they are based on a different platform.  Below is some additional information on older Mopar products:
"All Chrysler built vehicles in the FWD era (starting in '78) have the same bolt pattern. The four lug wheels from a '78 Horizon will fit on a '94 Neon. (Although I don't see anyone trying this swap!)  The five lug pattern on the FWD cars up to '96 use the 5 x 100mm (4 inch) pattern.  Starting in '96, all the cars EXCEPT the Neon switched to the larger bolt pattern that I believe is 5 x 115mm. (4.5 inch).  So those huge 17" wheels on the new Caravan Sports that are larger versions of the Neon R/T wheels won't fit on the Neon, or other earlier K or L body vehicles.

Check out Shelby Wheel 101  for all you ever wanted to know about FWD Mopar wheels and then some.  Special thanks to Dempsey Bowling for his incredible FWD Mopar/Shelby Dodge website. It has pictures of all of them along with dimensions and other info about each wheel."

- John "Shelby Z" Fleck

3.6.22  Q: What is the difference between the black and the yellow Koni struts?
A:   About $800 a set.  The black Konis are the factory units, and no longer come slotted.  The yellow Konis are identical, slotted, and about 1/3 the price.  The yellow struts are, however, illegal for Showroom Stock club racing competition (they are legal in Stock autocross, though they may require a washer welded over the slots to remove adjustability).  Note that the legal black units are now available through Mopar Performance; they carry a different part number and are for some reason considerably less expensive.  Below are part numbers for each type (part numbers courtesy of Jim Waleke).
 
Item Part Number Price
OEM Koni strut (front, blk) 4656356 $460 ea.
OEM Koni strut (rear, blk) 4656196  $390 ea.
MP Koni strut (front, blk) P4876812 $225 ea.
MP Koni strut (rear, blk) P5007000  $245 ea.
Direct from Koni set (yellow) -- $575/set
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Neon Brake Information

4.1 Brake Systems

The Neon's brake system is well modulated; responsive but not touchy,  and evenly biased from front to rear for control.  All Neons have vacuum-assisted brakes, with or without ABS.  Most cars have front disc/rear drum, which is perfectly fine for all but roadracing use, where heat buildup is a concern.  Rear discs do brake somewhat better; however, they are about 16 pounds heavier.  Since the rear wheels only do about 20% of the braking, the performance difference between disc and drum is minimized.

The Neon's optional ABS is a three-channel system.  In fact, all street car ABS is three-channel, no matter what other manufacturers may say in their advertising.  All four wheels are monitored independently for lockup detection.  Braking effort is metered seperately to the front wheels, and the rear wheels are metered as a pair to promote stability.
 
Neon Brake Systems ('95-'97 m/y)
Designation BRC BRH BRA BRJ BRD BRF
Type Disc/drum Disc/drum, with ABS Disc/drum Disc/drum, with ABS Disc/disc Disc/disc, with ABS
Front Rotor OD 240mm 240mm 257mm 257mm 257mm 257mm
Front Caliper Piston diam. 54mm 54mm 54mm 54mm 54mm 54mm
Front Lining Abex 46Q3T Abex 46Q3T Abex 46Q3T* Abex 46Q3T Abex 46Q3T* Abex
46Q3T*
Rear Rotor or Drum OD 200mm 200mm 200mm 200mm 270mm 270mm
Rear Piston or Cyl. diam. 15.9mm 15.9mm 15.9mm 15.9mm 34mm 34mm
Rear Lining Bendix H3520A Bendix H3520A Bendix H3520A Bendix H3520A Bendix 7805 Bendix 7805
Master Cyl. bore 21mm 21mm 21mm 21mm 22.2mm 22.2mm
Proportioning Valve 400/.43
(black band)
400/.34
(gold band)
400/.43
(black band)
400/.34
(gold band)
400/.34
(gold band)
400/.34
(gold band)

*Notes for '98-'99 m/y:
BRA Front Lining changed to Bendix D7913.
All other Front Lining changed to BBA 2004.
BRD/BRF Rear Disc Lining changed to BBA 2006.
BRD/BRF proportioning changed.

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4.2 Brake System Questions and Answers:

4.2.1    Q: How have the brake options changed over the years?
A:    "Here's the deal with Neon brakes.  In 1995, there were *many* different brake systems available on Neons:

There was a 4-lug system (called 13" brakes, even though some cars with 14" wheels got them) that used 9.4" front discs and rear drums [BRC].  On Highlines, ABS was optional with these brakes [BRH].  This system [BRH] with ABS was standard on '95 Sport Sedans built before (approximately) August '94.  Do not be fooled by the 5 fake lugs on the 14" hubcaps... the early '94 calendar year Highline and Sport with 14" wheels had these 4-lug brakes!

There was also a 5-lug system (called 14" brakes, because they will not fit under wheels smaller than 14") that used 10.1" front discs with rear drums [BRA].  This system was optional on Highlines starting in August '94, had an additional ABS option [BRJ], and was the system that you got if you deleted ABS on a late-95 Sport Coupe or Sedan.  This system (without ABS) is standard on '96-98 Base, Highline, Sport and Expresso Neons [BRA].

We also have a 5-lug system that has 10.1" front discs with rear discs and ABS [BRF].  This system was standard on '95 Sports built after  (approximately) August '94.  It was possible in the '95 calendar year to delete the ABS (for credit) on a Sport, which then left you with the 14" disc/drum brakes [BRA].  This system [BRF] is what you get if you order the optional ABS on a '96-98 Neon.

Last but not least, there is the 10.1" front disc/rear disc without ABS [BRD].  In '95-97 model years, this system was used only on the ACR.  For the '98-'99 model year it is also standard on the R/T.

Beginning in the '96 model year, there are only three brake systems available: 14" disc/drum [BRA], 14" disc/disc [BRD], and 14" disc/disc with ABS [BRF]."

- Greg Smith

Editor's note:  I have gone through the post above and inserted the designations used in the Brake Systems table.  These appear in bracketed italics above.  Any errors in the designations are mine, not Greg's.
 

4.2.2    Q: Are the front disc systems all the same?
A:    "Yes, all of the 5-lug front brakes are the same.  The '98-'99 front calipers are supposedly a little bit stiffer than the '95-'97 ones.  You can identify them easily because they are painted/coated black as opposed to the silver color of the original ones.  The '98-'99 pads are different also (less tendency to squeal)."

- Greg Smith

4.2.3    Q: What kind of brake fluid should I use?
A:    "All DOT 3 and DOT 4 brake fluid is hydroscopic, meaning it absorbs water even from the air.  When brake fluid absorbs water, its boiling point drops which is very bad when the brakes are working hard.  It makes it easier to boil the fluid.  The main difference between DOT 3 and DOT 4 from what I can tell is the wet and dry boiling points.   Wet is when it is saturated with all the water it can absorb, and dry is when no water is in the fluid.  DOT 3 has a higher dry boiling point than DOT 4, but a lower wet boiling point.  I run DOT 3 and bleed often, to keep that boiling point as high as it can be.  If you were going to leave your brake fluid in for a significant period of time (like most people) DOT 4 would have a higher boiling point.  Fortunately the Neon has phenolic caliper pistons which insulate the fluid from the brake temperature much better than steel pistons.  I've never boiled the brake fluid in my race cars."

- Erich Heuschele

4.2.4    Q: Should I put on cross-drilled or slotted rotors?
A:    Why?  There is no performance advantage to be gained by installing either drilled or slotted rotors.  Drilled rotors have a tendency to warp, and the drilling creates stress points.  This can lead to cracks in a connect-the-dots pattern.  Slotted rotors are better, but still tend to warp.  Both types of rotor cause increased pad wear, as the small lip at each hole or slot erodes a bit of the pad material with each revolution.

Remember:  Porsche factory racing teams remove the stock drilled rotors and put on solid ones...

4.2.5    Q: Can I convert my rear drum brakes to discs?
A:    Yes.  But, as above, why?  Rear brakes handle about 20% of the braking load, which makes the conversion not worthwhile.  Grassroots Motorsports, in fact, converted their CSP autocross Neon ACR from discs to drums in back in order to save 16 precious pounds.
4.2.6    Q: What do stainless steel brake lines do?
A:    Braided, flexible stainless steel brake lines replace the rubber brake lines leading to each wheel cylinder.  Under heavy braking, hydraulic pressure inflates the rubber lines by a small amount.  Stainless steel lines eliminate this effect, which makes the pedal firmer and easier to modulate carefully.  Kits are available for the Neon, at around $75.
4.2.7    Q: Should I install high-performance brake pads?
A:    Performance-compound brake pads can increase braking power under heavy-use conditions.  However, their drawbacks can make them unsuited for street use:  they may operate worse than stock until well heated; they tend to squeal, dust, and wear out more quickly.  They can increase rotor wear as well.  In fact, many road racers use the stock pads except at high-braking tracks.


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