CV spouts and 5/16 drops on 3/16 natural vac

[billyinvt]

I am interested in minimizing backflow on a 3/16 natural vacuum setup. Is anyone using CV spouts on natural vac runs? Do people have good luck using 5/16 drops to lessen backflow issues?

[n8hutch]

If your thinking about putting CVs on new tubing there is no real benefit, I however am running 400 CVs on one year old 3/16 this year, I am using a 3 ft 5/16 drop and new t fittings also.

[Lano75]

I ran all 5/16 drop lines to 3/16 and it worked really well.

[maple flats]

Me too. About 60% of my laterals are in 3/16 but 100% of my drops are 5/16. Some have CV spouts, some have seasonal spouts and some have seasonal spouts.
Last year, on my 3/16 lines which had started new the the year before, I cut the drop just above the 3/16T and used a 3/16 x 5/16 connector and then put a 5/16 drop and tap. I only did that because at the time I could not get 3/16 x 3/16 x5/16 Tees, I now have those tees and it is far better.

[billyinvt]

The tubing is new this year, so I'm not too worried about the CV spouts for this season. I am using the CDL Ts designed for a 5/16 drop and 3/16 lateral. I'm pretty sure Tim Wilmott used a 5/16 drop when he did all his research.