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I am buildinglad a race car using wet cells, AGMs. I bought a steel frame several years ago and started buying parts and fitting a few. Currently no parts permanently mounted. Started to make some drawings and found I need to extend frame (looks like it will be about 15"so far). My frame is 3' × 9' without the extension. FramE looks somewhat like a sprint car frame. Will be using 15" tires with 120v DC motor and programmable controller. Many parts still to buy but wondering about using a CVT . Does anybody have some thoughts on CVTS in electrics?
 

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No clue on the CVT but this is a cool project! What sort of racing will you be doing with it? I know SCCA Formula 500 uses a snowmobile based engine and CVT combo maybe that would be useful for you.
 

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Unless the rules require you to use AGM's then they will be a losing strategy!
Today is cheaper and a LOT more effective to use Lithium from a crashed EV

120 volts is too low

A CVT is neither use nor ornament on an electric - unless it is radically UNDERPOWERED - not a "race car"
 

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Production EVs normally use a fixed-ratio (single-speed) transmission. In some cases an EV designer chooses to use a multi-speed transmission, either because it's easiest to use what's already in the car, or to get the motor into a usable speed range for performance over a wide enough range of road speeds. Even if more than one ratio is used, typically a two-speed transmission is enough; the infinite ratios of a CVT are not needed and the inefficiency or complication (depending on design) of a CVT is unwanted.
 

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No clue on the CVT but this is a cool project! What sort of racing will you be doing with it? I know SCCA Formula 500 uses a snowmobile based engine and CVT combo maybe that would be useful for you.
Gee, thanks for consuming what will likely be hours of my free time, as I explore the world of F500! ;) Back in the 1990's I knew a guy who had modified an old F440 for autoslalom competition (using a much larger motorcycle engine and transmission), and I am familiar with the design of his car, but I had no idea that the class had settled into this weird design (suspension with polyurethane pucks for springs and friction washers on rocker arms for damping; rear suspension by de Dion axle), and now I'm into searching for images... :)

Anyway, the CVT in an F500 car or snowmobile includes a centrifugal clutch so the engine speed is kept up to at least some minimum. That's needed for an engine but ineffective and inefficient for an electric motor, so if one of these belt-type CVTs is used, it should be with the clutch removed or locked solidly engaged. The weights and springs which determine the behaviour of the CVT would need to be adjusted to suit the motor characteristics.
 
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