citizen_zero

I want to get 20" rims, but I am getting a headache trying to make the numbers work. Here is a list of issue I am trying to figure out, I hope somebody can shed some light on the situation.

1) to maintain exact overall diameter of 26.0", the tires must be 255/30/20.

Q1) what are the consquences associated w/ increasing/decreasing (i.e. using 245/30/20 to make 25.8" diameter) the overall diameter (other than incorrect speedo reading)?


2) only 20/9 rims fits 255/30/20 tires, which I was told will not fit in the front.

Q2) anyone have 20/9 up front? what's the offset?

Q3) can 20/8.5 fit 255/30/20? how does it look?

Q4) considered using staggered (i.e. 20/8.5 or 20/8 w/ 245/30/20 up front, and 20/9 255/30/20 on the rear), but thats gonna open up a whole new can of worms...

...basically, I want to keep the front/rear same, to avoid chg in steering dynmics due to the 50/50 weight distribution.


3) ride comfort

Q5) how harsh is the ride?

Q6) is there anything important that I missed?

If you got a 20" setup, pls let me know soon... before I blow my brains out. thx


Leo

RXE16T

PM EZZY, he may be able to answer some of your questions since he belongs to the "Big Rim Brigade"

citizen_zero

thx, nojooc

So who is in this "Big Rim Brigade"? I didn't think alot ppls opt'd for the 20"s, but it does look so right on the 8.

dos

I have a set of 20" rims on my 68 Lincoln Continental. Some of the problems you will encounter is busting out the sidewall on your tire and bent rims (I still have a set of the original rims and tires to swap out in winter). I have not yet had to replace a rim, but have lost two tires do to crappy St. Louis roads in the late fall/early winter. Good Luck!!

Kel Rx8

i dont think there is such a club hes just pulling your leg
those teenage rim guy's

if u still need some help
shoot me a p/m

brillo

why not spend the money on a good light weight set of 18''? Your going to hurt your performance and the ride is going to be harsh. The car looks fine with 18, I've seen some decent 19''s but 20 is over the top.

I would think long and hard before going to 20's.

RX8_Buckeye

Just be aware of what you're doing--there are risks involved.

https://www.rx8club.com/showthread.p...rability+risks

EZZY

i think i have replied your PM, but anyway...

we dont have 255/30 tyres, so i have 245/35 for my 20x8.5 all-round. AFAIK, it is only slightly bigger than factory over-all diameter. which mean your actual speed will be less than what on the speedo.

i have 20x8.5 & 245/35 at the front, and i had to roll the front guards/fenders for clearance when i lowered it 2.5".

im sure it will look great


as long as the over-all diameter are the same for front and back, staggered setup isnt a problem. maybe try 245/35 for the front and 255/30 for the rear.
when i had the 19"s, i had 245/35 for the front and 275/30 for the rear, no problems.

atm, i have 30mm lowered springs all-round (instead of the previous 2.5"/2,75"), and with the 20"s, it is still very comfortable compared to factory. obviously on some bumpy roads (we have alot of them here in sydney), you will probably need a sports bra :D

- make sure you have the correct tyre pressure at all times.
- are you happy with the tyre replacement $$$ figure
- wheels come with structural warranty?!? (i get a lifetime structural warranty)
- i'd suggest to lower the car first before fitting the 20's, so you know exactly what offset to get and how much room you got to play with for the tyres.

thats all i can think of atm.....

RX8_Buckeye

Actually, a bigger diameter means that your speedo will read lower than it did with the OEM wheels. Translational velocity is the product of tire rotational speed and tire circumference. Since the speedo measures only wheel rotational speed and is calibrated to the OEM tire circumference, any increase to the tire circumference will not be accounted for by the speedo. If tire cirumference increases by 5%, actual vehicle speed will be 5% higher for a given tire rotational speed.

I don't know if you read the link I provided, but one important thing you should know is that it is very possible that your warranty on suspension components (and possibly other subsystems, depending on the nature of the failure) could be voided by using 20" wheels. The car was designed to handle the loads associated with the OEM equipment, so the manufacturer is not responsible for any failures that might occur due to increased road loads that the car will experience with 20" wheels.

crossbow

Manufacturers have been known to void differential and transmission warranty's on excessively oversized wheels. If you aren't a DIY'er, I suggest talking to your local service manager before considering this modification.

Add 20 lb weights to your ankles and hands, and it gives you an idea of what your accomplishing.

EZZY

thats not a problem for me mate thats why i had the 19" slapped on as soon as i got out of the dealership, and now its getting a new outfit as well as other bits and pieces, and in case you are wondering, im in the car mod business, so i guess i can say im a DIYer