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245/50/20's

Started by Vortech347, November 05, 2015, 12:29:24 PM

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Vortech347

So looks like they are almost a full inch larger in total height.  However I can easily find snow tires at HALF the cost of 245/45/20.

From the looks of seeing people run huge wheels 22"+ going a a little more in tire size shouldn't be much of an issue.

Anyone run this size?
Matt H.
2013 SHO Performance Pack, Daily, AJPTurbo tuned
2003 SVT Cobra 497rwhp/491rwtq, Self tuned, Cruiser
1990 Mustang GT 570rwhp/530twtq, Self tuned, Open Track
2017 F150 XLT 5.0

panther427

I think that is the size my blizzaks are. I will have to double check when I get home. I bought some used ones off Craigslist last year. If so I ran them all winter.
2013 SHO

SHOdded

#2
Based on http://www.miata.net/garage/tirecalc.html

Tire Size Comparison
Specification  Sidewall  Radius  Diameter    Circumference  Revs/Mile  Difference
245/45-20         4.3in  14.3in    28.7in         90.1in        703           0.0%
245/50-20         4.8in  14.8in    29.6in         93.1in        680           3.4%


You are just outside the 3% max variation allowed by the AWD system.  So it's your call, but I would not do it.  You COULD ask a dealer to update the tire size in the PCM, not sure if it can be done without a tune.  But a tuner can definitely update this parameter for you (a relatively expensive way to go just for tire sizing).

You might want to call the seller/mfr to get the actual height of the tire at the specified psi.  Maybe it will fit under that 3%, though I do not hold out great hope for that.
2007 Ford Edge SEL, Powerstop F/R Brake Kit, TXT LED 6000K Lo & Hi Beams, W16W LED Reverse Bulbs, 3BSpec 2.5w Map Lights, 5W Cree rear dome lights, 5W Cree cargo light, DTBL LED Taillights

If tuned:  Take note of the strategy code as you return to stock (including 3 bar MAP to 2 bar MAP) -> take car in & get it serviced -> check strategy code when you get car back -> have tuner update your tune if the strategy code has changed -> reload tune -> ENJOY!

panther427

That 3% is only for running different size tires like front to back.  Or new tires with bald ones.  The taller tire will change your speedometer though
2013 SHO

pmezo33

You could probably buy a pair of new 18" wheels and snow tires for around the same price as those 20" snow tires.  This will also save you the hassle and cost of having to switch the tires on and off the wheels between seasons.  Narrower snow tires will run better in the snow too.

I got a set of 17" wheels and snow tires for $850 out the door from discounttiredirect.  I've got a MKS though.  You'll probably have to go 18's with the SHO.

Vortech347

Quote from: pmezo33 on November 05, 2015, 02:11:59 PM
You could probably buy a pair of new 18" wheels and snow tires for around the same price as those 20" snow tires.  This will also save you the hassle and cost of having to switch the tires on and off the wheels between seasons.  Narrower snow tires will run better in the snow too.

I got a set of 17" wheels and snow tires for $850 out the door from discounttiredirect.  I've got a MKS though.  You'll probably have to go 18's with the SHO.

Can't run 17's tire rack has a close out for the size I posted at around 600$ a set.  I already have extra wheels. My stock ones will now be used for winter duty. I have TSW's coming tomorrow.  Car won't care what size I run as long as it's equal on all 4 sides. Just wondering about any physical limitations.  I can adjust rev/mile in the x4 to keep the speedometer on.
Matt H.
2013 SHO Performance Pack, Daily, AJPTurbo tuned
2003 SVT Cobra 497rwhp/491rwtq, Self tuned, Cruiser
1990 Mustang GT 570rwhp/530twtq, Self tuned, Open Track
2017 F150 XLT 5.0

panther427

Which tire are you looking at?
2013 SHO

Vortech347

Matt H.
2013 SHO Performance Pack, Daily, AJPTurbo tuned
2003 SVT Cobra 497rwhp/491rwtq, Self tuned, Cruiser
1990 Mustang GT 570rwhp/530twtq, Self tuned, Open Track
2017 F150 XLT 5.0

panther427

I have the dm-v1. They are a pretty good tire. The negatives I noticed. But this is on a used set come comparing to stock Michelin. They are louder and less feedback.
2013 SHO