eclipseaudio1530

well soon i am going to be purchasing new rims and tires for my 87 t2. the wheels are going to be staggered 7 inch with +38mm offset up front and 9 inch with +35mm offset out back. I want to run 225's in the front and 255's in the back. My questions for you guys has to do with the sidewalls. sometimes i see people with a size 45 sidewall in the front with a 40 in back. why do people do this? and second is looks. i cant really decide to go with a 40 or 45 sidewall for the rims. i dont want to small of a sidewall because i dont like the look of a tire being streched over the rim but i dont want it to be bulging out much either. thanks for the input.

ddub

My suggestion is to choose your tire sizes to keep the overall diameter of the tire near stock, not merely on looks.

eclipseaudio1530

lol i knew someone was gonna say that. but really either the 40 or 45 sidewall is gonna be bigger than the stock size but just barely, the speedo will be off by less than one mile an hour and plus these rims are lighter than the t2 chunks of metal. i am just lookin for someone with a similar setup to give me some info.

37FC3S

I will be running 245/40 for the front and 255/40 for the rear on my 89GTU. I agree with dDub, try to keep the overall diameter close to stock and the rim width within the specifications of the tire size you want to run. Let me know if your want a picture of the 255/40 on a 17x9 rim to see want it looks like.

Turbonut

iTrader: (1)

Most try and fill out the wheel wheels as the original 205 x 55's are a small diameter and don't fill out the wheels, esp in the rear. Originally Mazda wwas going to use 215 x 55, but at that time, not very many cars used that size.
In the above example the 225 x 40 x17 is over 3/4 in smaller in dia than stock, and the 255 x 40 x 17 is about 3/16's in taller. Quite a difference in size between front and rear. Almost 1 inch. I keep the od very consistant as the car is equipped with ABS which will cause a problem if the od is off drastically.

37FC3S

If Turbonut was refering to my last post as the above example, the fronts are 245x40x17 which are .2" smaller than the rear 255x40x17 tires I have.

eclipseaudio1530

sure man, i would like to see a pic of ur tires. thanks a lot.

eclipseaudio1530

but how do the 225's have a different diameter than the 255's if they have the same sidewall?

grafddrx7

It's not the same sidewall... The 40 is the aspect ratio of the sidewall compared to the tread-width.

40 means that the sidewall height is 40% of the tread width. So, a 255-40 will have a taller sidewall compared to a 225-40.

Turbonut

iTrader: (1)

SORRY-Must be getting old and not reading the numbers correctly. 245 x 40 and 255 x 40 only .32" difference. A lot better than my calculation using the 225 x 40 in error.

eclipseaudio1530

son of a bitch, thanks for clearing that up for me. i knew that the sidewall was the aspect ratio but my dumbass just didnt put two and two together. thanks again.

jgrts20

um actually the rears can only take up to 235's stock and the fronts need spacers to run 225 or higher!! Im running 225's in the front(no spacers) and it rubs on moderate/very moderate turns.

jgrts20

oh by the way the 255 is the width of the tire and the lower the number on the sidewall the less rubber you have on the rim.

eclipseaudio1530

well the front rims are +35mm, that is 5mm more than stock so that is like a 5mm spacer. as for the back i see guys runnin 255's all the time but i guess they have some fender work or somethin.

37FC3S

Here are a couple of pictures of the 255x40s mounted on 17x9 rims. The rims are a +35 offset and double check on the fitment on the official FC fitment post in the tire and wheel section. I have coilovers and I have -2.0 degrees camber in back so, I am not sure if that combination would fit on your FC.

RotaryForce13B

I just bout some enkei RPM2's 17x8 +35 offset on the front and 17x9 +40 offset on the rear. Tires 225/45 front 255/40 rear. I cant wait for them to come in!

If you need help with a set up email Rishie at Auto R & D
sales@autornd.com

spitfire7

when i was into big rims i ran 18s with 225 in the front and 245s and 255s in the back. i do not suggest a tire that is wider than the rim. if u (cruse ) lol than ull b ok. but if ur like most 7 drivers (heavyrightfooted) that tire is gonna buckle, loose tire pressure, rim will make contact with the ashphalt and possably loose controll. i thought i was bumping curbs. i was scrapping the ground. a streched tire a lot more safe because its side wall will not give out. i wrecked my 7 thinking a wider tire is better. get a wide rim if u want to fill out the back wheel well 255 in the back the widest, 225in the front touches a little with no issues.