woodonastick

iTrader: (1)

sorry, not talking about 1/4miles. im asking for wheel width. im planning to get some 15x8 but not sure about offset. im going to flare the front fender but i still need to find out the offset so i can order them soon. can anyone help me please?

wrxracer55

iTrader: (3)

I'm interested in the specs also, as I was wondering if you can run 8 in wide rims. Can it be donw with out flares? Please post wheel/tire specs.

DriveFast7

iTrader: (1)

my rx7 below has 13x8's with 4" backspace. and they stick out a bit. 225/45/13 fronts, and fatty slicks in back.

I think 3.25" backspace would tuck them under the stock fenders.

mikey D

easier to run big wheels in the rear...in front you run into problems with things rubbing on springs and whatnot

85rotarypower

I don't think they will fit even in the rear. I've been stuck in those fenderwells long enough over the past 2 years to know. I slapped the 205/60R13 BFG radial t/a's I have on the rear of the car and they were about a half inch away from the suspension parts and without rolled fender lips they rubbed. On the rear, it might JUST be possible if you get JUST the right offset. But on the front, its not going to happen. I have some American Racing Outlaw 1 wheels that are 6" wide and I'm going to have some major problems even getting a 205 in there.

I just went out and measured the backspacing actually and its about 3.5". Stock is probably about 4.25" backspacing, mabey more.

Drivefast7, you missunderstand backspace. The backspace you mentioned would set the wheels out even further.

woodonastick

iTrader: (1)

i have a set of over fenders from an old model vw. im planning ot put those on the front so 8ins with fit.

if ur there ruby7 can u tell me ur offset?

TopGunM2k

You'll need to do that...cause they ain't gonna fit in the front with the regular fenders - trust me.

DriveFast7

iTrader: (1)

YOU'RE right 85, 4.75 backspace would tuck them in. thank you for the correction. too much starbucks too early

woodonastick

iTrader: (1)

4.75 backspacing so....20mm off set for front? does that rub anything? or is it close? how bout the rear?

85rotarypower

Offset is different than backspacing. Offset is measured from the rim's centerline. Here is a discription of offset: http://www.diamondracingwheels.com/TermsOffset.htm

Backspacing on the other hand is measured from the rim's rear lip to the mounting surface on the center hub. http://www.diamondracingwheels.com/Terms-BS.htm

Stock offset is -35mm I think. A -20mm offset would set the rim out too far. To fit an 8" rim on the front, you would need something in the range of -55mm or more. That kind of wheel isn't made and it would put the wheel into the suspension. Your better off to look at different backspacing, but I don't think there is any way you can fit that size rim on the front OR the back without putting fender flares on.

Hmmm, I just thought of a way to measure for proper backspacing. If you look at your wheel, the backspace is the distance from the outermost lip to the inner part of the mounting hub. Because of this, the amount the wheel would sit behind the mounting surface on the brake rotor (or drum) would be the amount of backspace. From this, you can do some measurements on your car. Find out how much room you got from the rotor face (where the wheel mouts) to the part that protrudes the most on the suspension (most likely the lower spring perch). From there, you can find out how much backspace you can use (keeping in mind extra space for tire bulge, about 1"), and how much the wheel will stick out. Take the backspace off from the total wheel width and you get the amount of the wheel that will sit in front of the rotor face. Give me a sec and I'll make up a quick pic in paint.

woodonastick

iTrader: (1)

stock offset is +35. i want to barely clear the springs and get an overfender to cover wats left sticking out of the fender. an 8in would have a 0 offset with 4in backspacing. drivefast7 said that a 4.75 back spacing should be ok in the front. so.. the 4in would be already at 0 offset and the .75in is about 20mm. thats why i stated 20mm offset for front.

so wat offset would clear the springs for the front and the frame for the rear? i dont car about the fender because in going to put fender flares on them. the flares i have will give me an extra inch to fit the wheels under. i plan to run 225's all around and possibly 245 someday.

85rotarypower

Ok, here we go. Sorry for the crappy drawing, but I'm a drafter, not a graphic artist here. It only took me about 15 min to draw.



As you can see in the pic, you can easily measure the right backspace for your application. Also, you can see how you can measure how far your wheel will stick out from the rotor mounting surface. Take the total wheel width, subtract the backspacing, and you are left with the "extra width" as I called it. Take the extra width, and measure from your rotor mounting surface out to the extra width amount and see if its past the fender or not.

For example, if you have an 8" wide wheel with a 4.5" backspace, you have 8"-4.5"=3.5". This means the wheel will stick out 3.5" from the rotor mounting surface. Hope this helps you out a little. I should also mention that all measurments should be taken with the weight of the car on the spring as if it was on the ground.

Thanks to Diamond Racing Wheels for the wheel shell drawing I used.

85rotarypower

You still misunderstand offset though. Offset is NOT dependant on backspace. They are two totally different ways of measuring how much of the wheel is in front and behind the mounting hub. Backspace is usually easier to understand.

Disregard that, I read your post wrong.

Anex 570

Holy, this really should be a sticky! Good idea for a drawing, clears alot for me.

DriveFast7

iTrader: (1)

tires like to rub on lower spring perch of 1st gen. the ground control coilover kit with low profile lower spring perch helps clearance.

Phiber Optik

iTrader: (2)

with a 205-40-17 on the front +40mm offset my wheels have about a 3/16" clearance between the spring perch on the front, but there is absolutely no rubbing, even at complete lock!

I would try a +45mm if you have bigger rubber up front,


while we are on this topic what is the largest rubber you guys have fit out back without sticking outside the fender?

85rotarypower

Biggest I have heard of is 225 in the rear.

The height of the sidewall is going to have an affect on how much space you need to have between the spring perch and the tire. A tire that is the stock 185/70R13 has a taller sidewall than a tire of 205/40R17. The 40 series sidewall will be about 1.5" tall, while the 70 series sidewall is about 4" tall. While cornering, not just the part of the tire closest to the contact patch will flex. The whole tire flexes in or out depending on the turn. If you ever watch F1, take a look at the slow motion shots of the cars going through turns. You can see exactly what I am talking about. Anyway, the 70 series tire will obviously flex much more than the 40 series tire due to the amount of rubber there. There are also more unnoticed effects of the wheel itself flexing, but I wouldn't account that into your spacing because the amount is so small you wouldn't have a problem with it unless your wheel is within thousands of the spring perch.