groovyjay

I'm just about to order the wheels from company called hotrod usa. The wheel are TT II2s in 20" diameter. I'm going to get 8" wide wheel in front and 10" in rear. I think I should be fine with 4" back space in rear, is this correct? How'bout front? Is it any different, and I can use 4" as well?
ANOTHER QUESTION: What does BACKSPACE DEEP REVERSE mean???
Hopefully someone can come up the right info on this quickly.... :cheers:
TIA Jay

flynhi

I think the correct OE backspacing is 4.5".

groovyjay

I'm using offset trailing arms so does this make any difference?!?!?!?!?!?!? CAN I GO FOR4.5" in rear!?!?!?!?!?!?
Quickly guys!
Thanks again!

Lohkay

Offset trailing arms should let you put more backspacing. Hope ya get your answer fast.

INTIMIDATOR ZO6

You could just measure the back spacing of your wheels :D Factory back spacing is 4"s ...With the offset trailing arms you just might be able to pull it off with 4.5" back spacing :cheers:


[Modified by Intimidator454, 2:48 PM 1/11/2002]

Neo Fender

I believe it means that the wheel has even less backspace (in other words, the wheel is mounted with more offset, further away from the centerline of the car).

groovyjay

This is getting way too complicated. Is there anyone using 10" wheels with offset trailing arms??

454Big

Jay,

its not this difficult!

Imagine the wheel when you stand behind the car.
The exact half from horn to horn is called the centerline.
Backspacing results in the difference of centerline to the wheels mounting flange. Which can be positive or negative - this means the flange is more to the outer side of the rim or to the inner side of the rim.
This is different from wheel to wheel.
Centerline on a 10" rim is exactly at 5"
Centerline on a 8" rim is at 4" (always the half!)

What you need to check is how inches you can afford to look to the inside of the car (limits here are often the trailing arms [not in your case, not with the offsets] or the Spring and the mounts.
In the front the steering knuckles give the limit most times.

I recommend some tries with a BMW rim, this should be easily available in Finland. They have the same bolt circle, so you can use them for measurement.

I hope I could help you this time.

I´m checking for the delivery of your car in frankfurt, but I need a copy of the build sheet. If you can mail it to me???

Z-man

I have the following sizes on my car, with the VB offset trailing arms...

Front 17X8 Torq Thrust II, 4" backspace
Rear 17X9.5 Torq Thrust II, 5.5" backspace

Regardless of how wide your wheel is, I found that 5.75 inches with the offset TAs to be about max. Actually, the frame is the limiting factor. You will have no problems installing them, but they may stick outside the fender more than you want. Mine are 1.5 inches into the wheel well farther than yours would be...

Another consideration - if you have a rear torsion bar, it may contact the wheel... I don't have one.



[Modified by Z-man, 7:11 PM 1/11/2002]

groovyjay

Neo Fender: This is what the add says:TQ II 20X10 DEEP REV
"TORQ THRUST II'S 20X10 WITH 3" TO 4.5"" BACKSPACE DEEP REVERSE FORD/CHE". So IF I can use 4.5" Back Spacing I could use these wheels?!?!?!?!?!?!

groovyjay

454Big: Thanks for your input. Those orinal wheels were always getting on the way, so I moved them to my brothers place, so I don't have any wheels here with me. I can get my original wheels here in two weeks but that is way too late.... :(
I even used to own 750 BMW which I could have used to take the measurements, but I just traded it for V6 Passat, go figure?!?! :lol:
I'll try to email that build sheet to you ASAP.
Jay

groovyjay

Z-man: Do you reckon I could go all the way to 5.5" Back Space in the back??? The tire set up is going to be 285/30/20 do you think I'll be safe with these set up? I'll add the flares only If the wheels stick out too bad!
BTW that is one sweet ride you got there! :cheers:


[Modified by groovyjay, 9:03 PM 1/11/2002]

Matt M

I run 6" backspacing on an 11" rim, but the tire is close to the frame and rubs once in a great while. 5.5" would never hit on my setup, but I don't know if your offset arms are the same as mine. Anyway, if you bought the offset arms, ask the place where you bought them how much backspace they allow. Thats what I did and they told me 5.5". They were exactly right. So I ran 6". :)

Matt M

Also, if you run a 10" wide rim with 5.5" backspace and a 285mm tire, it won't stick out. If you are considering flares, run a 315mm tire and an 11-12" wide rim.

Matt

groovyjay

Thanks Matt M, I got the Trailing Arms from VB&P, should give 2" more room per side so with stock back space which is 4" that would make 6" so shoul I go for 5.5"???

Matt M

yes, even if the T arms allow 6" backspace, the frame will become the problem, so 5.5" is a good choice.

Matt

groovyjay

Thanks Matt. I'll try to order the wheels on monday. I'll let you guys know how it turned out!
Thanks for everyone! :cheers:

Z-man

If your trailing arms are the same as mine and you haven't done any major frame/body work, you should be fine. The best way to judge is to measure your own car. I did it just to assure myself before I ordered. Pop off one rear wheel. Place a straight-edge of some kind flat against where the wheel mounts. If you are mounting 20 inchers (wow) you would mark a point about 10 inches out on the straight-edge, and then meaure inward toward the wheel well to see where the least distance to interference is - check all around almost in a full circle. In my case the minimum clearance was about 6 inches. As I remember, the least clearance was where the frame kicks up and over the rear drive shafts. I allowed about .5 inch to make sure there was enough clearance (5.5) and it worked very well. Since the front standard was 4 inches, I went with that on the front.

Good luck...

groovyjay

Thanks everyone!!! You're are the greatest!!! I ordered the wheels yesterday as I did order all the Clutch parts from Summit, and Summit told me that I have reached my VISAs limit, so now I'll have to wait until I get the bill here so I can pay them. :) :eek: :D
I'll keep you posted along the way!
Jay

Neo Fender

I would assume it would fit, just don't hold me to it if it doesn't. :bb