EliteCM.net

ULTIMATE WHEEL AND TIRE CALCULATOR (http://www.rims-n-tires.com/rt_specs.jsp)

i understand Tims problem with ppl asking not the same but similar questions over and over again.

if you have questions then ask here (http://gen7accord.net/forums/viewtopic.php?t=4187)

just found this neat calculator
use this and read what it says, then go outside and measure what calculator told you

WHEEL OFFSET CALCULATOR (http://www.1010tires.com/WheelOffsetCalculator.asp)

Tire size calculator if you going with new wheels and tires, check how much bigger wheels gona be and effect of that on speedometer reading

TIRE SIZE CALCULATOR (http://www.miata.net/garage/tirecalc.html)


PLEASE NO MORE QUESTIONS LIKE THIS, this is as simple as anybody can explain and show you

Tim or other mods can delete this if they want to


(http://www.rx7.org/Robinette/images/wheel_offset.gif)
(http://www.tirerack.com/images/wheels/tech/offset.gif)


Wheel Offset: Why It Matters (http://www.hondatuningmagazine.com/tech/htup_0807_honda_wheel_offset_guide_faq_tips_biggest_lip_wheel/index.html)
Look Cool Without Being A Dummy
By John McNulty


(http://image.hondatuningmagazine.com/f/10242957/htup_0807_01_z+wide_offset_fender_flares_falken_azenis.jpg)
If there's one thing hard parkers and road racers can agree upon it's that wheels and fenders should fit flush with one another. Perhaps it's because of how good it looks when the wheels and body surface are in the same plane. Or maybe it's because cars tend to handle better with the wheels positioned farther out. Either way, since wheels travel upward as suspensions compress, the farthest outboard they can go is just about flush with the fender. If the car looks and handles better, then despite what we've been told, maybe we can have our cake and eat it too.

(http://image.hondatuningmagazine.com/f/10242963/htup_0807_02_z+wheel_offset_diagram_centerline_rear_spacing_negative_positive_offset.jpg)

Offset: What the heck is it?
All of this brings us to wheel offset, which is simply the distance between the wheel's hub-mounting surface and its center plane. Positive offset means the hub-mounting surface is closer to the wheel's outboard side. Conversely, negative offset means it's closer to the inboard side. If the mounting surface coincides with the wheel's center plane then offset measures in at zero. In other words, offset determines the lateral, or side to side, position of the wheel. As wheel widths change, the offset combined with the new width must be chosen properly so that the wheel and tire have enough space within the wheel well to avoid rubbing or unwanted contact with other components.

(http://image.hondatuningmagazine.com/f/10243029/htup_0807_03_z+wilwood_brake_calipers_cross_drilled_slotted_rotors.jpg)
Front-wheel-drive cars are generally equipped with positive offset wheels. Most manufacturers design cars with a negative scrub radius up front that is made possible by positive offsets. The scrub radius simply refers to the distance between the point where the steering axis intersects the pavement and the center of the tire's contact patch. Since the scrub radius has to do with steering geometry, such positive offset requirements only apply up front. However, since factories typically prefer using similar wheels all around to reduce manufacturing costs, the rear wheels typically get the same positive offset wheels as the front. If we're talking about rear-wheel-drive cars, then most OEMs incorporate a minimal scrub radius up front.

Why should you Care?
The ability to understand wheel offset can help solve a variety of wheel fitment issues. Wheel and tire upsizing often requires altered offsets. The wheel supplier will usually have the information necessary in terms of which offsets will and will not work, and, if that doesn't work, there's probably at least one thread somewhere on the Web with at least one guy who's tried the same wheel combo you're considering, but don't count on it. Sometimes the info just isn't there and the only way to know for sure is to measure and calculate. It all begins with your stock wheels and tires.

The minimum clearances on both sides of the OEM wheel/tire package must be accounted for prior to assuming a potential maximum tire width-this includes the space between the nearest suspension component as well as the fender. Keep in mind that oftentimes when dealing with extreme steering positions, minimal, inner wheel well tire rubbing might occur. Also, some tires measure differently than others. For example, some 225mm-wide tires measure similar to some that are labeled as much as 245mm. It's best to allow an 1/8-inch of play for potentially wider tires.

(http://image.hondatuningmagazine.com/f/10243044/htup_0807_08_z+honda_front_suspension_diagram.jpg)
More about offset
With clearances measured, you're almost ready to look really smart in front of your friends. First: A wider tire on a similarly offset wheel reduces the gap the same amount on both sides but adding 1mm of offset moves the wheel away from the fender-closer to the inner wheelwell-by 1mm. Usually, the inner and outer gaps will be different and this is why new wheels require different offsets. To center the tire so that the inner and outer gaps are equal, take the distance of the outer gap, subtract the inner gap from that figure, and divide this number by two. Add this figure to the old wheel's offset, this gives you the new wheel's offset. For example, imagine a stock 195mm tire and a new 225mm one. Picture inner and outer gaps, 30mm and 21mm, respectively. Give the old wheel a 45mm offset but first be sure the new tire will fit. Since the total gap in this example is 51mm (30mm plus 21mm), and the tire width increased by 30mm, then there is 21mm left over. Even after assuming that the new tire might be an extra 1/4-inch (6.4mm) wider than expected, there's still more than 14mm clearance. In short, 225mm will work. Subtract the inner gap from the outer gap, which is -9mm (21mm minus 30mm), to obtain the new wheel's offset. Take half of this number (-4.5mm or simply round to -5mm), add this figure to the old offset, which was 45mm to net your 40mm offset. A quick check of Volk TE37 and CE28 wheel offsets reveals a +35mm and +42mm offset available in 15x7, both of which will work just fine.

On a related note, you also need to know about backspacing. Specifically, it's the distance between the wheel's inboard outer edge and its hub-mounting surface. Proper backspacing calculations ensure against any unwanted clearance issues between tires and suspension members, especially when larger wheels and tires are used. Enough said.

Measuring Backspacing And Calculating Offset
All you need to properly measure offset is a tape measure and a straight edge. We're measuring the wheel's backspacing here, which is needed to calculate its offset.

(http://image.hondatuningmagazine.com/f/10243053/htup_0807_05_z+measuring_backspacing_and_calculating_offset.jpg)
How to measure it
Offset can be measured with or without the tire installed. When measuring with the tire, offset can still be measured without deflating it, however, it might be more accurate to measure offset on a bare wheel but that doesn't mean you can't get within a millimeter or two of the true figure with tires in place. After all, as long as offset is measured within a 2mm tolerance, things should be fine. Should you go the tire-installed route, it's easiest to measure the overall tire width using a straightedge placed across the tire to a level spot on the ground. Next, measure from the same straightedge location to the wheel's mounting surface. The only tools required to measure offset are a long straightedge, a tape measure, and this simple mathematical formula:

Offset equals 0.5 (tire or wheel width) minus the distance from the mounting surface to the tire or rim edge.

Offset and track widths
Altering offsets also changes track widths. Reduced offsets result in larger track widths. This can improve cornering speeds by reducing lateral load transfer from the inside tires to the outside tires. By keeping the tire loads uniform, tires can generate increased lateral grip. This is why most race car tires are as far outboard as possible. On the other hand, changing the wheel width does not change the track.

Another way to increase track without having to purchase new wheels is to install wheel spacers. Spacers are available in different thicknesses, from about 5mm to 30mm or more, depending on the application. Eibach manufactures one of the nicest sets of spacers on the market. Their spacers are precision machined with tight tolerances, which helps ensure that wheels stay securely attached to their hubs. Eibach manufactures 5mm non-hub centric and 15mm hub centric options, each with longer wheel studs.
Determining the proper offset when upsizing wheels and tires can be challenging. It's difficult to determine how far the tire will extend over the wheel lip for a particular tire and rim combination. Therefore, it's difficult to know beforehand whether the tire will rub on the suspension or the fender. Even with a small tire width change on the same wheel it's possible to estimate how much wider the new tire will be. For example, West Coast Honda Challenge H4 multiple champion Edik Stepanyan somehow shoehorned a Toyo 245/45-16 RA-1 onto a rules-specified, 7-inch-wide wheel and then fitted four of them onto his '93 Integra race car. He used 225/45-15 sized tires previously and with careful clearance measurements on both sides of the tire he determined that the 245's extra width would fit using wheels with a more common offset, and this was on a car that came from the factory with 195/60-14s on 51/2-inch rims. Needless to say, the gaps on both sides of the tire are minimal.


Wide Offset Fender Flared Ep3 Civic Deep Dish Wheels
Don't get us wrong, the low offsets look cool, like on this EP3 Civic, but don't expect your front-wheel drive to handle as well as it did if you were to stick with something closer to what Honda intended.

The scrub radius
Altering wheel offsets also affects the scrub radius. Recall that the scrub radius is the ground-level measurement between the kingpin inclination axis (KIA) and the tire contact patch's center. For double-wishbone suspensions, like most pre-'01 Hondas, the KIA is the angle between a vertical axis and the imaginary line through the top and bottom ball joints' centers when viewed from the front of the car. For a strut-based car, the imaginary axis travels from the top bearing mount's center to the lower ball joint's center. If the KIA intercepts the ground outboard of the tire contact patch's center, then the scrub radius is negative. On the other hand, if the KIA intercepts the ground inboard of the tire contact patch's center, then the scrub radius is positive. Front-wheel-drive cars, including Hondas, are usually set up with a negative scrub radius.

A negative scrub radius is preferred for front-wheel-drive cars since it gives a stabilizing effect when traction between the left and right wheels varies. If a single front wheel loses traction during acceleration or braking-like what would occur if one tire goes over a patch of ice-the other front wheel will toe-out a certain degree depending on the amount of steering compliance, which will tend to steer the car in a straight line. At the same time, the driver will feel a certain amount of kickback through the steering wheel.

Although not related directly to wheel offset, another dangerous trend adopted from the drifting world is tire stretching. Undersized, stretched tires make for great slides on the track but a dangerous ride on the street. Do this one at your own risk.

Spacing wheels out by means of smaller offsets or spacers increases the scrub radius. This makes a negative scrub radius less negative, maybe even positive. This could lead to unequal front-wheel traction depending upon the difference between the old and new offsets.

Offset also affects suspension stiffness through the suspension's motion ratio. With less offset, the wheel's leverage about the inboard lower control arm pivot increases while the suspension spring leverage remains constant. The net effect is a reduction in the effective wheel spring rate. For example, a stock DC2 Integra fitted with wheels with 10mm less offset will have a 5 percent lower wheel rate. Therefore, to recover the lost suspension stiffness, a 5 percent stiffer spring is needed.

Offset and its effects
Production cars are built with wheel offsets that minimize wheel-bearing load. In corners, excessive lateral tire loads add stress to wheel bearings. Altering offsets affect how much load each of the two wheel bearings see both in straight-line driving and during cornering. Production-based race cars like the CRX and Integra that run stickier tires and less positive offset, exhibit somewhat high-bearing loads. Thankfully, Honda wheel bearings are strong and few problems occur.

(http://image.hondatuningmagazine.com/f/10243086/htup_0807_06_z+broken_civic_knuckle.jpg)
Broken Civic Knuckle
Improper wheel offsets can lead to a variety of problems ranging from poor handling characteristics to broken suspension components, like this Civic knuckle.

Even suspension knuckles aren't immune from offset changes. Longtime Honda racer Sam Rothschild has suffered two complete knuckle failures on his CRX. Of course, he runs +35 offset wheels with sticky Toyo 225/50-15 RA-1 tires and a stiff suspension. The added leverage created by this offset causes a much larger bending moment in the knuckle, which over time led to a fatigue fracture on two different knuckles, but this is for a highly stressed race car and is a rather unlikely scenario when concerning the typical Honda street car. Regardless though, offset does do more than just fill or not fill the fenders-it affects handling, steering, traction, even the service life of otherwise unbreakable suspension components like knuckle assemblies. That should be more than enough reason for you to rethink that sick, fat lip, rear-wheel-drive-looking offset next time you go shopping for new shoes.

Information was transfered from Gen7Accord.com.

Very insightful offset thread. You are the number one sticky thread creator Thien!

Ehm, since the Wheel Q&A is no longer available on Gen7 mind if I ask here?


I'm looking at some Volk Racing GT-V rims

The specs are 19x8 with a 49mm offset.  

I'm pretty sure they will work without issues but the offset is pretty tame and I might have to run some spacers to get a more aggressive fitment.  Thoughts?

It's a good thing you asked in here Milan.  When it comes to the set up you're mentioning, I would suggest trying them without spacers.  If you have any backspacing clearance issues, then I would use a spacer.  Conservatively speaking, you shouldn't have any issues running those wheels without modifications.

This is very good info. I hope to be using it soon.

I agree with Tim on that Milan. You shouldn't run into any problems with a 19x8 +49 offset.

OK, I have a question, I am thinking about going with a set of Rota "battle" wheels they are 17x7.5 with a +45 offset. I think that offset will work but I would greatly appreciate your answer. If it helps, When i get my bike sold i plan to order a super-cup kit.

+45 will work just fine, but please do not get Rotas.

(http://i35.photobucket.com/albums/d199/7thGenVillian/rotas-suck.jpg)

Why do rotas have such a bad rep? I have no experience with them.

They are cheap knock offs of the higher brand name wheels. They have a bad rep of being weak, bending easily, and or breaking.

oh well thanks for the info..

+1 on the Rotas.  Stay away from those.  They're known for cracking under normal driving conditions.

As far as the size goes, 17x7.5 +45 will fit.  For future reference, it helps if you mention if you have a coupe or sedan.  You can run lower offsets on coupes.

Thanks for the tip Tim. How happy are you with your buddy club wheels?

I'm quite happy with my wheels.  I've smacked a few pot holes on accident and they've held up just fine.

Good, the roads here in chattavegas suck pretty bad yet we are ranked for having some of the best roads in the country... dont really know how that works.

Sorry for the threadjack

like the wheel and tire size calculator. how do you determine the widest tire size based on wheel dimensions?

ex. what is the widest tire you can fit on an 18 x 7.5, +45 offset wheel?

i found a set of gram lights and caleb(o4coupe) said he fit them on his car one day but i would like yalls opinion. The guy who has them says they are a +20 offset is that right, and would they work?

They wouldn't.  Just because they are Gram Lights doesn't mean they will fit.  You need to make sure that they are the correct size.  A +20 offset will not fit our cars unless it's like a 4" wide wheel.  Please read the OP of this thread.  It's intended purpose was to help you understand how to figure out what wheels will fit.  You obviously didn't read the OP if you're asking questions like that.  I know it's a lot of information, but it's GOOD information if you don't understand wheel and tire sizes.

wowo really nice calculators !! A++

How about one that does both simultaneously Thien?

I love this site: http://www.rims-n-tires.com/rt_specs.jsp (http://www.rims-n-tires.com/rt_specs.jsp)

Credit goes to Chris (MTSixSpeed) for the link before I bought my weapons. Feel free to put this in your OP.

-JT

OP updated with the link at the very top.

this thread is awesome!

rims-n-tires website has a really good calculator not only for offset  but also for tires

gives a visual feel for the difference between rims

This is a pretty good tool to use too.

http://marksink.com/tire_wheel_offset/offset.html (http://marksink.com/tire_wheel_offset/offset.html" onclick="window.open(this.href);return false;)

Im thinking of going with a new set of shoez

7.5
5X114.3
42mm offset
on 225/40/18 tires

I'm pretty sure i'll be ok but any thoughts are well appreciated! What is the typical range of offset we can run without any problems... 38-45?

...I can't remember what my offset is now that I am running...

Those offsets will be fine

Offset is dependent on the width of the wheel Billy.  The wheels will be fine because that is the same size as my summer wheel set up.  The tires are a bit skinny for my taste, but you should be fine with 225's.  I have 245's on my wheels right now.

Kool, I bought the rims this morning lolz, couldn't pass up on the price. Maybe I will run 235 tires... we will see!

If you have the opportunity, run 235's.  If you want to be a baller like me, run 245's.

Well I would have to see your tires up close again to see if I would run 245. Im running 225 now so 235 would def be off the skinny side... I have plenty of time before I get some rubber. Thanks for the input Tim  

not having much luck with the calcultor so i will ask anyways, im looking at a set of 17x7 and need to know what tire size would be best. any suggestions?

The calculator works fine for me.  Strange?!?!

Considering you're looking for something close to the 205/60/16 that your car came with, and you are getting such skinny wheels, I'd suggest 215/50/17's or 225/50/17's.  What wheels are they anyway?

im lookin at a few different and havent narrowed it down to one yet, and as far as the tire size i was thinking that a 225/45 would keep me closest to the oem rolling diameter

225/50 should be closer

k, thanks.

I want to order these rims but i dont know if they will fit my rear
they are 17X9 35 offset and i am slammed all around.

my fenders are not rolled yet.

Tires i want streetched tires!!

Sure man.  Go for it.

Stretched tires are unsafe man! Don't fall into this trend.

that depends how much you stretch.  a slight stretch, given that the tire width still falls within the acceptable range for the width of the wheel, can heed better performance.  i.e. a 255 on a 9.5" wheel.

now if you're planning to stretch a 205 on a 9", then that's just stupid and unsafe.

as for the 17x9 +35 fitment, you'll need to roll fenders and run some negative camber.  depending on your tire size, will decide how much camber you need to run and how much you need to roll you fenders.

They'll be hellaflush approved.

actually, they probably won't be.. they'll sit flush, but they won't be hellaflush..

and if he stays with his current ride height (the ride height he has in the pictures on his profile), he won't be low enough to be considered hellaflush..

Those hellaflush guys are dicks.

I'll probably never fully understand when it comes to these things lolz...

Will this work on my ride... I know the normal offset should be +38^ but how will the below affect me on a daily basis?

Size: 2 Front Rims are 18X8.75 with +20 offset

Size: 2 Rear Rims are 18x9.75 with +20 offset

I've never been a fan of wider wheels on the rear of a fwd car.  Just my $.02.

I told the same thing to Pete.  I miss that dude.

Billy, you'll be mexiflush with that kind of offset.  Nelson, you're drunk again aren't you?

billy those will need some work to pull them off but it has been done plenty of times.. those xxr wheels your talking about actually have a +22 offset not 20. also you should look into doing a square setup like 9.75 all around. i pulled the trigger on a set of these wheels so ill let you know how they work out for me.. i know not many here like the look but fucvk it.. also my fenders are getting some work at the body shop to be able to run that setup with less camber

Okay Mexiflush sounds good to me Tim but I definetly dont want em' poking out to much... Lolz

*Edit: I just typed in Mexiflush in a google search and I'm not to fond of the idea, I guess I will see what Alex will do and see how his ride looks since we basically have the same car and color. Cuz the few 7th genz that popped up were not looking to good to me!

Thanks, Alex... I've been wanted to change the look alittle of my ride, kind of getting bored of it, lol. Do you think 8.5 all around would be better so I wo'nt have to roll fenders. I probably will have to alittle I bet even though. What tire size would you prefer.....?

Alex how the heck did you know It was for the XXR wheels... damn you reading my mind  :flip:

Saw this setup as well... what tire size would you prefer.....?

Specifications   
Wheel Diameter 18"
Wheel Width 9.5"
Bolt Pattern 5-100/5-114.3
Offset +38mm
Backspacing 6.75"
Centerbore 73.1mm
Approx. Weight 24.7 lbs

The problem is that your wheels are going to stick out pretty far if they're that wide with such a low offset.  I have 18"x7.5" +42 wheels right now with a 15mm spacer, which makes it a 27mm offset.  Those fucking things stick out like crazy in the front.  Is there a reason why you want such wide wheels Billy?

Here's a pic of my wheels with the spacers on the front.  My fenders are rolled and pulled, the wheels have about -.5º to -1º of camber in these pics and they still stick out past the fenders.  Now, imagine a wheel that's 2" wider, which will stick out another inch plus the 7mm.  They're going to be fucking mexi flush, and that's no bueno if you're Puerto Rican.
(http://i58.photobucket.com/albums/g274/timot_one/Accord%20Pics/Wheels/DSC_0047.jpg)
(http://i58.photobucket.com/albums/g274/timot_one/Accord%20Pics/Wheels/DSC_0048.jpg)
(http://i58.photobucket.com/albums/g274/timot_one/Accord%20Pics/Wheels/DSC_0050.jpg)
(http://i58.photobucket.com/albums/g274/timot_one/Accord%20Pics/Wheels/DSC_0051.jpg)
(http://i58.photobucket.com/albums/g274/timot_one/Accord%20Pics/Wheels/DSC_0052.jpg)

FYI, Tim is also running a 245 on a 7.5" rim, which isn't a square setup and is why you see some tire bulge around his wheel..  You can get away with wider wheels if you are willing to run negative camber, tire stretch, and pull your fenders.

The specs you posted, 18x9.5 +38, will stick out another 16mm than Tim's setup.  On a 9.5" wheel, I would go with a 255.  You can squarely fit a 265 on a 9.5" rim, but if you're planning to run that aggressive of a wheel, I would looking into a 235 to 255 width tire.

How low are you planning to go?

I think I want it a littleless than what you have Tim, plus I like how mine sits right now it's just the rims I want offer the odd offsets for an aggressive look. I'm running a 225/40 tire right now with plans to go 225/45 for a tad bit more meat since the NYC streets don't seem to be getting  any better. I don't mind running a 18 X7.5 rim since thats what im on now. I was just curious of the fitment on the other specs mentioned.

Tim why are you running the 15mm spacers... if you didn't wouldn't your wheels fit more flush and not stick out as much? I thought that if I did the 8.5 wide rimeit would fit closely to what it looks like on your ride now.

I'm trying to get the specs of my boys ride which has the setup  I want but the bastard hasn't replied to me yet lolz...

I believe Tim needs the spacers for his huge ass RL calipers. Lol

:lamp:

That makes sense :exclaim:

So still havent gotten the specs from my boy but here is how the wheels look on his ride. I'm not going for that look in the rear cuz im not as slammed as him but this way we have a better visual of the look I want.

(http://i24.photobucket.com/albums/c14/crazycreashunz/Misc%20Gen7z/1-1.jpg)
(http://i24.photobucket.com/albums/c14/crazycreashunz/Misc%20Gen7z/2-1.jpg)

Here's another ride with the same setup:

(http://i24.photobucket.com/albums/c14/crazycreashunz/Misc%20Gen7z/3-2.jpg)

What handling advantage does the Hella Fail look offer?

None.

Actually, having that much camber makes your car handle worse.  I remember when I installed my front camber kit, and set the front camber all the way in with as much negative camber just to drive it to the shop for an alignment.  When I drove it to the shop, it was horrible to drive.  My car was so twitchy that it was dangerous to drive.  On top of that, you'll destroy your tires in a few thousand miles.  IMHO, it's a "look" that will cost you money and put you and everyone else on the road in danger.  Maybe if you have a trailer queen, it's okay.

Great thread guys

right now i'm running 18x8" with 32mm offset and 225/45 18 tires    with no issues
i'm considering 18x9" with 50mm offset and 245/40 tires
would that be okay?

BTW I have a 2007 sedan with rolled fenders