Hello i’m a newbie and i’ve recently bought some 15x9 4x100/114.3 +0 offset for my rx7 fb and was wondering how many inches i need for wheel spacers to be an exact fit on the car (if anyone is running this offset and size together), i currently am running zg flares and i have 195/55r15 tires to go along with it, I’m thinking around 3 inches is what i’d need maybe? i was going to purchase some spacers test fit it but can’t find a reliable shop to purchase them, even if no one is running this size it’s fine.. i at least need help with the spacers that’ll fit 4x100/4x114.3 pattern, thank you for any information you guys provide.

 

i think the norm is like -20 offset, sooo, 20mm?

 

Thanks for your reply
I’m trying to find a reliable shop that sells 4x110 to 4x120 wheel adaptor, i also think 3 inches would be too much so scratch that, i need like 1inch/1.50 maybe.

 

How wide are the ZG flares? Say they extend 2.5" a 15x7 with a positive offset of 20mm fits the stock body. 15x9 with 0 offset will poke approx 46mm or 1.75". So, you're close. 1" spacer would give you a total -25mm offset. and stick out past the stock wheel opening 2.75"

 

Wheel adapters are a real pain to make, not surprised you are having a difficult time finding someone to make some. I made my own and it was a lot of work.

There are a couple of practical limits you need to keep in mind. 20mm is about the practical lower limit of thickness to have a robust adapter, anything thinner would be too weak. With 20mm adapters you must grind off much of the head of the lug bolts you use to mount the adapters to the hubs and clear the wheels, you can see how tight it is with a 20mm adapter.



The next limit you must deal with is tire clearance between the front tires and struts.

I had plenty of room in the rear wheel well and because of my unique brake system I already had a 12mm spacer under the rotor, so I made those adapters 20mm thick. On the front I was fighting tire rub on the struts, so I had to make those spacers very thick at 40mm


In my case I used 15X9 +35 wheels since those are what fit Miata’s, so they are readily available and relatively cheap. I will be moving to 15X10 +25 since that is the new standard for wide racing Miata wheels. these wheels work with 245-40-15 tires which are becoming much more common nowadays.

It seems likely that with your setup +0 wheels you could get by with 20mm thick adapters front and rear. If you did end up with tire rub on the struts thin 5-10mm 4X100 spacers are cheap to dial in exactly what you need.

 

I use adapters so I can use Miata wheels. The adapters are 25mm thick, bolted to the stock rotor/hub. I have 2.5" springs in the front and camber is set a -2.5 deg. With 225-45-15 tires on 15x7" wheels, I can use ET30 to ET38 wheels. The ET30 pushes the limit in the front and rear on the fenders and ET38 pushes the limit on the inside up front. You should be able to do the math from there to see what works in your situation. I don't think you can get ADAPTERS thinner than 25mm. I use adapters from Adaptitusa.com. I like the way they use "shoulder" lugnuts to hold the adapter to the wheel. In my mind anyway these bolts provide more support surface for the nut. I have a lot of racing miles/hours on mine. The only failure occurred when I inexplicably only installed 3 of the 4 lugnuts holding the adapter to the hub. Go figure.

Good luck.

Carl