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Installed RCF wheels. Got some questions.

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Old Dec 8, 2020 | 04:26 PM
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Default Installed RCF wheels. Got some questions.

I just bought a set of RCF wheels from another member and attempted to throw them on there as I had been told they would work just fine. The rear seems great but the fronts hit the control arm assembly. So first question is, does anyone know what size spacer I would need to clear it but not go too crazy with like 25mm? Wheel sizes are 19x9 +50 and 19x10 +41

Also, the tires that are on there are RCF sizes. 255/35/19 and 275/35/19. My car is AWD and since it’s not normally staggered I want to make sure this tire sizes won’t create any issues.

Thank you

Added some pics in case you guys want to see how it looks.



Front

Rear


Really happy with how it looks though!

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Old Dec 8, 2020 | 05:25 PM
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right now you have 18mm less clearance from the stock wheel. measure how close the stock wheel is to the control arm. take that number and calculate the spacer/adapter you need.

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Old Dec 9, 2020 | 06:50 AM
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I agree with kietlander and he's correct. You have ~18mm less clearance in front and if it's hitting, theoretically, a 20mm spacer would fix it.
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Old Dec 9, 2020 | 06:55 AM
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I did some searching and someone else on here thought he had the same issue until he put all wheels on and got it of the jack. I guess the wheel then sits at a different angle and therefore a little more clearance. I’m going to give that a shot first. Then again, they do sit pretty in deep compared to the rears so a 20mm spacer might be a good option. Any recommendations from anyone on some? I’ve never ran spacers so not sure what to look for there.
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Old Dec 9, 2020 | 07:20 AM
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You can't run those mixed sizes on the front and rear axle with AWD. You're going to wreck your diff.

1.7inch circumference difference is massive. Subaru AWD tolerance is 1/4".

Tire Size ComparisonSpecification Sidewall Radius Diameter Circumference Revs/Mile Difference
255/35-19 3.5in 13.0in 26.0in 81.8in 775 0.0%
275/35-19 3.8in 13.3in 26.6in 83.5in 759 2.1%

Last edited by er34; Dec 9, 2020 at 07:25 AM.
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Old Dec 9, 2020 | 07:26 AM
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To determine thickness of spacers, you can stack up few washers.




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Old Dec 9, 2020 | 07:28 AM
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Originally Posted by er34
You can't run those mixed sizes on the front and rear axle with AWD. You're going to wreck your diff.

1.7inch circumference difference is massive. Subaru AWD tolerance is 1/4".

Tire Size ComparisonSpecification Sidewall Radius Diameter Circumference Revs/Mile Difference
255/35-19 3.5in 13.0in 26.0in 81.8in 775 0.0%
275/35-19 3.8in 13.3in 26.6in 83.5in 759 2.1%
This is what I was afraid of. What sizes do you recommend instead?
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Old Dec 9, 2020 | 07:35 AM
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Would this be ok?



Last edited by DiezDos; Dec 9, 2020 at 08:04 AM.
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Old Dec 9, 2020 | 11:05 AM
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Originally Posted by DiezDos
Would this be ok?

Still more than 0.5" difference, but I suppose it might be smaller considering you have some tread wear already on the rear tires.

I don't know anybody here can really tell you definitively whether it will be fine or not since the manufacturer recommends same size tires for AWD.

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Old Dec 9, 2020 | 11:13 AM
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I would go with 245/40, it’s a better match to the rears than a 235/40.

now for the wheel adapters, I would get 15mm and not the 20mm. The 20mm might makes the fronts stick out more than the rear.
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Old Dec 9, 2020 | 11:16 AM
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Here's a compiled list of Eibach and H&R spacers.

https://www.clublexus.com/forums/is-...d-h-and-r.html
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Old Dec 9, 2020 | 11:25 AM
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Downsize the front as indicated above and you'll be fine.



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Old Dec 9, 2020 | 11:27 AM
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Look up the IS, as the AWD IS comes with a staggered setup. I think the circumference is within 1% or so if I remember correctly.
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Old Dec 9, 2020 | 11:34 AM
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Originally Posted by primavera
Downsize the front as indicated above and you'll be fine.


Yeah after my post I looked up these sizes and found them also to be a better match. The numbers look close to an IS AWD staggered.

thank you all
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Old Dec 11, 2020 | 03:37 PM
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So IS AWD comes with staggered and GS AWD comes with square setup?
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