so i been wondering what the offset of my wheels are...
i have 17X8 wheels and hankook ventus 215/50/R17(<LINK) tires. i measured the hub surface contact area to the outside of the inner rim. i got this info from HERE. when i measured i got 4.5 inches...but im confused?? how do i know what my offset is so i know the best setup i can get for tire size??
soooo.....
17X8 rim
measured from inner hub to outside of inner rim 4.5 inches

so whats my offset?

 

your offset is anywhere from 0 to +15. you have 4.5" of back space. what kind of wheels are they?

 

i had them for years, actually they came off my old car.....they just happened to fit...
they are Ebay cheapo'S....

they are volution racing wheels

 

you sure it doesn't have a "ET" stamped on the back of it somewhere?

need to know the actual width of the wheel before we can give you an answer

before you say its 8", the reported wheel width is bead seat to bead seat, not face to face

 

i found the ET on the rim.


another spoke had 17X7 stamped
so i assume i measured wrong....

 

One confusing aspect of wheel sizes is that offset is a relative measurement from the center of the wheel to the mount surface. One would think that you could simply take half the wheel width, plus or minus the offset (depending on wether it's a positive or negative), and get the front or backspacing.

The problem is that the stated wheel width is typically the inside of the bead to bead... which doesn't account for the wheel lip which varies from design to design, and makes it difficult to tell what the exact amount of needed clearance will be. For instance, the average "10 inch wide" wheel is actually more like 11" from lip to lip.

 

i just need as much rubber in the rear (will be a 400WHP DD) as i can fit sitting flush to the fender without rolling or rubbing. ill add spacers if needed. and the front id like to have a nice size but dont want to wide of tire since i have a manual rack for steering.
all this and have it looking decent. im going with eibach springs on tockico non adjustable shocks and struts.

 

iirc 225 is max recommended

ppl have done 245 on a 7" but i don't know if you want to do that

for a 400hp car, i would personally prefer a wider tire than a 225 :P

 

thank ya sir. ive read somewhere warnings on runinng to wide a tire on a wheel. whats the problem of running to wide a tire?
so 225 is the "widest" recomended....
what about height? i dont want a super tall tire but id like to fill the fenders....

 

you can run 275's out back on ~35mm offset. you'll want wider wheels tho..
if you're on a budget, i'd get 98-02 mustang GT wheels. theyre light, look decent, and you can fit 245 front and 275 rear (with some rolling). 275 is a bit wide for them, but doable.

 

right now im on a "budget" untill next summer.if 245's outback wont even be near enough rubber then ill stick to what i have and save for rims next summer....

 

with 400hp it doesnt matter how wide your tires are- you wont have enough.
only race rubber will hold the power in 1st and 2nd.
with 305whp i spin 275's through 2nd, a little in 3rd, and chrip 4th.