OK got my water temp gauge hooked up today (think god for easy outs!

)
and my god she runs cold!
its always ran cold on the std gauge, but i just assumed the gauge/sender was inaccurate...
now its got a new sender and proper gauge and i see the true story...
went out for a hard blast and the MAX temp i saw was 50degrees... normal was 40degrees!
now i knew my engine ran cool (you can leave the car running for HOURS and not have the fans cut in!) but that takes the p*ss...
now 1st assumption is maybe it doesnt havea thermostat fitted, so i'll see if i can get a new one and get the stat housing off to check etc.
now if that doesn't do the trick, does anyone have any ideas?
i assume having it run that cool is not a god idea