Position size vs market movement

Hi All,

Just wondering what peoples experience of using larger position sizes when scalping was in Forex (major pairs)?

i.e if you place an 80 standard lot trade, with an 8 pip stop, does anyone find there to be any shift in price due to their trade?

Im not too sure if this even comes into play with this size of trade on such a liquid market.

thanks

Im using an ECN, so if any one has any thoughts on this....