Well, i can only guess without full info about bank or service which you'll use. Typically every 'service' takes some % of your money. If it's usual web-agency it'll probably take a bit less (1 to 3%), than big banks (3 to 20%). Let's guess you are using 'web-agency' to transfer from LTC to BTC and big bank to get your money in USA. You'll lose at least 4% of your money and the maximum (i hope it is max) 23%.

Isn't it obvious? You'll lose some %, maybe 1, maybe 5. It's usual for any currency.

Looks like a good idea