SpudFiles

I have 2 identical 3/4" QEVs and am just planing my next launcher, they will be linked in parallel with the hope that although they wont open any faster they will provide the required air faster as there is twice the area supplying the barrel, rather than having a super long barrel to improve performance.

My question is will using Y pieces rather than tees and 90 degree elbows to connect them to a single chamber and from the QEVs to the barrel have a noticeable effect on performance as the air will not be going round so many tight corners? Or is there minimal difference? If it matters the barrel bore is 12mm and I will be using about 300psi, maybe 350 max if feeling confident the QEVs won't blow up. Sorry cant remember if the fitting I have are for 15mm or 22mm copper tube to connect them.

Thanks.

Rule of thumb:
The smallest port in the entire design (air passage) will be the flow limit max.

Yes, the QEV ports are 3/4" BSP and will link them with 22mm copper tube for the chamber to qev and qev to barrel, so once this is taken down to the 12mm barrel bore hopefully airspeed will be increased significantly.

My main worry was do 90 degree turns have a huge effect on air flow? Would it ne better to use Y pieces and 45 degree turns. I imagine if using a T to the barrel air from each side will crash into each other before being forced out the tees central leg. Maybe it wont be of concern considering the restriction of the 12mm barrel.

The air is all ready at the sealing face and the pressure will be equal throughout the storage chambers, connecting tubes and valve body. The 90's and tee will be fine as far as air flow goes.

Great, just what I wanted to hear, hopefully got most of the fittings.already. Thanks