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Is your speedo off or correct? I swear it feels like I'm crawling at highway speeds. I had my wife download a GPS app with speedo on it and it's spot on. The larger wheels had me wondering if there was a need for a speedo correction.
I don't even recall the last time I looked at my Speedometer. Use Waze for this and have an alert set when I exceed 90mph. Been dealing with oversize tires all my life, and the Speedo is never correct once you make that jump. My Dodge Cummins is off approximately 8mph after going to 35s. My F is off about 3-5 mph after going to 20s. Its the price you pay for good looks!
Rcf factory tires are 35's front and 30 rear in the rears on 19" wheels. Mine are the same on 20" wheels. What other than that do you need to know? Width won't matter for my question...
Rcf factory tires are 35's front and 30 rear in the rears on 19" wheels. Mine are the same on 20" wheels. What other than that do you need to know? Width won't matter for my question...
The tire width absolutely does matter. Any time you add width to the tire you slightly increase overall diameter and sidewall height. By your logic a 255/30/20 and 305/30/20 are the same height because they are both 30 series tires. The overall diameter of a 255/30/20 is 26" while a 305/30/20 is 27.2", big difference.
So why Lou is asking that is so he can see how far your tire heights are from a 255/35/19 (26") and a 275/35/19 (26.6") which are the stock heights. If your 20's are taller your speedo will read lower. Plug your full tire size in to any online calculator like stated above and you will have your answer.
The tire width absolutely does matter. Any time you add width to the tire you slightly increase overall diameter and sidewall height. By your logic a 255/30/20 and 305/30/20 are the same height because they are both 30 series tires. The overall diameter of a 255/30/20 is 26" while a 305/30/20 is 27.2", big difference.
So why Lou is asking that is so he can see how far your tire heights are from a 255/35/19 (26") and a 275/35/19 (26.6") which are the stock heights. If your 20's are taller your speedo will read lower. Plug your full tire size in to any online calculator like stated above and you will have your answer.
I would have thought that the 305 tire would just be a wide "foot print" and require a wider wheel to mount it on... Nonetheless, thank you for the info.
I don't even recall the last time I looked at my Speedometer.
In Switzerland, we can have until 3.2 million usd in fines when we drive too fast, depending of the revenues. In a 30kph zone, 5kph too much will already disqualifies you from driving for 3 months, 3 years if you have already commited this infraction. And the car can be retired and re-sold by the state to pay your monstrous fine.
I can say to you, we look at our speedos, and we look at them WELL.
But we also have madatory technical inspections. Changing diameter of the wheels on the car would need to present the car again for checking out if they are speed discrepancy. If yes, the wheels wouldn't be approved. It's the reason why I plan to stay on 19" for my aftermarket wheels.
Now THAT is the strongest Traffic Enforcement policy Ive EVER heard of right there Benoit. Insane! I spent some time at both the US Embassy in Bern, and Consulate in Zurich, and must admit you guys have the cleanest City Streets I have ever driven on! In the US we all must go thru some form of Vehicle Inspection as well. Mine is annually, and they could care less about what size tire we choose to mount- as long as it is safe to do so. There are many good looking 19" wheels for sure-I almost went w them but seeing these wheels in 20" is what sold me on them. Do you have some picked out already? BTW- I have absolutely no clue in the world what "Kph" equals anymore - I need to consult a conversion chart to calculate this.
As for inspections... come to Florida. They don't inspect anything. We don't even have emissions testing. Just keep your license plate sticker up to date and you're good to go. I do mine via mail.
I make it a habit to keep the wheel/tire combo OD as close as possible to stock when changing wheel or tire sizes
20" wheels
20s
