It depends on traffic and I am not very good with exact times (always too busy looking at all the sights on route ) but I would say between 1 1/4 to an 1 1/2 certainly no more and we have certainly made day trips the other way round i.e Cavelossim to Mapusa/Baga

It can be done in a day but if possible try and book 1 nights accomodation, then you could leave early,book into your hotel,have a full day at the beach,treat yourself to a meal at the Riverview, have a few drinks around Cavelossim, have a good kip, and then spend half day on the beach before heading back up north....you wont be disappointed honest.....Keith

many thanks for those replies will definately go have a look this tiime.

and if looking to stay a night have a look at http://www.palmgroveresidencygoa.com or http://www.saodomingosgoa.com also if you like market towns stop at Margao on the way down and have a wander round the municipal square, warren of a market and have a cold beer in Longhuino's (on one of the corners of the square) and watch the world go by, it's manic but authentic (by that I mean 100% Goan rather than touristy at all) and great fun.