Electric Fan Question

I'm about to order a flex a lite dual electric fans. I was curious if the fan has to be the same length of the radiator? My radiator is 17 inches in Length and the Fan is 15 inches. I don't think it matters but just need to double check.

Should work fine, but try to get the fans as close to the radiator as you can to pull the most air possible.

Thanks Tom got one more question. I got got a nova that I'm only gonna get 500 hp out of. Should I go with single melectric fan or Dual?

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