View Single Post
Old 12-05-2013, 10:00 PM   #339
mwjcyber
Senior Member
 
mwjcyber's Avatar
 
Join Date: Jun 2013
Drives: 13' Subaru BRZ Limited SWP 6MT
Location: Albuquerque, NM (5923 ft)
Posts: 465
Thanks: 515
Thanked 307 Times in 170 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by speedtrip View Post
Ya the sizes I mentioned are what I am looking at I like the idea of the 17x9s but like I said they are +30 offset the poke is what concerns me. The 18x8.5 are a +38 offset so I dont know how much concern I have with that.
I've seen numerous 18x8.5 +38 setups, and all were perfectly flush on the front with a 1.5-2.0" drop.

@DarrenDriven's Flush Wheel Offset Chart is a great reference when selecting wheels, but only provides numbers for a 1" drop. For those 2" drop numbers, I extended the table with its current offset rate, but the wheels will suck in at a higher rate the lower you go; basic geometry of an arc. I plan on accurately measuring the offset change for a 2" drop over Christmas.

Code:
WHEEL   |-- STOCK HEIGHT --|  |-- LOWERED 1" --| |-- LOWERED 2" --|
WIDTH      FRONT     REAR       FRONT     REAR     FRONT     REAR
7.0         +25       +18        +23       +13      +21       +9
7.5         +31       +24        +29       +19      +27       +14
8.0         +38       +31        +36       +26      +34       +22
8.5         +44       +37        +42       +32      +40       +28
9.0         +50       +43        +48       +38      +46       +34
9.5         +57       +50        +55       +45      +53       +41
10.0                  +56                  +51                +47

WHEN LOWERED 1" YOU WILL NEED TO REDUCE THE FRONT OFFSET
BY 2MM AND THE REAR OFFSET BY 5MM FOR PERFECT FLUSHNESS

DECREASING THE OFFSET NUMBER PUSHES THE WHEELS OUT AND
INCREASING THE OFFSET SUCKS THE WHEELS IN.
8.5" wide +38 wheel flushness with 1" drop
F: +4mm (poke)
R: -6mm (tuck)

9" wide +42 wheel flushness with 1" drop
F: +6mm (poke)
R: -4mm (tuck)

8.5" wide +38 wheel flushness with 2" drop
F: +2mm (poke) Although I've seen this flush.
R: -10mm (tuck)

9" wide +42 wheel flushness with 2" drop
F: +4mm (poke) Also seen this flush.
R: +8mm (tuck)

If you're looking to go squared, I'd recommend getting your front as close to flush as possible, and then expect to run a spacer in the rear to flush it out. Otherwise you could go staggered with a larger wheel in the rear, but then you lose the ability to rotate tires, and an increase in under-steer.


Thanks to @switchlanez for the format.

Last edited by mwjcyber; 12-05-2013 at 10:11 PM.
mwjcyber is offline   Reply With Quote
The Following 2 Users Say Thank You to mwjcyber For This Useful Post:
robotickrypto86 (12-07-2013), subwaynm (12-06-2013)