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I hear it all the time but what does offset mean?



Offset is the distance between the centerline of the wheel and the hub mounting surface. There are 3 different types of offsets: Zero, Positive and Negative. For our car (FWD cars) the offset is known as Positive. This is because the hub mounting surface is towards the front of the wheel and ahead of the centerline of the rim.




What offset do I need if I purchase aftermarket wheels for my SRT-4?

This is dependent on numerous variables such as wheel width, wheel diameter and tire size but generally speaking offsets in the range of 35mm to 45mm will work. An offset lower than 35mm will place the wheel out and past the fender and an offset higher than 45mm will place the wheel too far inwards making it come into contact with the brake calipers and/or suspension. Please note that the spoke design of a wheel plays an important role in determining fitment on higher offsets such as wheels with a 42mm or 45mm because they come into close contact with the front brake calipers. The rear brake calipers do not have this issue because of their smaller size and design. To avoid any clearance issues it is recommended that you find a wheel with an offset between 35-40mm. This is more or less just playing it safe so you don't buy a set of new wheels only to find out that they don't clear the front calipers. On that same note this does not imply that a wheel with a 42 or 45mm offset will not fit over the calipers. It will all depend on the spoke design of that particular wheel. There are plenty of wheels with a 42mm or 45mm offset that fit but there are also just as many that do not. It's always best to search the forums to see if another member has fitted a particular wheel of your interest.


Okay, I'm ready to buy some new wheels but how do I know which offset works with the wheel size I want?

As stated previously, there are many variables that come into play. Use the following as your guide for determining offset. This applies to 15, 16, 17, 18 and 19 inch wheels:



  • 7.0-7.5 inch wide wheels generally fit with offsets of 35-40mm.*see prior paragraph regarding exceptions noted in red*
  • 8.0 inch wide wheels will generally fit with offsets of 35-38mm with some wheels fitting with 40mm offset on coilovers. When going to a wider wheel the problem isn't so much clearance with the calipers but rather tire clearance with the stock struts and transmission case.
  • 8.5 inch wide wheels will require a 35mm offset on stock struts. On coilovers, 35-38mm.
  • 9.0 & up inch wide wheels are too wide for the car and have not been proven to fit.
What are hub rings and do I need them?

Hubcentric rings are designed to fill in the gap between the hub of the car and the center bore of the wheel. Most wheel manufacturers design their wheels with a center bore large enough to fit on most cars. The result is a small gap between the hub and the center bore. This gap usually doesn't allow for the wheel to fit hubcentric but rather lugcentric which sometimes can cause vibration. Therefore, to fill the gap and ensure the fitment is hubcentric, hub rings are used.

If you are going to purchase new wheels it's probably a good idea to purchase hub rings as well. This will ensure that the center bore of the wheel sits flush on the hub and will avoid any vibration that may occur while driving.

There are two kinds of hub rings that can be purchased: plastic and aluminum. Some say that excessive heat from braking can cause the plastic rings to melt and warp over time but for normal street use they don?t seem to be a problem. To determine which size hub rings you'll need for your aftermarket wheels, first find out from the manufacturer what the center bore diameter is. This number combined with the SRT-4 hub size of 57.10 will be the size you need for your hubcentric rings.

Example: 73.0 x 57.1

73.0 being the outter diameter of the hub ring (and fits inside of your aftermarket wheel) and 57.1 being the inner diameter (and fits over the hub on the car).

Metal hub rings can be purchased from Discount Tire Direct for about $15 shipped. All you need to do is just give them the size you need.

1-888-459-4081
Mike Ext. #304




What are spacers and do I need them for my wheels?


Wheel spacers are thin aluminum circular plates that go in between the wheel and the rotor. It works just as its name implies by adding space between the two. Spacers are ONLY used when the wheels offset is too high and the spokes come in contact with the brake calipers. Depending on how high the offset is will determine how thick of a spacer you'll need. Because every wheel design is different its hard to say when a spacer is needed. For example there are some wheels in a 40mm offset that will clear the calipers just fine while there are others that don't. Why? Its all because of the spoke design. As a rule of thumb, if your interested in a set of wheels that carry an offset of +45 or higher than chances are you'll need spacers. Be aware that it is recommended that you upgrade to longer wheel studs if a spacer bigger than 5mm is needed.


What if my ride is lowered on springs or on coilovers? Which sizes work without rubbing?

You can avoid any kind of rubbing by maintaining a proper ride height. If your car is dropped more than 2.0 inches than expect some rubbing on anything wider than the stock wheels. Hard cornering, passengers in the back seat and extreme bumps in the road can cause rubbing. There is no way around this. If you want those phat looking 8.5" wide wheels to go along with the massive drop on your coilovers than prepare for the fenders and tires to constantly be in contact. The good thing about coilovers is that you have the ability to adjust the height to give you the clearances needed. So please, don't ask if a certain wheel and tire will fit on your coilovers because common sense will tell you that if it doesn't you need to RAISE THE CAR! :readclose On lowering springs you don't have that luxury. Just be aware when you buy those mega drop lowering springs if you plan to buy wider wheels in the future.

17x8 wheels (35 offset) with tire widths 235 and UP are more prone to rubbing on lowering springs. Why? Because usually the spring rates are too soft and there is too much compression/rebound when driving over bumpy road surfaces.

Follow the fitment guide provided in this sticky thread and you should not have issues with rubbing UNLESS your car is too low as stated above. Other things that may exhibit rubbing might be a tire too tall (taller than 25.4") or a wheel offset that is too low (less than 35mm). If you follow the fitment guide you should be ok.


Can I fit any 5 lug wheel on my car?

NO. The wheel must have a bolt pattern of 5x100 (and the correct offset of course). If the wheel is drilled for multiple 5 lug bolt patterns and includes 5x100 then yes it will fit. If the wheel is only drilled for one bolt pattern, lets say for example a 5x114.3, then NO it will not fit. You need a 5x100 bolt pattern. There are wheel adapters on the market that will allow you to change the 5x100 bolt pattern to any lug pattern you want but this is an extreme route to go with to fit a set of wheels as you will have to compensate for the extra width of the adapter with a low offset wheel.

Are there other cars that have the same bolt pattern as ours?

Yes. Below is a list of recent cars that have the same bolt pattern.

list provided by Stowaway

Audi TT (99-up)
Buick Century (80-89)
Buick Skylark (81-97)
Buick Skyhawk (81-89)
Cadillac Cimmaron (81-88)
Chevrolet Beretta (87-up)
Chevrolet Cavalier (all)
Chevrolet Celebrity (80-89)
Chevrolet Citation (80-86)
Chevrolet Corisca (87-up)
Dodge Aries (86-89)
Dodge Daytona (85-93)
Dodge Dynasty (88-93)
Dodge Lancer (85-89)
Dodge Neon (97-up)
Dodge Neon (94-96 5 lug models)
Dodge Shadow (87-94)
Dodge Spirit (89-95)
Dodge Stratus Sedan (95-up)
Lexus ES 250 (90-91)
Oldsmobile Achieva (92-up)
Oldsmobile Ciera/Cutlass/Calias, non HD/cruiser model (82-91)
Oldsmobile Firenza (82-88)
Oldsmobile Omega (80-85)
Plymouth Acclaim (89-95)
Plymouth Breeze (96-up)
Plymouth Caravelle (85-89)
Plymouth Neon (96-up)
Plymouth Reliant (86-89)
Plymouth Sundance (84-94)
Plymouth Voyager (86-96)
Pontiac Fiero (84-88)
Pontiac Grand Am (85-98)
Pontiac Grand Prix (99-up)
Pontiac J-2000 (82-84)
Pontiac Phoenix, if came w/ factory 14s (83-84)
Pontiac Sunbird (85-94)
Pontiac Sunfire (95-up)
Pontiac 6000, some cars (82-89)
Pontiac Vibe (03-up)
Toyota Camry (83-91)
Toyota Celica (86-up)
Toyota Matrix (03-up)
Subaru Impreza, WRX (non-STi) (93-up)
Subaru Impreza WRX STi (04)
Subaru Legacy (95-up)
Volkswagen New Beetle (98-up)
Volkswagen Corrado V6 (93-94)
Volkswagen Golf V6 (93-98)
Volkswagen Golf (99-up)
Volkswagen Jetta V6 (93-98)
Volkswagen Jetta (99-up)
Volkswagen Passat V6 (92-97)


Do I need new lugs if I buy aftermarket wheels?

In most cases, YES. The reason for this is that most aftermarket wheels have very small and tight lug holes and the large bulky stock lugs will not fit. You'll most likely need to pick up "tuner" lugs. These tuner lugs have slimmer bodies and will fit inside the lug holes of your aftermarket wheels. The design for most of the tuner lugs are spline drive which refers to the seating area of the lug nut.

Always check with the wheel manufactuer to see if it requires a special lug other than the spline lugs. You can purchase tuner lugs on ebay or any aftermarket wheel shop.

The lug nut size (or thread pitch) for our cars is 12 x 1.50.



I have a SRT-4 ACR, what wheels will fit my car?

Any wheel that fits the base SRT-4 will fit the ACR. The tire size is what determines fitment on the ACR since the spring perches are lower. (scroll below for ACR tire explanation)







I want to fit the widest tires I can on my stock wheels, what size should I go with?

The stock wheels are only 6 inches wide and can only accommodate tires with certain widths appropriately for the best performance, fitment and safety. A 215/50-17 is about as wide as you can go on the stock wheel. Why? Because anything wider will cause some issues. First is safety. A tire too wide will cause overlapping of the sidewalls which will flex too much under hard cornering or any extreme driving behavior and may cause the tire to blow out due to puncturing of the sidewall on the edge/lip of the wheel. Second is performance. You will actually lose performance due to the improper fitment. You will not be utilizing the full contact patch which negates the whole purpose of going wider to begin with. Not to mention handling is affected as well. You must follow the tire manufacturer's recommendations for wheel width. You will not find one that allows a 6 inch wheel to be installed on anything wider than a 215.

There are many SRT owners that have installed 225/45-17?s on the stock wheel and claim to have no issues. Although they physically fit on the wheel, the points mentioned previously is why going with this size or wider is not recommended. Buy at your own risk.

If you decide to opt for a 215/50 be sure to pay attention to the overall diameter of the particular brand tire to stay within OEM specs. Some brand/model tires are larger than others.


Why is it important to buy tires that have the same overall diameter as the stock tires?

The first important factor for this is fitment. If you purchase a tire that is too tall, it will come into contact with the spring perch on the stock strut and will cause rubbing and in some cases the wheel may not even bolt up all the way because the tire won't clear the strut. Secondly is speedometer accuracy. A tire too short or tall will cause your speedometer to give incorrect speeds. In general a 3% + or - change in diameter size compared to stock is acceptable however on our stock struts I would not exceed 2%.

Follow this LINK for an easy to use tire dimension calculator.


I just bought aftermarket wheels, what size tire should I go with?

The following are the most common and popular upgrade tire sizes:

15" wheels = 215/60-15
16" wheels = 225/50-16
17" wheels = 225/45-17
18" wheels = 225/40-18
19" wheels = 225/35-19

These tires are all closest to the overall diameter of the stock tire size and do not interfere with suspension pieces, fenders or any of the above (as long as both the offset of the wheel and the proper ride height is correct). There are other sizes that can be used but they will either be slightly smaller or larger in overall diameter.


What size wheels can I fit my stock tires on?

Your 205/50/17 Michelin Pilot Sport or BFG KDW 2 tires can fit on any 17" wheel up to 7.5" wide. That is the limit that the tire manufactuer recommends. Any wheel wider than 7.5" requires a wider tire.

What are the widest tires I can use without any rubbing?

This is one of the most common questions asked. In the quest for more traction everyone wants to throw on the widest tires possible but there is a sad reality to all of this: we drive economy cars. Our little Dodge Neons were never designed to house wide wheels and tires. There is only so much room in the wheel well to accommodate a wide wheel and tire before clearances with the suspension and fender become an issue. You certainly wouldn?t want to ride around with your tires sticking out past your fenders a few inches would you? Not quite practical for daily use.

So how wide can you go? Follow this guide for selecting tires wider than what was suggested on the previous base guide. These are sizes that are matched with the appropriate wheel width as recommended by most if not all tire manufacturers and all are relatively close to the stock tire diameter needed to maintain speedometer accuracy and gearing. Mounting a tire that is too wide for a particular size wheel will result in sub par performance and safety issues.

17x7.0 (offset must be 35-45mm) = 225/45-17

17x7.5 (offset must be 35-40mm) = 225/45-17

17x8.0 (offset must be 35mm) = 245/40-17

18x7.0 (offset must be 35-45mm) = 225/40-18

18x7.5 (offset must be 35-40mm) = 225/40-18

18x8.0 (offset must be 35mm) = 245/35-18 or 235/40-18

18x8.5 (offset must be 35mm) = 225/40-18

If you feel bold enough to step outside of this guide and try other sizes feel free to do so. However keep in mind of clearances mentioned previously and maintaining a tire diameter closest to stock. It is also important to note that no one to my knowledge has been able to mount a tire WIDER than 245 on the srt-4 without running into clearance issues. *this is excluding race prepped srt-4?s which are heavily modified to accommodate wide tires and would not apply to your average daily driven vehicle.*

I already have tires but want new wheels, can I use these tires on the new wheels?

Here are the safe and recommended rim widths for common tire sizes for the SRT-4. You still need to follow the rim fitment guide concerning wheel offset even when using a less than maximum width tire.

205/55-16 - 5.5"-7.5"
225/50-16 - 6"-8"
205/50-17 - 5.5"-7.5"
215/50-17 - 6"-8"
225/45-17 - 7"-8.5"
235/45-17 - 7.5"-9"
245/40-17 - 8"-9.5"
225/40-18 - 7.5"-9"
235/40-18 - 8"-9.5"
245/35-18 - 8"-9.5"
225/35-19 - 7.5"-9"
235/35-19 - 8"-9.5"


I have a SRT-4 ACR, what tires will fit my car?

On the ACR the spring perches on the Tokico struts sit lower than the base SRT-4 so tire options will differ between the two vehicles. Why? Since the spring perches on the ACR sit lower they don't allow enough room for taller tires that normally would clear the base SRT-4 struts. Because of this you will need to find a tire that is 23.7" in diameter or shorter and although there are some that fit the bill, there's just one problem -- none of them meet the load capacity requirement. The ACR is cursed from fitting anything other than what comes right from the factory which is the 225/45-16. Want a wider tire? Not happening without sacrificing safety. You could always change out the struts to the base SRT-4 struts or coilovers which would allow you plenty of tire/wheel upgrades but you'll have to ask yourself an important question, why did you buy a ACR in the first place?
 

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Discussion Starter · #2 · (Edited)
Check out the new revised and updated Wheel & Tire Tech thread! :) I've tried to put it in an easy to use format that everyone can understand. I've also tried to cover most of the common topics. This thread is always a work in progress and as new topics or issues that become a common reoccurrence in the Wheel Forum come about, I'll address them in this thread.

**DO NOT message me until you have read this thread carefully.** Most of your questions are answered here but if you still need clarification I would be glad to help.
 
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