Buoyancy differential between bp/w systems

[GirlonFire]

Ok maybe I’ve had too much wine but I am flummoxed about the weighting change (if any) between my HOG Total Bouancy Control and my new system.
The TBCS weighs in at about 9 lbs and with an 80 cf aluminum tank, I used 3 kilos in lead in 80 degree salt water.
If I use the same wetsuit, fins...in similar water, but switch to a bp/w that weight 6.5 lbs and a 100cf ALU tank, would my bouancy stay about the same?
I know this will be answered on a bouancy check but I am debating weather or not to use a weight belt or attach weight pockets to my harness.

 

[Divectionist]

Can you check the specs of the exact tanks you are using and compare their empty buoyancy? Probably somewhere in the 2-4lbs region? So 'about the same' is likely a fair estimation.

If you are planning to dive this setup permanently, I'd do a precise weight check and throw the loose lead onto cam band trim pockets rather than the weight belt.

 

[Bob DBF]

@Divectionist beat me to it on the tanks.

If I didn't know the answer to your question, i would carry a couple of extra two pounders, cause I hate being underweighted, and when I do my usual weight check at the safety stop, hand any weight I don’t need to my buddy.


Bob

 

[GirlonFire]

Can you check the specs of the exact tanks you are using and compare their empty buoyancy? Probably somewhere in the 2-4lbs region? So 'about the same' is likely a fair estimation.

If you are planning to dive this setup permanently, I'd do a precise weight check and throw the loose lead onto cam band trim pockets rather than the weight belt.

Couldn’t I just thread bare weights onto the cam bands? I do have small HOG weight pockets that would fit onto the tank bands I suppose.

 

[Divectionist]

Couldn’t I just thread bare weights onto the cam bands? I do have small HOG weight pockets that would fit onto the tank bands I suppose.

Do you ever have to adjust your weight or weight distribution? I use 4 pockets on the 2 cam bands and can easily shuffle lead around depending on my configuration. Would not want it fixed because I sometimes need to dive a combo of my own steel tank and the AL80 of a dive boat depending on the number of dives, not to speak of changes to exposure gear or having to balance heavier items pulling on one side out on some dives.

Do you want to take the weight out? My SS bp/w with STA gets too heavy to comfortably handle with lead, so I take the weight out of the pockets when I gear down.