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18x10 Square Offset Question

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3
2
Exp. Type
HPDE
Exp. Level
Under 3 Years
Australia
Hello,

I'm setting up a Mustang S550 for track use. I was originally going to run an 18x11 and use different front and rear offsets (+26 and +52) to make it work as spacers are illegal in Australia. I was planning on a 295-305 tyre.

However, I realised this would be a huge pain for tyre rotation having to go to a shop every time. So I've decided that I'll go for an 18x10 and run a 275-285 tyre with the same front and rear offsets.

Now, I know that 18x10 +40 is the standard default for a Mustang GT and works fantastic for a 275 tyre, but can require a 2-3mm spacer for a 285 tyre. Apex have obviously spent a lot of time working this out. I understand that this offset sits virtually flush at the rear and leaves a bit of a gap at the front.

I'd opt for Apex wheels, but the shipping to Australia kills the affordability.

However I found an Australian brand, Koya, who offer custom offsets. Therefore, if I order my wheels in 18x10 +36 to give myself 4mm extra clearance from the struts I'm wondering if I can give myself room to cleanly run a 285 tyre without needing front spacers but am worried that doing so will cause the rear tyre to make contact with the fender under compression.

I'm wanting to run -2.8-3 degrees of front camber and -1.5-1.8 at the rear. I'm unsure if this would be enough to pull the rear wheel in enough to clear the fender if I go for a +36.

Also secondarily - am I going to regret opting for an 18x10 for the sake of rotation simplicity? Is 285 on a 10 a major compromise over 295-305 on an 11?

I'm planning on running Hankook RS4's or Yokohama AD09's in the first years while the car is dual purpose and moving to a Nankang CRS when I want to purely chase lap times. I'd rather not buy wheels twice.
 
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