Ianzo - Once again I agree with Carch, the man knows his nuts! ;-)
But once again I would like to add that there is no hard and fast rule to this, and once again, location and species needs to be taken into account.
Example: Shallow water popping, plenty of Coral heads and Bommies around, and you are casting at 20 to 40 kilo GT's.... in a situation like this, you would normally be fishing 100lb plus braid with your drag set at around 12 kilos, because anything else, and you just gonna get smoked.... in fact you'll still get smoked pretty often!!!
But in a situation like this, you are 100% prepared for that strike.... its visual, and you are expecting it.... you aren't popping over deep water where the strike comes outta nowhere, you will 9 times out of 10 see the fish come up before they strike and you'll prepare yourself for it, and for the heavy drag pressure.
Now in a case where you are popping over deeper structure, and with rleatively "lighter" tackle, like your 8000 and 50lb braid, then I would certainly follow the Carhman's advice and fish lighter drags.... for me, set around 5 to 7 kilos probably,using 50lb braid.
And for GT's, you don't really wanna let them run too much, especially if you are over a reef with a drop off nearby.... However, if you have a decent boat skipper, make use of the boat, and get yourself and the boat over and away from the drop off, and this will allow you a much better chance at landing that GT, while using relativelty light tackle.... Look at all the great 20 plus GT's taken by the Blackfin guys, while fishing softplastics/dropshots, on 14lb Braid and relative noodle sticks.... technique, and boat handling play a big factor here, as does using the correct angles on the fish.
Another factor, in some areas, is sharks... GT's make a lot of noise when hooked and fisghting, and can become shark food pretty quick... so if you can get them to the boat quickly, then do it!
While fishing off the beach, a whole other setoff rules comes into play, and one has to way up the whole, LOCK AND SKULLDRAG that fish, which means locking the drag, and putting as much pressure on the fish as possible from the get go.....
Pros:
Can potentially get fish turned and away from any structure immediately.
If you turn them, they can be landed quickly and safely
Sometimes in heavy structure, its your only option
Its a RUSH of note fishing drags that heavy, like a 4 Round Heavy weight bout
Cons:
The potential for tackle failure and pulled hooks, or worse
The risk o the fish fighting harder, and just diving straight into the bricks
Giving yourself a heart attack due to exertion!
The alternative is fishing much lighter drags, and not putting as much acid on the fish from the start as a technique
Pros:
Can allow the fish to swim away from structure and into lesser hectic water, as they don't feel as alarmed under the lighter drags
Can allow one to potentially use lighter tackle to target big fish
Cons:
You can get spooled in a hurry by a bus!!
The potential for a bi fish running you a longer way out, then cutting you off can mean a GT swimming around with a couple hundred metres of braid hanging from his Gob...
Long fights on these fish exhaust them, so the potential to become shark bait is bigger after prolonged fights...
So there are two schools of thought, and each one has its place in certain conditions, certain fish, and on certain tackle... the only way to figure out which works is to get out and test them in as many situations as possible!
There are no hard and fast rules, which is what makes this such a great passion and addiction!
. Abbreviated trip report looming with pics.