Just fyi, construction at lga causes a lot of delays. Taxi lines are longer than normal (plus you have those useless people trying to turn the taxi line into a line for a club where they seem to slow people down just to keep the line inorganically long), and you can't pick up Ubers and Lyfts from the airport, you have to go to an offsite location.
Also, you may have the people that will further enhance your delay to get out of the airport that insist on collecting every passengers' baggage claim ticket.
Point being: plan on a longer amount of time than you think it will take to get from lga-jfk.