20x10.5 on 4 corners

[zach_435]

Just got my new wheels on yesterday pretty impressed with the how well they fit

They are Ferrada FR1's 20x10.5 et 25 all the way around

Tires are nitto nt555 extreme zr 255/35r20

[Courier6]

Very nice!

[AJP turbo]

Nice looking wheels but a bit of a stretch fit for the tire wouldnt you say?

Id run at least a 275 or 285 at a minimun for 10.5....driving aggressively like i do id be afraid of popping off the bead...that tire is undersized according to most literature and guides for tire sizing

[zach_435]

the stretch it pretty minimal. And if i want to drive it hard i have a different set of wheels for it for that reason. But just to daily it i want it lower then most and a really clean fitment

[AJP turbo]

U call it minimal i would disagree.....i would figure you need a tune adjustment to dial in the speedo and calculations for the trans shifting...these new tunes have an adjustment for millimters of circumference not revs per mile...but u have to do some back figuring becaus the tire manufacturer gives revs per mile for a loaded tire then you need to calculate the millimeters of circumference based on that

You have made the tire quite a bit shorter

[SHOdded]

Put up some numbers, AJ, let's see what we are dealing with   Anything that can't be accounted for/handled in the tune?

[Blackhawk]

They look very nice but man I would be  so afraid of curb rashing them with a narrow tire like that.

[AJP turbo]

Ok when i get home...the other day i calculated for 255/45/20 because i need new shoes soon and i may go with those and i know some of you already have those so i was going to throw out the numbers i calced out and ask if any of u saw a speedo discrepancy with gps....its a considerable change because the section in the tune wants mm of tire circumference

Although if the tuner enables end user options you may have an adjustment for revs per mile so the device must make a change because the actual tune wants mm of circumference

[zach_435]

here's the stretch

[SHOdded]

I wonder how much tire pressure they can handle with this arrangement?  Definitely, the max is no longer 55.  If 35 is "over-inflated", wear would be uneven.  Hmmm ...

[CroR1]

OP, I like them. Put more photos please from ask the way around the car. And what size tires are you running?

[zach_435]

@CroR1 they are nitto nt555 extreme zr 255/35


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[glock-coma]

Ok when i get home...the other day i calculated for 255/45/20 because i need new shoes soon and i may go with those and i know some of you already have those so i was going to throw out the numbers i calced out and ask if any of u saw a speedo discrepancy with gps....its a considerable change because the section in the tune wants mm of tire circumference

Although if the tuner enables end user options you may have an adjustment for revs per mile so the device must make a change because the actual tune wants mm of circumference

I run 255/45/20 and didn't even bother changing the speedo through the sct x4. Minimal deference.

[AJP turbo]

Ok when i get home...the other day i calculated for 255/45/20 because i need new shoes soon and i may go with those and i know some of you already have those so i was going to throw out the numbers i calced out and ask if any of u saw a speedo discrepancy with gps....its a considerable change because the section in the tune wants mm of tire circumference

Although if the tuner enables end user options you may have an adjustment for revs per mile so the device must make a change because the actual tune wants mm of circumference

I run 255/45/20 and didn't even bother changing the speedo through the sct x4. Minimal deference.

Yeah maybe not a huge difference but when it gets to be 2 mph off it would bother me and the error will grow with speed....I don't know at what point that would be but the OCD in me would want to change the tune when I get knew tires....Also when increasing diameter if you don't change the tune then also your mileage will be lower than actual....Good for ripping people off when you sell but bad for keeping track of doing maintenance on time lol.....Either way the stock number in the tune for the stock 20" tire is 2214 mm and that needs to be 2318 for 255/45/20

That number won't make sense to you if you just use the tire dimension and convert the circumference to mm. That number is derived from the tire mfg. revs per mile for the tire when loaded then back figured to find the circumference that would come from that revs per mile value....And judging from the stock tune value and the revs per mile from the stock tire, that's how it's calculated.

[ZSHO]

It just does not sound feasible to step up to a 0.5 inch wider tire considering the perversions needed,just stick with the oem size and avoid all the mischief if your planning to keep your car for the long haul.  Z