[Frank pole]

I'm reburbing a couple of machines - I've replaced motors, pumps and gate valves

Would I notice the difference in lift if I replaced spiggot and vac recovery hose in 2 inch instead of the 1.5 that's currently fitted as I really need to be running 50ft of recovery hose minimum!

[john martin]

I'm reburbing a couple of machines - I've replaced motors, pumps and gate valves

Would I notice the difference in lift if I replaced spiggot and vac recovery hose in 2 inch instead of the 1.5 that's currently fitted as I really need to be running 50ft of recovery hose minimum!

If the machine vacs are parallel it may help preserve airflow over a longer length  ...
but lift ( suction) should be the same for both .
Ideally you would replace the tank stack also if there is just one and its thin .

[Frank pole]

I've upgraded stack to 2 inch already just wondering should I carry it on with 2 inch vac hose as I need to replace current 25ft length 1.5 inch

[john martin]

I've upgraded stack to 2 inch already just wondering should I carry it on with 2 inch vac hose as I need to replace current 25ft length 1.5 inch

What is the machine , series or parallel ...   
If you plan on running more hose it be beneficial  ,replace hose connector also .

[Frank pole]

Vacs are in series

[john martin]

Vacs are in series

Dont think it will a big difference  , but it wont cost much to try .

[Kinver_Clean]

Unless you put 6.6s in parallel you won't gain anything.
With 5.7s in series you will be better with 1 1/2" pipe. Series will take time to vent a 2" pipe.
5.7"s in parallel is debatable.

[stuart_clark]

A lot is said about these 6.6 vacs but three 5.7 vacs must produce more cfm and lift, also if one 6.6 fails the machine is rendered just about useless ! I know this as I used to own a Jaguar that kept blowing vac motors, ive never had a problem with any of my Scorpions vac motors, but if you turn off one motor the machine is still more than useable