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 Post subject: Decreasing tire diameter
PostPosted: February 3, 2023, 3:42 pm 
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Joined: September 2, 2022, 4:13 pm
Posts: 7
I recently purchased a Locost that has 14" wheels with 25" all season tires on it. I want to get some stickier summer tires on it for the spring for autocross and more fun on the road. I can find a few options that will fit on the 14 inch wheels, but the tire diameter is 23".

Other than ground clearance, what else do I need to consider if I'm decreasing tire diameter? Will I be messing with any suspension geometry in a meaningful way?


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PostPosted: February 3, 2023, 4:25 pm 
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You’ll be fine, though the top speed will be decreased, your cruising rpm increased, and your mileage decreased by 23/25. It of course also lowers the car by an inch. You’ll be fine given the above.

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Last edited by KB58 on February 4, 2023, 12:32 pm, edited 1 time in total.

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PostPosted: February 3, 2023, 4:49 pm 
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Joined: July 17, 2008, 9:11 am
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It does not change caster, camber or toe-in. I believe that it may lower the COG by that 1" which may reduce the roll in corners and reduce weight transfer, very slightly. It will also slightly increase acceleration. It will also affect the speedometer reading by that 25/23

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PostPosted: February 3, 2023, 6:13 pm 
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And smaller tires decrease unsprung weight. I lost track of how many "wins" that is.

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PostPosted: February 4, 2023, 1:52 am 
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Joined: March 19, 2011, 10:22 am
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KB58 wrote:
an inch

rx7locost wrote:
that 1"

Geez, that's all wifey talks about, "if only you had one more inch................"

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