[Ian Gourlay]

I just want machines that suck dirt and water I prefer one that sucked dry and wet saves taking in yet more equipmen

But what puzzles me Extracta has 7.5 motors and the technically minded say its Ok to switch to 5.5 no loss of performance So how come 6.5 gives better perfomance and if it is in design to fan etc what would happen if you sesigned the other two the same way.

As the leading manufacturer is same company what is stopping them.

[Glynn]

The Extracta vac's are 7.2 not 7.5.
I recently replaced one of the 7.2's with a 5.7, so theres a 7.2 & a 5.7 in the same machine.
The vac power is slightly less than when it had 2 7.2's but not so much less than you would notice since they dont really do much in the first place.

[john martin]

  The newer design motor (6.6 and 8.4 )has fan blades that start out thick in the center and get thinner as they go out .
The 5.7 / 7.2 has the same thichness fan blades all the way accross .

 The newer design gives about 40% more airflow ... but it is a two stage and lift is slightly less than a three stage older design ... but not much

 So a twinvac parallel machine (eg alltec ) using 5.7s had  200cfm and 137" lift
 with the twin 6.6 it should have  about 280 cfm and 130" lift .

Comparing the 5.7 to the 7.2 depends on which ones you compare ...
There are 1200w and 1400w versions of both
the 1200w will have generally the same cfm but less lift than the 1400w

the usual 1400w 5.7 has 137" lift and 95 cfm
the 7.2 used to have a little less ... but recently there is one with 144" lift and 100cfm
the 1200w versions will have about 95cfm and 100" lift .

[Shaun_Ashmore]

So which set up offers the best or should I say quickest drying carpets?

Shaun

[john martin]

So which set up offers the best or should I say quickest drying carpets?

Shaun

The twin 6.6 with lots more airflow should have better drying time vs the twin 5.7/7.2

I'd still say triple vac 5.7 has a bit more power .. at least on paper anyway ... but not much and the advantage of twin 6.6 as alltecs machine should demo is u can have heat at the same time on two cords ...  not really possible with the triple vac on two cords.

But Series twin 5.7/7.2   vs  parallel  6.6 would be a whole different argument regarding drying times ....  high suction vs high airflow  ...
could depend on hose length used etc  .

Twin 6.6 parallel with 3000w heat on two cords should be a powerfull convenient to use machine .

[Shaun_Ashmore]

If I had to recommend/design a porti I'd go for a smaller pump with no pump in/out and see if you could get 3 x 6.6 vacs in, it'll be I the resting who'll be the first if at all to offer the 8.4 set up

[john martin]

If I had to recommend/design a porti I'd go for a smaller pump with no pump in/out and see if you could get 3 x 6.6 vacs in, it'll be I the resting who'll be the first if at all to offer the 8.4 set up

Shaun , you could have three 6.6 , big  pump and APO on two cords no problem ,  id say it would all fit in alltecs fiberglass body ...
But id say they made the decision that heat is more important then the ability to run a bit more hose and went with that ...

The 8.4 is 300 US dollars each ... which oftens means it ends up a similar price over here ...  + they are too big for some machine bodies ... and offer not a whole lot more performance ... but im sure it would be noticeable
6.6 has 130" lift and 140CFM
8.4 has  about 150" lift and 145 CFM

[Shaun_Ashmore]

Yes not really much benefit upgrading to the bigger brother, the 3 x 6.6 may be the next porti set up in a few years time it's a pity that a 3 motored older porti would fit them in.

Shaun