questions about differences in EURO/TSX wheels sizes

[fabcat]

I have heard many people notice that the wheels on the Euro look too small. A lot of people seem to think that putting bigger rims on it (and perhaps lowering the car) will fix the look. I don't think it does. I think the whole rim/tyre package (diameter) is too small.

When you look at a side-on picture of Euro, in my opinion the shape of the wheel arch looks like it has been designed for a larger wheel.

Here is an example pic from a review:
http://us1.webpublications.com.au/static/images/articles/i19/1939_7mg.jpg
http://us1.webpublications.com.au/static/images/articles/i19/1939_7mg.jpg

The tyre size of the euro luxury is 225/45 R17

One thing I have never heard compared on various forums (including TSX forums) is that the TSX wheel size is larger (in terms of radius/diameter - the "/45 R17" numbers) compared to the Accord Euro.

The tyre size on the TSX is at P215/50 R17

If you look at a side on pic of the TSX the wheel looks like if fits better and fills out the wheel wells better. It is perhaps a subtle difference but it is noticeable.

Example TSX pic:
http://auto.consumerguide.com/images/autoreview/400x266/2004-Acura-TSX-04801101990004.JPG
http://auto.consumerguide.com/images/autoreview/400x266/2004-Acura-TSX-04801101990004.JPG


This raises a number of questions.

Why are they different for the different (although very similar) cars?

Did honda design the car for the bigger wheels and then later decide to use smaller ones?

Alternatively, did honda design the car for the smaller wheels and Acura just decided they want bigger ones?

What would be the impact of using 215/50 R17 tyres on an Accord Euro considering that the suspension and speedo (and possibly other things) have been set up for the standard wheel size?

Can the speedo be adjusted to correct for larger tyres?

Will using larger tyres cause issues with warrentee/insurance?

Will any forum members next set of tyres use the larger size?

Some things to consider:

According to these web sites, it is legal to use a slightly larger tyre size (at least in NSW and QLD):

http://www.rta.nsw.gov.au/registration/downloads/vsi/vsi09_rev4.pdf

"The outside diameter of the wheel and tyre combination must be no more than 15mm over the largest diameter wheel and tyre combination specified for the vehicle and not more than 15mm below the smallest diameter wheel and tyre combination specified for the vehicle."

http://toymods.org.au/Repository/TechDocs/QLD%20Vehicle-Modifications.pdf
"The rim diameter may be varied from the standard size but the overall diameter of the tyre must not vary by more than +15 mm or -26 mm."



According to this calculater, the difference in diameter is 12.5mm (646.8 - 634.3) and the difference at the speedo would be 2% which seems insignificant to me. ie "When your speedo reads 100kph, your are actually traveling 102.0":

http://www.miata.net/garage/tirecalc.html

However if you put on 225/50 R17 (note the width) it might not be legal as the diameter difference would be 22.5mm (656.8 - 634.3)


So can you guys answer some questions and share you thoughts?

[yfin]

I will try and answer some of the questions but short on time at the moment.

Lowering the car does make a big difference as it reduces the wheel arch gap.

You could use 215/50/R17 if you wanted to (assuming you keep within the allowed overall diameter. Ask a tyre shop before you go ahead as they have a book containing the legal size tyres for every car - every combination you can think of).

Going to that size would, however, be downgrading to a smaller contact patch.

I believe the speedo can be adjusted but this is likely to be very expensive. You are better off buying an Apexi RSM and adding tyre correction.

The 2% difference you are noting is probably closer to the true speed of the Euro anyway. Eg at 100kph you are travelling close to 96kph on the stock tyres (actual speed). With that tyre combination you refer to you are travelling closer to the actual speed of 100kph.

I use 235/45/17. I find that to be a really good size for my 17" rims. Not sure if you can use that with the stock Lux rims as you need 7.5" wide diameter rims. 235/45 gives you the wider contact patch but also a more mushroomed sidewall (looks better). The overall diameter is noticeably bigger too so it fills the sidewalls better. On my previous tyres 225/45/17 I could easily fit 4 fingers under the front wheel arch. Now it is 3 and a bit.

[Suntzu]

Ive got 18x7 225/40 R18 offset 45mm and its about 5mm differenet from stock diameter, so right on the money. Drives and handles well, not harsh at all.

[fabcat]

I will try and answer some of the questions but short on time at the moment.

Lowering the car does make a big difference as it reduces the wheel arch gap.

It does help but I think you still get too big of a wheel arch gap front and rear of the wheel (In my opinion which of course could be wrong) compared to say an M style bmw 3 series. That goes back to my thought that the wheel arch may have been designed for a bigger wheel.


You could use 215/50/R17 if you wanted to (assuming you keep within the allowed overall diameter. Ask a tyre shop before you go ahead as they have a book containing the legal size tyres for every car - every combination you can think of).

Going to that size would, however, be downgrading to a smaller contact patch.

I believe the speedo can be adjusted but this is likely to be very expensive. You are better off buying an Apexi RSM and adding tyre correction.

The 2% difference you are noting is probably closer to the true speed of the Euro anyway. Eg at 100kph you are travelling close to 96kph on the stock tyres (actual speed). With that tyre combination you refer to you are travelling closer to the actual speed of 100kph.

I didn't know that. That is interesting.


I use 235/45/17. I find that to be a really good size for my 17" rims. Not sure if you can use that with the stock Lux rims as you need 7.5" wide diameter rims. 235/45 gives you the wider contact patch but also a more mushroomed sidewall (looks better). The overall diameter is noticeably bigger too so it fills the sidewalls better. On my previous tyres 225/45/17 I could easily fit 4 fingers under the front wheel arch. Now it is 3 and a bit.

That sounds really good. Is there side on pics of your current set up that you can link to. I'd like to see it.

[fabcat]

Ive got 18x7 225/40 R18 offset 45mm and its about 5mm differenet from stock diameter, so right on the money. Drives and handles well, not harsh at all.

I'd like to see that. Got any side on pics of your car that we can see?

It is good to hear that it still handles well. Have you had any suspension mods/ lowering etc to go with that?

[splinter]

I've got 225/40R18
ride is rougher than std setup

[EuroAccord13]

Can the speedo be adjusted to correct for larger tyres?

Yes, you can have your speedo calibrated.

Will using larger tyres cause issues with warrentee/insurance?

Honda can argue that the warranty doesn't stand because it's aftermarket and it changes the ride/suspension of the car as they will tell you that the specified size is best for the car, as for insurance companies, you will need to call and check, generally, they allow 2 inches up.

Will any forum members next set of tyres use the larger size?

I used to run 225/40R18, the ride is harsher but it pimps the car up...


I now run 225/50R16 on my car and the size is the same, therefore no speedo calibration is required....

[razaman]

I don't think you can really notice the difference between the two wheel packages. 0.5 inches is the difference, tyre pressures can have the same impact on the look.

Honda accords have always had wheels packages that look to small for the wheel arches. 4th gens did, 5th gens did, 6th gens did, and now 7th gens do. Honda makes a compromise between ride quality and performance and based on their target market their err on the side of comfort.

I think a lowering makes a huge difference to the look. have a look at these, some with stock tsx alloys and some with aftermarket, makes a huge difference.

http://www.we-todd-did-racing.com/wetoddimage.wtdr/wMTAwOTMwNzZzNDEzZGZkMzF5NTQx.jpg

http://www.we-todd-did-racing.com/wetoddimage.wtdr/wMTAwOTMwNjZzNDEzZGZkMzF5NTQx.jpg

http://www.we-todd-did-racing.com/wetoddimage.wtdr/wMTAwOTMwNTZzNDEzZGZkMzF5NTQx.jpg

Raz

[fabcat]

I don't think you can really notice the difference between the two wheel packages. 0.5 inches is the difference, tyre pressures can have the same impact on the look.

Hmm. Perhaps, but I keep looking at the 3rd picture you posted of the tsx and comparing it to the first picture I posted showing the Euro. To my eyes the overall wheel size on non standard tsx look significantly bigger then the euro wheels. Could be an optical illusion due to the lowering I guess. Those wheels on the tsx's look great by the way. The wheel size seems to suit the car well.

Thanks to everyone who posted answers and comments. I don't have a euro yet but am looking forward to getting one when I can get the funds together. When my tyres need replacing I will definitly look into getting a larger tyre size. I'll consider it anyway.

Fabcat