20" Staggered Wheel and Tire Setup

[bobmarley421]

My 3.8 came with 17" stock wheels and tires. Going to 18" is not much of a change over stock so Ive decided to go 20". The 19" stuff is very limited and tire choices and limited as well. Hence why Ive decided on 20". Hoping ride quality wont be unbearable. Anyone with 20" wheels feel free to chime in here.

Ive decided on TSW Nardo 20" chrome wheels in a staggered fittment. Front wheels are 20x8.5 with a 35mm offset. The rears will be 20x10 with a 40mm offset. Most people have suggested going with a 245/35/20 tire in front and a 275/30/20 in rear. However after doing some research Ive fairly sure 245/40/20 in front and 275/35/20 in rear will work as well. I really wanting to keep as much sidewall as possible hoping it will help the ride quality.

Anyone who has a similar setup or suggestions reguarding fittment feel free to expound.

 

[Dicko]

I have a 2012 (5.0) and I have to try on 10 different wheels to fit the large brakes. I went all the way around with a 40 offset and 8.5" x 20" with 245 x 40 x 20 and you feel more of the road inperfection than the 235 x 50 x 18 stock tire but the cornering is worth it. I don't think there is that much difference in the ride quality. When the tires wear out I am buying 9.5 for the rear with 275 x 35 it set in the wheel well better. My car is black with black wheels and narrow silver trim around the edge of the wheel and the bolts to look like a 3 pc wheel it goes good together.

 

[Southern Boy]

You might want to check out the effects of changing your wheel size verses the actual speed of the car.
This is important because tire sizes can affect shifting points and overall performance of the engine ECU. This is a site where you can check the tire size verses the original size.
In my case I went from 17” wheels to 18” and from 225-55-17 to 225-50-18 inch wheels the difference was 0.4% decrease in indicated speed. In other words when my speed is indicated as 60 MPH the actual speed is 60.3 MPH
http://www.miata.net/garage/tirecalc.html
As far as offsets I went with 40 mm offsets, but I could have selected 20mm to 40mm offsets

 

[Curtyrut]

I have a 2012 (5.0) and I have to try on 10 different wheels to fit the large brakes. I went all the way around with a 40 offset and 8.5" x 20" with 245 x 40 x 20 and you feel more of the road inperfection than the 235 x 50 x 18 stock tire but the cornering is worth it. I don't think there is that much difference in the ride quality. When the tires wear out I am buying 9.5 for the rear with 275 x 35 it set in the wheel well better. My car is black with black wheels and narrow silver trim around the edge of the wheel and the bolts to look like a 3 pc wheel it goes good together.

Hello Dicko, can you post pictures? I have the Black/Black RSpec and I am looking to replace my wheels or swap tire sizes to leave a larger footprint if possible. My concern is I do not want to go too much thinner with respect to the tire height since I believe this increases the chances of damaging the rims.
Thanks

 

[bobmarley421]

You might want to check out the effects of changing your wheel size verses the actual speed of the car.
This is important because tire sizes can affect shifting points and overall performance of the engine ECU. This is a site where you can check the tire size verses the original size.
In my case I went from 17” wheels to 18” and from 225-55-17 to 225-50-18 inch wheels the difference was 0.4% decrease in indicated speed. In other words when my speed is indicated as 60 MPH the actual speed is 60.3 MPH
http://www.miata.net/garage/tirecalc.html
As far as offsets I went with 40 mm offsets, but I could have selected 20mm to 40mm offsets

Looks like Im going to go with 245/35/20 in front and 285/30/20 in rear. According to the calculator this will give an identical overall size and rollout as stock.

 

[Dicko]

I checked and the overall size is smaller 265 x 35 x 20 is the same size as 235.x 50 x 18 and I went with 245 x 40 x 20 and it is 27.6" tall where my stock is 27.3 and it is so close to stock

 

[Dicko]

Something is wrong and the site will not let me upload pic's. It must be because I am a junior member

 

[Dicko]

Here we go again (Your submission could not be processed because a security token was missing) this is the message I keep getting and Genesis help desk will not respond to my messages

 

[Delphunkey]

My 3.8 came with 17" stock wheels and tires. Going to 18" is not much of a change over stock so Ive decided to go 20". The 19" stuff is very limited and tire choices and limited as well. Hence why Ive decided on 20". Hoping ride quality wont be unbearable. Anyone with 20" wheels feel free to chime in here.

Ive decided on TSW Nardo 20" chrome wheels in a staggered fittment. Front wheels are 20x8.5 with a 35mm offset. The rears will be 20x10 with a 40mm offset. Most people have suggested going with a 245/35/20 tire in front and a 275/30/20 in rear. However after doing some research Ive fairly sure 245/40/20 in front and 275/35/20 in rear will work as well. I really wanting to keep as much sidewall as possible hoping it will help the ride quality.

Anyone who has a similar setup or suggestions reguarding fittment feel free to expound.

bobmarley, I run 245/40/20 and 275/35/20 on my 3.8 and have no issues although the speedo runs 1 or 2 mph more than my actual speed. The ride quality is very similar to the 18's that were on the car originally

 

[Curtyrut]

Here we go again (Your submission could not be processed because a security token was missing) this is the message I keep getting and Genesis help desk will not respond to my messages

Dicko, I received the same message and was told that message is an indicator that the pictures are too large. I believe you must re-size your pictures or load your pictures to a website called photobucket and this will allow you to post to this forum. I believe that was my understanding. Thanks.

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[Curtyrut]

bobmarley, I run 245/40/20 and 275/35/20 on my 3.8 and have no issues although the speedo runs 1 or 2 mph more than my actual speed. The ride quality is very similar to the 18's that were on the car originally

Delphunkey, nice work! Do you know if the rear would rub with passengers? What is the name of those rims? I was looking at something similar and the website allowed end users to change the colors. For example, black chrome highlights on chrome wheels or the like.

 

[Delphunkey]

Delphunkey, nice work! Do you know if the rear would rub with passengers? What is the name of those rims? I was looking at something similar and the website allowed end users to change the colors. For example, black chrome highlights on chrome wheels or the like.

I've had five 6' tall guys in the car and no issue with rubbing. The wheels are Elite Wheels, Phase 5 by MHT (same makers of DUB and Foose). …And you can get custom colours (I’m Canadian) with some of their wheels, I’m just not sure if these are available in custom colours.

I was originally looking for a different design and my installer came up with the idea to look at these. I’m quite happy I listened to him!

 

[skweak]

i found a set of 20x8.5 and 20x10 114.3 MRR GT1's for cheap...MRR says the pcd is different so they wont fit
they came off an infiniti G35x???
wtf

 

[skweak]

thats what these are!?!