Rx8Mango

Just a question for you wheel/tire guys out there. I dont know much about offsets and stuff like that. I dont even know what offset means! But some rims that I am looking at getting offer offsets of 45/40/38/30. I read that the offset for our stock rim is 50mm, so is the closer the number the better? Also, I could get 19x8, but I want to go a bit wider. Will 19x9's fit well? Thanks a bunch!

Rx8Mango

can anyone offer any advice?

Efini 8

19x9 might be pushing it, I cannot say for sure, cuz I do not have experience, but my team mate works for iforged alloy wheels and he said just by looking the rx8 SHOULD fit 19x9 in the rear, and COULD fit 19x9 in the front. I suggest getting smaller size just to be safe or at least get smaller widths in the front so if you do u-turns or turns it wont rub against your wheel well.

if you want the rim to 'stick out more' I suggest simply getting a different offset to have them have a wider stance.

Rx8Mango

Thanks for the advice man. Actually, I just talked to some people at Tirerack, and they said I should stick to 19x8 with 45mm offset just to be safe. So I am gonna just go 19x8's all around with 45mm. Will post pics once I get them!

Hercules

I don't see much point in putting a 19" tire when you won't get any performance gain, and will actually increase your likelihood of bending the rim.

Just my $.02.

mikeb

Its called style

AAS

I also was thinking of replacing my 18" to 19". I want to close the gap between the wheel and the fender as much as I can.
Anybody know what to do with the tire pressure sensor? I called TireRack, and they told me - "We don't know which wheel will accomodate this sensor".

Any suggestions, on which wheels are compatible with this stupid tire sensors?

Thanks you
Nick

ciccone376

^^ummm...going with a 19" wheel that fits within acceptable %'s of the stock 18's (i.e. has the same overall diamater for speedo and ABS calibrations, should be less then 1% I believe) WILL NOT reduce the gap in your wheel fender. Actually the lower profile tires will give you a VISUAL perception that the car is RAISED.

Going to a larger wheel/tire within the correct SAFE percentages of stock does not really change the overall height of the tire. It changes the diameter of the WHEEL whilre reducing the profile of the tire's sidewall.

If you don't lower the car, the gap will stay the same.

This isn't like putting new tires/wheels on a truck, whereby you are actually getting LARGER diameter tires that are physically taller.

Also, people should REALLY make sure you are buying wheels that are HUBCENTRIC or come with quality made hub centric mounting rings.

Too many people buy crap wheels that can fit their car but aren't hubcentric and have issues with balancing. Also make sure the bolts/lugs are the proper seat design.

I have bought wheels for all my previous cars and have given a lot of advice to my friends. YOU GET WHAT YOU PAY FOR and DO YOUR RESEARCH.

Ciccone

mikeb

good informative post man

AAS

ciccone376 - Good information.

But I don't understand, why can't I get 19" rims and tires with the same sidewall size as it comes with 18". It should fit because there is plenty of space, and the fender gap will be decreased.

ciccone376

sorry for the late response.

your cars ABS and Speedometer (among other things) are calibrated to the overall Diameter of your tires/wheels. Lets say you have 18x8 with 225/40/18's. In order to stay within 1-2% of that diameter...if you wanted a WIDER and larger (19") tire, then the sidewall would have to be reduced.

By the way..the 225 is the number in MM for width of the tires, the 40 is the number in MM for the profile and is a percentage of the width.


Go to this website:
http://www.csgnetwork.com/tireinfo4calc.html

you can put in the stock tire/wheel size and then put in a new tire/wheel to be compared to. This calculator will give you all the specs and estimate the % difference. I would recommend staying within a 1-2% difference range (you should be fine with a -1% also)

If you want the SAME sidewall as the 18's, but in 19's..it will throw off the diameter.

Also, people are talking a lot about offsets. Please keep in mind OFFSET is very very important in the wheels fitting correctly, both on the car and to allow proper room for the brakes. i would go to TireRack to learn about offset, since its a pretty complicated little word and they have a nice easy diagram that explains it.

if you have any other questions let me know. I'm not an expert, but I've done enough to my cars and been around the block many times to know what is and isn't good.

take care
Ciccone

RobDickinson

Slight clarification.

"40" is the tyre height as a percentage of width. i.e. 40% of 225mm. The 40 itself isnt in MM, inches or foo.

ciccone376

^yup, Rob is right.

Thanks for correcting my mistake...i was typing too fast.

Ciccone

AAS

Thank you for clearification.
And thanks for the link to calculate tire dimentions.

I guess I'll have to drop the car. I just hope it's not going to be too low for the New York roads

mikeb

just drive with extra caution