Dan Martin

Since we have so many questions about fitment of various wheels and tire combinations, I figured we should have a good resource for us to compile our knowledge of what fits and what doesn't. We started a similar thread in August '03 but a lot has change since then and I think it's easier to redo the list instead of trying to rework the old one.

First of all, let's cover the OEM equipment specs:
Tires: 215/50-17
Wheels: 17x7, +55mm offset, 5x114.3mm (5x4.5") bolt pattern, 64.1mm centerbore
Wheel bolt torque (just some bonus info ): 11 kg-m or 79.6 lb-ft (although I'm sure 80 lb-ft should be ok )

Wheel Size:
Members have been able to mount anything from 16" up to 20" on the TSX. So long as the outside diameter of the tire doesn't change, you will be fine with any size in that range. Wheel widths can range from 6.5" for winter tires up to 8" for summer. Some people have fitted larger wheel widths but selecting a tire and offset that fits is difficult. I'll let other members post the particulars of their setup if it they have a solution that works.


Offset:
Higher offset means the wheel sits further into the wheel well. Lower offset means it is pushed out towards the outside of the car.

In general terms, the higher the offset, the better. The TSX seems to have all kinds of space on the inside of the wheel well.

The only problem with high offset wheels is trying to find them. Few manufacturers make an offset >50mm.

Ideally, keep the offset higher than 42mm and you'll be ok. Several members are running 8" wide wheels with 235mm wide tires at 42mm offset and don't have any trouble with rubbing, even when lowered.


Tire Size:
Here is a good assortment of tire sizes for everything from 16" winter wheels to 20":
Specification ..Sidewall ..Radius ..Diameter ..Circumference ..Revs/Mile ..Difference
215/50-17 .....4.2in .......12.7in ....25.5in ......80.0in ..............792 ..........0.0% **OEM**
205/60-16 .....4.8in .......12.8in ....25.7in ......80.7in ..............785 ..........0.9%
215/60-16 .....5.1in .......13.1in ....26.2in ......82.2in ..............771 ..........2.7%
225/50-16 .....4.4in .......12.4in ....24.9in ......78.1in ..............811 ..........-2.4%
205/50-17 .....4.0in .......12.5in ....25.1in ......78.8in ..............804 ..........-1.5%
215/45-17 .....3.8in .......12.3in ....24.6in ......77.3in ..............819 ..........-3.3%
225/45-17 .....4.0in .......12.5in ....25.0in ......78.5in ..............808 ..........-1.9%
225/50-17 .....4.4in .......12.9in ....25.9in ......81.2in ..............780 ..........1.5%
235/45-17 .....4.2in .......12.7in ....25.3in ......79.6in ..............796 ..........-0.5%
215/40-18 .....3.4in .......12.4in ....24.8in ......77.8in ..............814 ..........-2.7%
215/45-18 .....3.8in .......12.8in ....25.6in ......80.5in ..............787 ..........0.6%
225/40-18 .....3.5in .......12.5in ....25.1in ......78.8in ..............804 ..........-1.5%
225/45-18 .....4.0in .......13.0in ....26.0in ......81.6in ..............777 ..........2.0%
235/40-18 .....3.7in .......12.7in ....25.4in ......79.8in ..............794 ..........-0.2%
215/40-19 .....3.4in .......12.9in ....25.8in ......81.0in ..............783 ..........1.2%
215/35-19 .....3.0in .......12.5in ....24.9in ......78.3in ..............809 ..........-2.1%
225/35-19 .....3.1in .......12.6in ....25.2in ......79.2in ..............800 ..........-1.0%
235/35-19 .....3.2in .......12.7in ....25.5in ......80.0in ..............792 ..........0.0%
215/35-20 .....3.0in .......13.0in ....25.9in ......81.4in ..............778 ..........1.8%
225/35-20 .....3.1in .......13.1in ....26.2in ......82.3in ..............770 ..........2.9%
235/35-20 .....3.2in .......13.2in ....26.5in ......83.2in ..............762 ..........4.0%

Anything bigger than a +/-2% difference is considered a mismatch and should be avoided if possible. Speedometer, odometer, and VSA/ABS systems can be affected by mismatched tire sizes.

Generally speaking, when you reduce the tire's sidewall to compensate for a larger wheel, the ride quality will diminish. Some may argue that point but that's why I said generally.

The less rubber that is between the wheel and the road, the more stress is being applied to the wheel itself. Watch out for potholes if you reduce the sidewall of your tire. A forged rim is generally going to be stronger and resist bending better than a cast wheel.

Thanks to the Miata Tire Calculator for the spreadsheet.

Centerbore:
The Tire Rack did an excellent job of explaining centerbore so I'll just copy and paste their explanation here:
The centerbore on the OEM TSX wheel is 64.1mm. Many reputable wheel/tire shops will cary an assortment of hub rings to fill the gap between the centerbore of the aftermarket wheel and the OEM hub. A set of hub rings will cost about $20 and IMO that's money well spent. An out of center wheel will behave much like an unbalanced wheel (it actually is unbalanced because it's rotating around an off-center axis).

As a side note, RonJon wheels are machined to the correct centerbore for Hondas and Acuras so they won't need hub rings.




So that's about it.

Let's try to keep the fitment discussion in this thread and I will revise the first post as need be. It would be good to have a few "boundary cases" where people have tried wheels and tires outside my suggested guidelines so we can develop a “will fit/won’t fit” list.

Cheers,

Dan

Kighter

Will Fit:

2004 TL A-Spec Wheels/Tires

18 x 8.5 +45 wheels.
235/40-18 rubber.

No rubbing or issues other than the extra wide wheel is more exposed to damage and sticks out a little bit. A cosmetic problem for some people, a plus for others.

In 2005 (and presumably after) the TL A-Spec Wheels/Tires were reduced in size to 18 x 8".

xizor

Add 225/45/18, people ask about it all the time.

"Fit" is a subjective thing. Those wheels stick out of the fender some but don't rub w/ a mild drop I imagine. IMO its not to be recommended.

Dan Martin

It's in the list.



I don't think the wheel width really matters as far as rubbing is concerned. I think the determining factor is tire width. Don't we have a few members with +45 offset wheels and 235 rubber?

xizor

225/45-18? Am I just missing it?

I agree on the rubbing part. But when I mean fit, just because it doesn't rub doesn't mean it fits the car if the wheels themselves are outside the fender. Its not a problem anymore though since the 2005 A-SPECS are out now however.

Dan Martin

I thought it was 17. Updated....


on both points.

virtualbong

This is a great thread! Thanks Dan for creating it! I guess I'm going to look for 18x7.5s that have a higher offset of 42 and the tire spec will be:

215/45-18 .....3.8in .......12.8in ....25.6in ......80.5in ..............787 ..........0.6%
225/40-18 .....3.5in .......12.5in ....25.1in ......78.8in ..............804 ..........-1.5%
235/40-18 .....3.7in .......12.7in ....25.4in ......79.8in ..............794 ..........-0.2%

I'll probably be leaning towards 215/45/18 since that has the closer to stock sidewall and the difference is not that great. I know the 235s would give the car better handling, but I'd have to find a pretty high offset to keep it within the wheel well. I guess I'll start surfing now! LOL

virtualbong

What are people's thoughts on 215/40/18 with a +42 offset? Does anyone have this setup on their TSX? If so, please PM me pics at different angles, thanks!

Dan Martin

You'd want at least a 215/45/18 because the 215/40's are too small.

virtualbong

Ok, I'm also going to look into 225/40/18.

So the +42 offset is fine? I just don't want it to be flush with the fenderwell trim.

Dan Martin

You might want to check out this thread: https://acurazine.com/forums/showthread.php?t=19540

It sounds like everything fit nicely with 215/45/18 on 42mm offset wheels but the pictures are broken.

TSX 3Pedal

The first post is pretty comprehensive.

funkbucket007

Has anyone had any success at all mounting 18" x 8" rims with an offset of +40mm?

xizor

they would go on ok, but its not optimal

cmf

Does anyone know what offset to look for on an 8.5 inch wide wheel? I would assume the offset would need to be different than 8 inches, no?

Specifically, I am trying to find offsets that will work on 19 x 8 and 19 x 8.5 inch wheels.

xizor

Use the tire calculator and see how much different offsets change the inner and outer clearence. Compare it again your wheels or the OEM ones and you can eyeball your car to see if whatever offset will work. Also try comparing the 19x8.5 against dzuy's and vwong's 19x8's, dzuy's is +43 and vwong's is +40.

Dan Martin

The higher the better. The main factor that determines if your tires will rub is the tire width, not wheel width. If people can use a 235/35/19 on a 19x8x+45 wheel I don't see why you couldn't use the same tire on a 19x8.5x+45 wheel.

cmf

But if the wheel is wider, then it should change the offset, correct? The wider wheel will stick out further then a skinny wheel... ie 17x7 (OEM) w/ 55 offset vs 18x8 w/ 45 offset.

Maybe I'm making it difficult myself.

cmf

I'm retarded, and your calculator helped out a bunch after figuring out how slow I am to operate it. It ends up being .39 inches more on the outter w/ a 40 mm offset. So I guess I need to stick to a 45 mm or so and that will only take it out .19 more.

Thanks guys!

xizor

Just a FYI for others, offset is measured from the center of the wheel. So a 19x8 and 19x8.5 +45 both have the same distance from the center of the wheel. The 19x8.5 will stick out .25in more on the outside and inside, but the tire will be mounted exactly the same on both wheels. So like Dan said, if the tire fits on a 19x8 +45, it'll fit on a 19x8.5 +45

cmf

Makes sense, as well as the calculator.

See, you guys are full of good info. Thanks again, time to find wheels that will fit now.

AlterZgo

The tire will be mounted in the same place, but the actual width of the tire may still vary depending on the width of the rim it is mounted on.

For instance, a 235-35-19 tire mounted on a 19x8 +45 rim may have an actual footprint width of about 8.3". If you mount that same identical 235-35-19 tire on a 19x8.5" +45 rim, the actual width of the tire may be 8.7" wide. If you mount it on a 19x9 +45 rim, the tire would probably reach the full rated 9.25" width.

Therefore, you may run into some clearance issues with a slightly wider rim even if the tire and offset remain the same.

I didn't think there would be such noticeable variation in width, but I recall seeing pictures of a 225-50-16 tire mounted on various rims from 7" to 9" in width and there was close to a 2" difference in actual width of the tire once mounted on the rims.

Another issue is that the actual width of the tire varies by brand. Not all 235-35-19 tires will have the same exact width. Also, some may have a more squared shoulder whereas others will have a more rounded shoulder which would cause less rubbing.

Dan Martin

It's true that a tire will be wider, but when you stretch it wider, the height also goes down.

virtualbong

Let me know if I'm calculating this correctly on fitment...

1 inch = 25.4 mm
1/2 inch = 12.7 mm

Stock rims are 17x7 with a 55mm offset

Rims that are 18x7.5" with a 40mm offset

Rims that are 18x8" with a 48mm offset

So using this conversion, the 18x7.5" with a 40mm offset would be more inside the wheel well than the 18x8" with a 48mm offset, correct?

xizor

use this. you have to remember that since an offset of 0 is in the middle of the wheel, going from 18x7.5 to 18x8 increases the inside and outside by .25in. .25 is roughly 6mm, so w/ a 18x8 +48 you're going out 6mm for the width, then going 8mm in for the increased offset

virtualbong

Oh God, this is bringing me back to elementary mathematics, LOL.

Just to get things straight. So it would basically be the same as having a 18x7.5 with a 42mm offset, correct?

Sorry for being a stupidass...

xizor

, the wheel calculator will confirm everything

TSX 3Pedal

I'm sorry, but I couldn't find the weight of the stock TSX wheel alone

Dan Martin

24lbs

TSX 3Pedal

Thanks...
Ohh and what about the weight of the stock Michelin's?

Dan Martin

They list at 23lbs but I've read that people have weighed the combo at 46lbs so they might actually weigh 22.

TSX 3Pedal

Thanks for the help

Stokeless_TSX

the 19x8 with 235 35 19 tires rubs if you have more than a 2 inch drop. And its about a half inch taller than the stock tire. I raised my car just to fit mine on, but once i get my fenders rolled i will lower it back down a few turns. =)

Dan Martin

Good to know. What's your offset stoke?

Howard911s

HI! im thinknig about getting 18 inches with 225 40 18... since tire will be bigger and wider. has anyone experienced steering change>? such as looser. more play. or loose that on center feel? it happened to my integra before... i would love the new rim look. just hate to loose that on center feel....

PixelHarmony

Nice post Dan

Too bad I have no money to venture into the wheel department right now.

super jumbo

I was looking into doing a 20X8.5 Is this a no-go?? I talked to some people that recommended doing a 20X7.5 but I can't find any in the style I want. Thanks.

SWRT

If you maintain offset you will not notice a loss in on centre feel.

The lower sidewall will improve response, which is part of on centre feel, this can compensate for some of the lost feeling when switching from +55 to +45 offset.

Whats really happening when you mess with offset its you're moving your contact patch outboard. This increases your scrub radius.

On cars with lots of SAI and caster, increasing scrub radius can actually maintain on centre feel because of the vertical motion of the wheel centre through your steering sweep.

On the average car you will notice lighter steering off centre, and more inputs from your tires (imbalance sensitivity will go up, impacts to one side will be directed through the steering wheel with more force...)

The average joe can't feel the difference between steering response, and on centre feel. They're roughly the same thing, with the exception that the former has more to do with the whole car, the latter is mostly in the front end geometry and the steering assist tuning.

Reduce sidewall = Increase steeringt response

Increase Scrub Radius (caster >4deg) = Reduce on Centre Feel


-SWRT


Can someone running 235/40/18 with +45 offset PM me, I'm hearing people say it can be done, but I'd like to speak with someone first hand.

Powered by Honda

So when using the tire calc it says : Wheel Outboard increase (inches): 0.5

So does that mean my tires will stick out half an inch from the fender? Wont that look nasty? 18/8.0 rims 235/45/18

Dan Martin

You've selected a wheel that is 1" wider than stock. Half of one inch is on the outboard side and the other half on the inside. The offset will determine how much your wheel will stick out compared to stock.

Keep your offset around +45 or higher and you'll be fine.