Need help with quotation

Anyone remember the Latin translation of “once you got it up, keep it up” from the movie American Flyers?

Please, don’t use a translation engine on the web…It’s not the same quote.

Any help is appreciated.

Cheers,
Puskas

I think it’s:

res firma mitescrene nescit

-Marc
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mitescere
.

I thought it was on the viagra commercial…

I think it’s:

res firma mitescere nescit

-Marc It would more literally translate as “A firm thing does not know how to grow soft.”
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